{"title":"Quad Refractors","description":null,"products":[{"product_id":"astro-tech-at86edq-f-7-quad-refractor","title":"Astro-Tech AT86EDQ f\/7 Quad Refractor","description":"\u003cp\u003eAlan Dyer reviewed the AT86EDQ for \u003cem\u003eSky \u0026amp; Telescope\u003c\/em\u003e (July 2025) and called it one of his picks for a desert-island telescope — the one scope he'd take if he could only take one. That's a statement worth unpacking, because this is an 86mm refractor. It's not trying to be the biggest aperture on the field. What it's trying to be is the most versatile small refractor you can buy, and it gets there by doing something most small refractors don't: delivering a flat, corrected field straight from the focuser, with no external flattener required.\u003c\/p\u003e\n\n\u003cp\u003eThe AT86EDQ is a four-element, two-group quadruplet. The front group is an apochromatic triplet with one ED element for color correction. Behind it, a separate internal group containing a second ED element flattens the field. The result is a 44mm corrected image circle — flat, round stars from the center to the corners of a full-frame sensor — with nothing between the focuser and your camera but the included photographic extension tube. No separate field flattener to buy. No spacing to calculate. No wondering whether a generic corrector is well-matched to your scope's optical system. It's done.\u003c\/p\u003e\n\n\u003cp\u003eAt 86mm of aperture, 602mm f\/7, and 18.2 inches retracted, the AT86EDQ is genuinely grab-and-go. It fits on lightweight mounts. It fits in overhead airline compartments. It sets up in minutes and delivers images and views that belie its compact size.\u003c\/p\u003e\n\n\u003ch3\u003eS\u0026amp;T Tested\u003c\/h3\u003e\n\n\u003cp\u003eAlan Dyer's \u003cem\u003eSky \u0026amp; Telescope\u003c\/em\u003e review (July 2025) put the AT86EDQ through rigorous visual and photographic testing. His star test at 200× on Capella showed a well-defined central Airy disc with a clean first diffraction ring — he noted the optics passed the star test by a margin that matched or exceeded any telescope he'd reviewed in recent years. Visually, he found no blue or magenta halo from chromatic aberration — the optics were clean on planets, bright stars, and wide-field deep-sky targets alike. At f\/7 on a Canon R5 (full-frame, 45 megapixels), the internal flattener delivered sharp stars to the corners of the frame with no astigmatism or color flaring. The quad design also proved forgiving of backfocus spacing — within a couple of millimeters either direction, Dyer saw no significant degradation.\u003c\/p\u003e\n\n\u003ch3\u003eThe Quad Optical Design\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ uses a four-lens, two-group optical system. The front group is an apochromatic triplet with one ED element — this handles color correction and primary image formation. Behind it, a separate group containing a second ED element flattens the focal plane. All lens surfaces carry fully multicoated antireflection coatings matched to their specific glass types. The blackened tube interior has five knife-edge baffles, and the focuser includes additional ribs for stray-light suppression.\u003c\/p\u003e\n\n\u003cp\u003eThe two groups are designed as a matched system: the triplet delivers a sharp, color-free image, and the flattener ensures that image lands flat across sensors up to full frame. This is not a triplet with a generic corrector bolted on — the field-flattening group is integral to the optical design, which is why the correction is as clean as it is.\u003c\/p\u003e\n\n\u003ch3\u003eBuilt-In Flat Field — No Flattener Required\u003c\/h3\u003e\n\n\u003cp\u003eThis is the defining advantage of the EDQ design. With a conventional triplet or doublet, the focal plane curves. Stars in the center are sharp, but stars toward the edges elongate as the curved focal surface diverges from the flat sensor. An external field flattener corrects this — but it's a separate purchase, a separate connection, and a separate spacing calculation.\u003c\/p\u003e\n\n\u003cp\u003eThe AT86EDQ eliminates that step. The 44mm corrected image circle covers full-frame sensors (36×24mm) with round stars from center to corners. Alan Dyer's imaging tests on a Canon R5 confirmed excellent field illumination at f\/7 — only gradual, minimal vignetting across the frame. Bolt the camera to the extension tube and shoot.\u003c\/p\u003e\n\n\u003cp\u003eIf you want a faster system, the dedicated ATEDQR 0.8× reducer (sold separately) drops the AT86EDQ from 602mm f\/7 to approximately 482mm f\/5.6 — almost a full stop faster, shorter exposures, and a wider field. The reducer attaches directly to the focuser's M69 threads (the step-down ring is removed first). Dyer's tests showed the reducer preserved the flat field well, with only minor elongation visible at the extreme corners at pixel-peeping magnification.\u003c\/p\u003e\n\n\u003ch3\u003eUnder the Night Sky\u003c\/h3\u003e\n\n\u003cp\u003e86mm of aperture in a well-corrected refractor is more capable than many people expect. The resolution limit is 1.35 arc seconds, and the clean optics deliver high-contrast views that punch above their aperture class.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eMoon:\u003c\/strong\u003e The AT86EDQ shows crisp lunar detail — crater walls, central peaks, and the larger rilles are well-defined. At 86× (7mm eyepiece), you're seeing the full disc with sharp detail across the field. Push to 150× with a 4mm eyepiece and the terminator comes alive — Copernicus shows terraced walls, Plato's floor shows texture, and the Straight Wall is a clean, sharp shadow line.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003ePlanets:\u003c\/strong\u003e At 150× with an Astro-Tech 4mm 82° UWA, Dyer reported Mars showing the North Polar Cap and Syrtis Major clearly during the January 2025 planetary alignment. Jupiter's dark belts showed hints of fine structure, and the Galilean moons were tight points of light. Venus presented a clean white crescent phase with no false color — none of the blue or magenta halo that lesser optics produce. Saturn's Cassini Division is visible at moderate power under steady seeing, and the planet's disc shows subtle banding.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eDouble stars:\u003c\/strong\u003e With a 1.35 arc second Dawes limit, the AT86EDQ splits the classic visual doubles. Epsilon Lyrae (the Double Double) resolves at 150×. Albireo is a striking color-contrast pair at low power. Castor separates cleanly. Dyer noted that Rigel showed its 7th-magnitude companion 9.4 arc seconds from the brilliant primary — a test of contrast as much as resolution — and that Castor split cleanly into its slightly unequal components at 5.6 arc seconds.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eDeep sky:\u003c\/strong\u003e The flat field is a visual advantage as well as a photographic one. Stars are sharp to the edge of the eyepiece field, which makes open clusters and Milky Way sweeping noticeably better than through a conventional refractor. Dyer paired the AT86EDQ with an Astro-Tech 20mm 100° XWA and reported sharp stars to the edges of the field across wide Milky Way vistas. M42 framed beautifully in the 3.3° field with surrounding nebulosity and clusters. The Messier open clusters — M35, M36, M37, M38, the Double Cluster — are spectacular subjects for this scope, with pinpoint stars across the field.\u003c\/p\u003e\n\n\u003ch3\u003eFor the Imager\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ was designed around imaging, and the S\u0026amp;T review confirmed it delivers. At 602mm f\/7 on a Canon R5 (full-frame, 4.4-micron pixels), Dyer found no astigmatism or color flaring in the corners of the frame. The internal flattener was doing its job — flat field, round stars, clean correction.\u003c\/p\u003e\n\n\u003cp\u003eAt this focal length, the field of view on a full-frame sensor is roughly 3.4° × 2.3° — wide enough for the Orion Nebula complex, the Rosette, large open clusters, and widefield Milky Way shots. Add the 0.8× reducer and the field opens to approximately 4.2° × 2.8° at f\/5.6 — nearly a full stop faster with a significantly wider framing.\u003c\/p\u003e\n\n\u003cp\u003eThe scope includes a photographic extension tube that threads into the camera angle adjuster when you're ready to image. The extension tube provides M63, M54, and M48 thread options for connecting cameras and accessories. A set of camera adapter rings (M54 and M48 sizes) is also included, along with 0.5mm and 1mm backfocus shims for fine-tuning sensor spacing. The recommended backfocus is forgiving — Dyer tested ±2mm from the nominal spacing and saw no significant degradation at either f\/7 or f\/5.6.\u003c\/p\u003e\n\n\u003cp\u003eThe camera angle adjuster rotates a full 360° and locks with a large knob — frame your target in landscape, portrait, or any angle between without disassembling the imaging train. The focuser is compatible with electronic focusers like the ZWO EAF for remote, software-controlled focusing.\u003c\/p\u003e\n\n\u003ch3\u003eGrab-and-Go\u003c\/h3\u003e\n\n\u003cp\u003eAt 18.2 inches retracted, 22 inches with the dew shield extended, and approximately 11 pounds with rings and dovetail, the AT86EDQ is the smallest and lightest scope in the EDQ line. It rides comfortably on a ZWO AM3 or AM5, an iOptron GEM28, or any equatorial mount in that class. For visual use, a sturdy alt-az mount or a light equatorial handles it easily.\u003c\/p\u003e\n\n\u003cp\u003eThe scope fits in airline overhead compartments — not all refractors can say that. If you travel to dark sky sites or want a scope that sets up in minutes for a quick session from the backyard, the AT86EDQ's size and weight are a genuine advantage. The included cordura carry case protects it in transit.\u003c\/p\u003e\n\n\u003ch3\u003eThe Focuser\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ's 3.2\" (81mm) rack-and-pinion focuser has 85mm of travel — enough for most eyepiece and camera configurations. The right focus knob has a concentric 10:1 fine-focus knob for precise control. The focuser locks solidly with no image shift when tightened, and Dyer noted it didn't slide out of focus or slip when aimed straight up while carrying a heavy eyepiece and diagonal.\u003c\/p\u003e\n\n\u003cp\u003eThe focuser drawtube terminates in a built-in camera angle adjuster — standard equipment, not an extra-cost accessory. The drawtube has a scale marked in 1mm increments for recording focus positions. Thread options include M63, M54, and M48 via the included adapter set.\u003c\/p\u003e\n\n\u003cp\u003eThe 2\" and 1.25\" accessory holders use non-marring brass compression rings. The existing Astro-Tech 1.25\" dielectric diagonal is a good pairing for visual use — the product page recommends it specifically.\u003c\/p\u003e\n\n\u003ch3\u003eBuild and Mechanical\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ is finished in matte black anodize with red-anodized focuser and camera angle adjuster appointments. Five knife-edge baffles inside the tube control stray light, and the focuser adds additional suppression ribs. The retractable dew shield slides forward 95mm for dew protection and stray-light control.\u003c\/p\u003e\n\n\u003cp\u003eFelt-lined hinged split mounting rings with M6×1 thread mounting holes come standard, along with a Vixen-style dovetail and a handle with a mini Vixen saddle plate. The rings accept a Losmandy-style D-plate dovetail (sold separately) for heavier mounts. A single Synta-standard finderscope shoe is included on the focuser housing.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eAT86EDQ optical tube assembly\u003c\/li\u003e\n  \u003cli\u003eFelt-lined hinged split mounting rings (pair) with M6×1 mounting holes\u003c\/li\u003e\n  \u003cli\u003eCarrying handle with mini Vixen saddle plate\u003c\/li\u003e\n  \u003cli\u003eVixen-style dovetail plate (24cm)\u003c\/li\u003e\n  \u003cli\u003ePhotographic extension tube (M63, M54, M48 threads)\u003c\/li\u003e\n  \u003cli\u003eCamera adapter ring set (M54 and M48 sizes)\u003c\/li\u003e\n  \u003cli\u003eBackfocus shims (0.5mm and 1mm)\u003c\/li\u003e\n  \u003cli\u003e2\" accessory holder with brass compression ring\u003c\/li\u003e\n  \u003cli\u003e1.25\" accessory adapter with brass compression ring\u003c\/li\u003e\n  \u003cli\u003eRetractable dew shield\u003c\/li\u003e\n  \u003cli\u003eFinderscope mounting shoe (Synta-standard)\u003c\/li\u003e\n  \u003cli\u003eSlip-on metal dust cap\u003c\/li\u003e\n  \u003cli\u003eCordura nylon carry case\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCommunity Says\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003e\"Build quality is excellent. Baffling of both the OTA and focuser assembly is well executed. Quite impressive actually. The focuser is beefy and...\"\u003c\/strong\u003e\u003cbr\u003e\n— \u003ca href=\"https:\/\/www.cloudynights.com\/forums\/topic\/958297-at86edq-f7-quad\/?do=findComment\u0026amp;comment=14032147\"\u003eCloudy Nights AT86EDQ discussion\u003c\/a\u003e. This owner logged over 80 hours behind the AT86EDQ for visual observing and found it impressive on solar, Venus, and planets.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e\"On open clusters, it delivered pinpoint stars edge to edge.\"\u003c\/strong\u003e\u003cbr\u003e\n— \u003ca href=\"https:\/\/www.cloudynights.com\/forums\/topic\/973250-astro-tech-at86edq-quad-f7-owners-thread\/?do=findComment\u0026amp;comment=14282175\"\u003eCloudy Nights AT86EDQ Owners Thread\u003c\/a\u003e. This owner used the scope visually on Scorpius and Sagittarius summer targets and also noted: \"I cannot see that it gives up anything to my FCD-100 or FPL-53 triplets.\"\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e\"I have used this scope quite a bit and have found it to be excellent. The build quality is outstanding and the optics are quite good. With and without the reducer, the stars are sharp all the way to the edge of an aps-c sized sensor.\"\u003c\/strong\u003e\u003cbr\u003e\n— \u003ca href=\"https:\/\/www.cloudynights.com\/forums\/topic\/958297-at86edq-f7-quad\/?do=findComment\u0026amp;comment=14032103\"\u003eCloudy Nights AT86EDQ discussion\u003c\/a\u003e. This owner tested the AT86EDQ both visually and photographically.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e\"Sharp and clean and I could see faint bandings on the disc of Saturn, something I'm not sure I've noticed on the 14-inch dob.\"\u003c\/strong\u003e\u003cbr\u003e\n— \u003ca href=\"https:\/\/www.cloudynights.com\/forums\/topic\/973250-astro-tech-at86edq-quad-f7-owners-thread\/?do=findComment\u0026amp;comment=14289986\"\u003eCloudy Nights AT86EDQ Owners Thread\u003c\/a\u003e. This owner came to the AT86EDQ from a 14\" Dobsonian and was struck by the refractor's planetary contrast.\u003c\/p\u003e\n\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuadruplet optical system with two ED elements.\u003c\/strong\u003e Four-lens, two-group design: an apochromatic ED triplet objective plus a separate internal ED field-flattening group. Color correction and flat field are built into the optical system. S\u0026amp;T star test: at least ¼-wave, with no false color on planets or bright stars.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBuilt-in flat field to full frame — no external flattener required.\u003c\/strong\u003e The internal ED field-flattening group delivers a 44mm corrected image circle. Round stars from center to corners on full-frame sensors, confirmed by S\u0026amp;T testing on a Canon R5.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e86mm aperture at 602mm f\/7 — grab-and-go size.\u003c\/strong\u003e 18.2\" retracted, ~11 lbs with rings. Fits on lightweight mounts and in airline overhead compartments. Sets up in minutes.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eS\u0026amp;T reviewed (July 2025).\u003c\/strong\u003e Alan Dyer: \"one of my picks for a desert-island telescope.\" Passed the star test by a margin matching or exceeding any scope recently reviewed.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eForgiving backfocus spacing.\u003c\/strong\u003e S\u0026amp;T testing showed ±2mm from nominal had no significant effect on image quality at either f\/7 or f\/5.6. Less fiddling on setup night.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompatible with the ATEDQR 0.8× reducer.\u003c\/strong\u003e Add the dedicated reducer (sold separately) to drop from 602mm f\/7 to ~482mm f\/5.6 — almost a full stop faster, wider field, shorter exposures.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e3.2\" dual-speed rack-and-pinion focuser with 10:1 fine focus.\u003c\/strong\u003e 85mm of travel, solid lock with no image shift, mm-scale drawtube markings. EAF compatible.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBuilt-in camera angle adjuster.\u003c\/strong\u003e 360° rotation standard — frame targets in any orientation without disassembling the imaging train.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePhotographic extension tube and adapter set included.\u003c\/strong\u003e M63, M54, and M48 thread options. Camera adapter rings and backfocus shims included in the box — not sold separately.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFive knife-edge baffles plus focuser suppression ribs.\u003c\/strong\u003e Thorough internal stray-light control for high contrast on planets and deep sky.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eObserving Tip\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ at 602mm f\/7 with a wide-field eyepiece is one of the best open-cluster scopes you can own. Drop in a 20mm 100° eyepiece (30×, 3.3° true field) and sweep through the Milky Way from Cygnus to Sagittarius. The flat field means every star in that 3.3° field is a point — not a smear — from center to edge. Open clusters pop against the background in a way that scopes with curved fields don't quite match. For M35, M36, M37, M38, and the Double Cluster, this is hard to beat at any price.\u003c\/p\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003eDo I need a separate field flattener?\u003c\/strong\u003e\u003cbr\u003e\nNo. The AT86EDQ has a built-in ED field-flattening group that delivers a flat, corrected field across full-frame sensors. No external flattener needed — this is one of the primary advantages of the quad design. The only optional optic is the ATEDQR 0.8× reducer if you want a faster focal ratio and wider field.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003cbr\u003e\nAt ~11 lbs with rings and dovetail, the AT86EDQ is light enough for mounts like the ZWO AM3 or AM5, iOptron GEM28, or a Sky-Watcher HEQ5. For visual use, a sturdy alt-az mount handles it well. This is a genuinely portable scope — it doesn't demand a heavy mount.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eHow does this compare to the AT90EDX or AT90CFT?\u003c\/strong\u003e\u003cbr\u003e\nDifferent designs for different priorities. The AT90EDX\/CFT is a 90mm f\/6 FCD-100 triplet with a guaranteed .95 Strehl ratio — premium optics with the highest-grade glass. But it needs a separate field flattener for imaging. The AT86EDQ is a quad with a built-in flat field — you give up 4mm of aperture and the Strehl guarantee, but you gain a simpler imaging train and no external flattener. Both are excellent visual scopes. CN users who own both report comparable visual performance on planets and double stars.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCan I use this just for visual observing?\u003c\/strong\u003e\u003cbr\u003e\nAbsolutely. Multiple CN owners use the AT86EDQ exclusively for visual and report excellent results on planets, double stars, open clusters, and deep sky. The flat field is a visual advantage too — stars are sharp to the edge of wide-field eyepieces, which makes sweeping and cluster observing noticeably better.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eHow does the AT86EDQ compare to the AT106EDQ and AT126EDQ?\u003c\/strong\u003e\u003cbr\u003e\nSame optical design in three aperture sizes, all f\/7. The AT86EDQ (86mm, 602mm, ~11 lbs) is the grab-and-go — lightest, shortest, airline-capable. The AT106EDQ (106mm, 742mm, ~14 lbs) is the mid-size option with 52% more light grasp. The AT126EDQ (126mm, 882mm, ~17.7 lbs) is the big one — most aperture and resolution, heaviest mount requirements. All share the ATEDQR 0.8× reducer and the built-in flat field.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat did S\u0026amp;T note as drawbacks?\u003c\/strong\u003e\u003cbr\u003e\nAlan Dyer noted three things: the focuser tube itself doesn't rotate (the camera angle adjuster handles rotation instead, but lacks index markings for repeatable positioning), and threading 48mm filters into the adapter ring was difficult. These are minor mechanical issues — the optics and optical performance drew no complaints.\u003c\/p\u003e\n\n\u003ch3\u003eAccessories\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eATEDQR 0.8× Reducer (sold separately):\u003c\/strong\u003e Drops the AT86EDQ from 602mm f\/7 to ~482mm f\/5.6. Almost a full stop faster, wider field, full-frame coverage. Threads directly to the focuser's M69 threads (remove the step-down ring first).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eT-ring for your camera mount:\u003c\/strong\u003e Required for connecting DSLR and mirrorless cameras. Dedicated CMOS\/CCD astronomy cameras typically have 48mm T-threads built in and connect directly via the included adapter rings.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAstro-Tech 1.25\" Dielectric Diagonal (AT1D):\u003c\/strong\u003e Recommended on the product page for visual use. High-reflectivity dielectric coating.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFinder or guide scope:\u003c\/strong\u003e The AT86EDQ ships with one finderscope shoe. Add a red-dot finder for visual use or a guide scope for autoguided imaging. Consider a second shoe if you want both.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eZWO EAF electronic focuser:\u003c\/strong\u003e Compatible with the AT86EDQ's focuser for motorized, software-controlled focusing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFinal Thoughts\u003c\/h3\u003e\n\n\u003cp\u003eThe AT86EDQ is the smallest flat-field quad in the Astro-Tech line — 86mm of aperture at 602mm f\/7 with a built-in ED field flattener that delivers round stars across full-frame sensors without an external corrector. Alan Dyer put it through a full S\u0026amp;T review and found optics that matched or exceeded anything he'd tested recently, with a star test that was textbook-clean and imaging performance that held up on a 45-megapixel full-frame camera. The CN community calls it excellent for visual, excellent for imaging, and built like it means business. At 18.2 inches retracted and roughly 11 pounds, it goes where you go — backyard, dark sky site, or the overhead bin of a 737. If you want one refractor that does visual and imaging without compromise and without needing a separate flattener, and you want to actually carry it out to the backyard on a weeknight, this is the scope that earns that job.\u003c\/p\u003e\n\u003ch2\u003eTech Details:\u003c\/h2\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eModel\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eAstro-Tech AT86EDQ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOptical Design\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eQuadruplet (4 lens \/ 2 group) with built-in ED field flattener\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAperture\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e86mm (3.38\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Length\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e602mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003ef\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eED Elements\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2 (one in triplet objective, one in field flattener group)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCorrected Image Circle\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e44mm (full frame and smaller)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCoatings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFully multicoated on all air-to-glass surfaces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eInternal Baffling\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e5 knife-edge baffles plus focuser suppression ribs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eResolution (Dawes Limit)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1.35 arc seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eVisual Limiting Magnitude\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e12.37\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHighest Useful Magnification\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e169×\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e3.2\" (81mm) dual-speed rack-and-pinion, 10:1 fine focus ratio\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Travel\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e85mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Threads\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eM69 (camera rotator), M63, M54, M48 (via extension tube and adapters)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCamera Angle Adjuster\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eBuilt-in, 360° rotation with locking knob\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAccessory Holders\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2\" and 1.25\" with non-marring brass compression rings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDew Shield\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eRetractable (self-storing), extends 95mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (retracted)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e18.2\" (46cm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (extended)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e22\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWeight (with rings, dovetail, handle)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e11.2 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHeaviest Single Component\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e9.5 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eTube Finish\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eMatte black anodize with red-anodized focuser and appointments\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eMounting Rings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFelt-lined hinged split rings with M6×1 mounting holes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDovetail\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eVixen-style, 24cm (Losmandy D-plate compatible via mounting holes)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCompatible Reducer\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eATEDQR 0.8× (602mm f\/7 → ~482mm f\/5.6)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCarry Case\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eCordura nylon\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1 year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"Astro-Tech","offers":[{"title":"Default Title","offer_id":41598307500105,"sku":"AT86EDQ","price":1399.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0573\/7974\/9961\/files\/AT86EDQ_1-9488.jpg?v=1731697669"},{"product_id":"astro-tech-at106edq-f-7-quad-refractor","title":"Astro-Tech AT106EDQ f\/7 Quad Refractor","description":"\u003cp\u003eYou buy a refractor for imaging, and the first thing you learn is that you need a field flattener. Then you learn that the flattener has to match your scope's focal length and field curvature, and the spacing from flattener to sensor has to be precise, and the whole assembly adds weight and length and one more potential source of tilt. It works — but it's a workaround for a problem that the optical system itself created.\u003c\/p\u003e\n\u003cp\u003eThe AT106EDQ builds the correction into the optical system. Four elements in two groups: an apochromatic ED triplet objective handles color correction and image formation, and a separate internal ED field-flattening group flattens the field. The result is a 44mm corrected image circle — flat, sharp, round stars from center to the corners of a full-frame sensor — with nothing between the focuser and your camera but air. No external flattener. No spacing guesswork. No adapter stack.\u003c\/p\u003e\n\u003cp\u003eAt 106mm of aperture and 742mm f\/7, the AT106EDQ sits in the middle of the EDQ line — more aperture and reach than the AT86EDQ, more portable and mount-friendly than the AT126EDQ. It's the size where you start seeing real deep-sky structure in your images and at the eyepiece, without needing a pier-mounted equatorial to carry it.\u003c\/p\u003e\n\u003ch3\u003eThe Quad Optical Design\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ uses a four-lens, two-group optical system. The front group is an apochromatic triplet with one ED element — this controls chromatic aberration and forms the primary image. Behind it, a separate group containing a second ED element flattens the focal plane. The two groups are designed as a matched system: the triplet delivers a sharp, color-corrected image, and the flattener ensures that image lands flat across sensors up to 36×24mm.\u003c\/p\u003e\n\u003cp\u003eAll lens surfaces carry fully multicoated antireflection coatings matched to their specific glass types. The result is high light transmission, excellent contrast, and images free of the faint color halos that show up around bright stars in less-corrected optics. At f\/7, chromatic aberration is tightly controlled — bright stars are clean, the lunar limb is crisp, and planetary discs show color fidelity that does justice to what's actually there.\u003c\/p\u003e\n\u003ch3\u003eBuilt-In Flat Field — No Flattener Required\u003c\/h3\u003e\n\u003cp\u003eThis is the core advantage of the EDQ design. With a standard triplet or doublet refractor, the focal plane curves. Stars are sharp in the center but stretch toward the edges as the curved focal surface diverges from the flat chip. You add a field flattener to fix it — an extra piece of glass, an extra connection, extra spacing to get right.\u003c\/p\u003e\n\u003cp\u003eThe AT106EDQ eliminates that step. The internal ED field-flattening group is optically matched to the objective because it was designed as part of the same system — not added after the fact by a third-party manufacturer. The 44mm corrected image circle covers full-frame sensors with round stars from center to corners. Bolt the camera to the focuser and shoot.\u003c\/p\u003e\n\u003cp\u003eIf you want a faster system, the dedicated ATEDQR 0.8× reducer drops the AT106EDQ from 742mm f\/7 to approximately 594mm f\/5.6 — a 56% increase in light per pixel, shorter exposures, and a wider field. Because the field is already flat at the native focal length, the reducer's job is straightforward focal reduction rather than trying to correct and reduce simultaneously.\u003c\/p\u003e\n\u003ch3\u003eUnder the Night Sky\u003c\/h3\u003e\n\u003cp\u003e106mm of aperture in a well-corrected refractor puts you in a productive range for both visual observing and imaging. The resolution limit is 1.3 arc seconds — enough to split moderately tight doubles and resolve fine structure on the Moon and planets.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMoon:\u003c\/strong\u003e The AT106EDQ shows the Moon in impressive detail. Plato's craterlets begin to emerge under steady seeing. The Straight Wall is a clean, sharp feature at any power. Copernicus shows terraced walls and the central peak cluster. The Alpine Valley is resolved as a distinct channel, and the smaller rilles across the maria show up under good conditions at 150× and above.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlanets:\u003c\/strong\u003e Jupiter shows the two main equatorial belts with internal detail — festoons, barges, and the Great Red Spot with visible structure on the best nights. Shadow transits are clean black dots. Saturn's Cassini Division is a crisp, dark gap at moderate power, and the planet's belted disc shows subtle banding. Mars at opposition shows dark surface markings and the polar cap with the clean color rendition that a well-corrected refractor delivers.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDouble stars:\u003c\/strong\u003e With a 1.3 arc second Dawes limit, the AT106EDQ splits the classic doubles cleanly. Epsilon Lyrae (the Double Double) separates at 150×. Albireo is a dramatic color-contrast pair at low power. Castor splits easily. Tighter pairs like Zeta Herculis (1.4\") are within reach under steady seeing. The clean Airy discs and high contrast of a good refractor make doubles one of its best visual subjects.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeep sky:\u003c\/strong\u003e 106mm gathers enough light to show real structure in the brighter Messier objects. M13 shows individual stars resolving across its face at 100× and above. M42 delivers the four Trapezium stars crisply with nebulosity streaming outward. M57 (the Ring Nebula) shows its annular shape clearly. Open clusters like the Double Cluster, M35, and M37 are spectacular — and the flat field means stars at the edge of the eyepiece are as sharp as those in the center. That flat field is a visual advantage too, not just an imaging one.\u003c\/p\u003e\n\u003ch3\u003eFor the Imager\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ was designed with imaging in mind. At 742mm f\/7 with a flat field to full frame, it frames deep-sky targets at a versatile image scale — enough focal length that mid-size targets like the Crab Nebula, the Leo Triplet, and the Veil Nebula East or West arcs fill an APS-C frame with detail, and enough field of view on full frame that larger targets like the Rosette or the North America Nebula fit comfortably.\u003c\/p\u003e\n\u003cp\u003eAdd the ATEDQR 0.8× reducer and the system drops to approximately 594mm f\/5.6. The wider field frames bigger targets — M31 with both companions, the Heart and Soul complex, wide Milky Way fields — and the faster focal ratio cuts exposure times. The 56% increase in light per pixel means shorter subs or deeper signal in the same integration time.\u003c\/p\u003e\n\u003cp\u003eThe camera angle adjuster is standard equipment — rotate the camera to frame your target in landscape, portrait, or any angle in between. The focuser drawtube has a millimeter scale for recording focus positions, and the focus lock prevents shift during long exposures. The focuser is compatible with electronic focusers like the ZWO EAF for remote focusing.\u003c\/p\u003e\n\u003ch3\u003eThe Mid-Size Sweet Spot\u003c\/h3\u003e\n\u003cp\u003eThe EDQ line spans three apertures: 86mm, 106mm, and 126mm. The AT86EDQ is the grab-and-go — light, compact, airline-friendly. The AT126EDQ is the heavyweight — maximum aperture and resolution, but 17.67 pounds on the mount. The AT106EDQ sits between them, and that middle position is its strength.\u003c\/p\u003e\n\u003cp\u003eAt 14.33 pounds with rings and dovetail, the AT106EDQ rides comfortably on a ZWO AM5, an iOptron GEM28, or an HEQ5-class equatorial mount — the mounts most amateur imagers actually own. It doesn't demand a pier-mounted EQ6 or a permanent setup. At 23.6 inches retracted, it's manageable to carry out to the backyard in one trip. And 106mm of aperture gathers 52% more light than the 86mm version — enough to make a visible difference in exposure times and the faintness of structure you can reach.\u003c\/p\u003e\n\u003cp\u003eIf you're looking for a refractor that images flat out of the box, works on a mid-weight mount, and gives you enough aperture to do serious work without the weight and cost of the 126mm, this is the one that threads that needle.\u003c\/p\u003e\n\u003ch3\u003eThe Focuser\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ's 3.2\" rack-and-pinion focuser is built for imaging loads. The right focus knob has a concentric 10:1 fine-focus knob for precise control during critical focusing. The focuser drawtube terminates in a built-in camera angle adjuster that rotates a full 360° and locks at any position — standard equipment, not an extra-cost accessory.\u003c\/p\u003e\n\u003cp\u003eThread options include M63, M54, and M48 — connecting reducers, filter wheels, and cameras without stacking adapters. The 2\" accessory holder uses non-marring brass compression rings, and a 1.25\" adapter is included for smaller eyepieces.\u003c\/p\u003e\n\u003cp\u003eThe drawtube has a millimeter scale for recording focus positions. A lock knob under the focuser secures focus during imaging. The focuser is compatible with electronic focusers like the ZWO EAF for motorized, software-controlled focusing.\u003c\/p\u003e\n\u003ch3\u003eBuild and Mechanical\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ is finished in matte black anodize with black-anodized focuser and red accent appointments. The retractable dew shield slides forward from 23.6\" retracted to 29.3\" extended — functional for dew prevention and stray light control, and self-storing so there's nothing extra to track.\u003c\/p\u003e\n\u003cp\u003eThe scope ships with felt-lined hinged split mounting rings with M6×1 thread mounting holes in the top and bottom of each ring. A Vixen-style dovetail and a handle with a mini Vixen saddle plate are included. For heavier equatorial mounts, the rings accept a Losmandy-style D-plate dovetail (sold separately). A dovetail shoe on the upper focuser accepts optional finders or guide scopes.\u003c\/p\u003e\n\u003cp\u003eAt 14.33 pounds with rings, dovetail, and handle (heaviest single component 12.6 pounds), the AT106EDQ is manageable for one-person setup on mid-weight mounts.\u003c\/p\u003e\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eAT106EDQ optical tube assembly\u003c\/li\u003e\n\u003cli\u003eFelt-lined hinged split mounting rings (pair) with M6×1 mounting holes\u003c\/li\u003e\n\u003cli\u003eCarrying handle with mini Vixen saddle plate\u003c\/li\u003e\n\u003cli\u003eVixen-style dovetail plate\u003c\/li\u003e\n\u003cli\u003e2\" accessory holder with brass compression ring\u003c\/li\u003e\n\u003cli\u003e1.25\" accessory adapter with brass compression ring\u003c\/li\u003e\n\u003cli\u003eRetractable dew shield\u003c\/li\u003e\n\u003cli\u003eFinderscope mounting shoe\u003c\/li\u003e\n\u003cli\u003eSlip-on metal dust cap\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuadruplet optical system with two ED elements.\u003c\/strong\u003e Four-lens, two-group design: an apochromatic ED triplet objective plus a separate internal ED field-flattening group. Color correction and flat field are built into the optical system — not bolted on as an afterthought.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in flat field to full frame — no external flattener required.\u003c\/strong\u003e The internal ED field-flattening group delivers a 44mm corrected image circle. Stars are round from center to corners across full-frame (36×24mm) sensors. No separate flattener to buy, no spacing to calculate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e106mm aperture at 742mm f\/7.\u003c\/strong\u003e The mid-size EDQ — enough aperture for serious deep-sky imaging and visual observing, at a weight and size that works on mid-range equatorial mounts.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully multicoated optics.\u003c\/strong\u003e All air-to-glass surfaces carry antireflection multicoatings matched to their glass types. High light transmission, excellent contrast, and clean images free of color fringing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible with the ATEDQR 0.8× reducer.\u003c\/strong\u003e Add the dedicated reducer (sold separately) to drop from 742mm f\/7 to ~594mm f\/5.6 — 56% more light per pixel, shorter exposures, wider field — while preserving the flat field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3.2\" dual-speed rack-and-pinion focuser with 10:1 fine focus.\u003c\/strong\u003e Precise, imaging-capable, with ribbed knobs operable in gloves. Focus lock, mm-scale drawtube markings, and EAF compatibility.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in camera angle adjuster.\u003c\/strong\u003e 360° rotation standard — not an extra-cost accessory. Frame targets in any orientation without disassembling the imaging train.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM63, M54, and M48 focuser threads.\u003c\/strong\u003e Multiple thread options for connecting reducers, filter wheels, and cameras without adapter stacks.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNon-marring brass compression rings.\u003c\/strong\u003e Both 2\" and 1.25\" accessory holders grip without scratching your eyepiece or accessory barrels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetractable dew shield.\u003c\/strong\u003e Self-storing — slides forward for use, retracts for transport. Controls dew and stray light.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eObserving Tip\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ's flat field makes it a natural for visual sweeping of star-rich Milky Way fields and open clusters. Drop in a wide-field 2\" eyepiece — a 30mm or 35mm — and sweep through Cygnus, Sagittarius, or the Perseus arm. Stars are sharp to the edge of the field, not just in the center. That's the visual payoff of the built-in flattener: you see stars as points everywhere in the field of view, which makes rich star fields and open clusters noticeably more satisfying than through a conventional refractor where the edge stars stretch.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eDo I need a separate field flattener with this scope?\u003c\/strong\u003e\u003cbr\u003eNo. The AT106EDQ has a built-in ED field-flattening group that delivers a flat, corrected field across full-frame sensors. No external flattener needed. The only optional optic is the ATEDQR 0.8× reducer if you want a faster focal ratio and wider field.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does this compare to the AT86EDQ and AT126EDQ?\u003c\/strong\u003e\u003cbr\u003eSame optical design in three apertures. The AT86EDQ (86mm, 602mm f\/7, ~11 lbs) is the grab-and-go — lightest, shortest, airline-capable. The AT126EDQ (126mm, 882mm f\/7, ~17.7 lbs) has the most aperture and resolution but needs a heavier mount. The AT106EDQ (106mm, 742mm f\/7, ~14.3 lbs) is the middle ground — 52% more light than the 86, manageable on mounts like the AM5 or HEQ5, and $700 less than the 126. If you want one EDQ that balances aperture, portability, and mount compatibility, this is it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003cbr\u003eAt 14.33 lbs with rings and dovetail, the AT106EDQ works well on a ZWO AM5, iOptron GEM28, or HEQ5-class equatorial for imaging. For visual use, a solid alt-az mount or lighter equatorial will handle it. This is manageable for backyard one-person setup — no permanent pier required.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use this visually, or is it imaging-only?\u003c\/strong\u003e\u003cbr\u003eThe AT106EDQ works beautifully for visual observing. 106mm of well-corrected aperture delivers excellent planetary, double star, and deep-sky views. The flat field is a visual advantage too — stars are sharp to the edge of wide-field eyepieces, which makes open clusters and Milky Way sweeping particularly rewarding.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this come with a finder?\u003c\/strong\u003e\u003cbr\u003eA finderscope mounting shoe is included on the focuser housing, but you'll need to add your own finder or guide scope. This lets you choose the setup that matches your use — a red-dot finder for visual, or a guide scope for autoguided imaging.\u003c\/p\u003e\n\u003ch3\u003eAccessories\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eATEDQR 0.8× Reducer:\u003c\/strong\u003e Drops the AT106EDQ from 742mm f\/7 to ~594mm f\/5.6. Faster exposures, wider field, full-frame coverage. Designed specifically for the EDQ series.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eT-ring for your camera mount:\u003c\/strong\u003e Required for connecting DSLR and mirrorless cameras. Dedicated CMOS\/CCD astronomy cameras typically have 48mm T-threads built in and connect directly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinder or guide scope:\u003c\/strong\u003e The AT106EDQ ships with a finderscope shoe but no finder. Add a red-dot finder for visual use or a guide scope for autoguided imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eZWO EAF electronic focuser:\u003c\/strong\u003e Compatible with the AT106EDQ's focuser for motorized, software-controlled focusing during remote imaging sessions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eATDUP13 Losmandy D-Plate ($79.95):\u003c\/strong\u003e Upgrade from the included Vixen dovetail for heavier equatorial mounts with Losmandy saddles.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFinal Thoughts\u003c\/h3\u003e\n\u003cp\u003eThe AT106EDQ is the mid-size quad in the Astro-Tech EDQ line — 106mm of aperture at 742mm f\/7 with a built-in ED field flattener that delivers round stars across full-frame sensors without an external corrector. For imagers, it means a shorter, simpler optical train and one less thing to get wrong on setup night. For visual observers, it means 106mm of clean refractor aperture with a flat field that makes wide-field sweeping and open clusters look the way they should. At 14.33 pounds, it rides comfortably on the mounts most amateur imagers already own. Add the 0.8× reducer and you have two focal lengths in one scope — f\/7 for image scale, f\/5.6 for speed. If you want a refractor that images flat out of the box, doesn't demand a heavy mount, and sits at a price point between the compact AT86EDQ and the full-aperture AT126EDQ, the AT106EDQ is the one that balances all three.\u003c\/p\u003e\n\u003ch2\u003eTech Details:\u003c\/h2\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eModel\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eAstro-Tech AT106EDQ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOptical Design\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eQuadruplet (4 lens \/ 2 group) with built-in ED field flattener\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAperture\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e106mm (4.17\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Length\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e742mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003ef\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eED Elements\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2 (one in triplet objective, one in field flattener group)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCorrected Image Circle\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e44mm (full frame and smaller)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCoatings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFully multicoated on all air-to-glass surfaces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eResolution (Dawes Limit)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1.3 arc seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eVisual Limiting Magnitude\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e12.83\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHighest Useful Magnification\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e169×\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e3.2\" dual-speed rack-and-pinion, 10:1 fine focus ratio\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Threads\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eM63, M54, M48\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCamera Angle Adjuster\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eBuilt-in, 360° rotation with locking knob\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAccessory Holders\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2\" and 1.25\" with non-marring brass compression rings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDew Shield\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eRetractable (self-storing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (retracted)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e23.6\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (extended)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e29.3\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWeight (with rings, dovetail, handle)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e14.33 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHeaviest Single Component\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e12.6 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eTube Finish\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eMatte black anodize with black and red appointments\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eMounting Rings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFelt-lined hinged split rings with M6×1 mounting holes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDovetail\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eVixen-style (Losmandy D-plate compatible via mounting holes)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCompatible Reducer\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eATEDQR 0.8× (742mm f\/7 → ~594mm f\/5.6)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1 year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"Astro-Tech","offers":[{"title":"Default Title","offer_id":41598429265993,"sku":"AT106EDQ","price":1999.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0573\/7974\/9961\/files\/106B.png?v=1756397415"},{"product_id":"astro-tech-at126edq-f-7-quad-refractor","title":"Astro-Tech AT126EDQ f\/7 Quad Refractor","description":"\u003cp\u003eMost refractors need a separate field flattener to image properly. You buy the scope, then you buy the flattener, then you figure out the spacing, then you hope the correction matches the optical system well enough to deliver round stars in the corners. It works — we sell a lot of flatteners — but it's an extra piece of glass, an extra connection, and one more thing to get right.\u003c\/p\u003e\n\u003cp\u003eThe AT126EDQ takes a different approach. The field correction is built in. The four-element, two-group optical system uses an ED element in the apochromatic triplet objective and a second ED element in a separate internal field-flattening group. The result is a flat, corrected field straight from the focuser — no external flattener required. Stars are round from center to edge across sensors up to full frame, with a 44mm corrected image circle. You bolt the camera to the focuser and shoot.\u003c\/p\u003e\n\u003cp\u003eAt 126mm of aperture and 882mm f\/7, this is the largest scope in the EDQ line. More aperture means more light, more resolution, and more reach into faint structure. The AT86EDQ and AT106EDQ are excellent instruments for their size, but 126mm puts you into a different class of target — fainter galaxies, tighter nebula detail, smaller planetary nebulae that need the extra resolution to show their structure. And you get all of that with the flat field that defines the EDQ design.\u003c\/p\u003e\n\u003ch3\u003eThe Quad Optical Design\u003c\/h3\u003e\n\u003cp\u003eThe AT126EDQ is a four-lens, two-group system. The front group is an apochromatic triplet with one ED element — this handles the heavy lifting of color correction and primary image formation. Behind it, a separate group containing a second ED element flattens the field. The two groups work together as a system: the triplet delivers a sharp, color-free image, and the flattener ensures that image lands flat across a sensor up to 36×24mm.\u003c\/p\u003e\n\u003cp\u003eAll lens surfaces are fully multicoated with antireflection coatings matched to their specific glass types. The result is high light transmission, excellent contrast, and clean images free of the faint color halos that plague lesser optical designs. At f\/7, the AT126EDQ controls chromatic aberration exceptionally well — bright stars show no color fringing, and high-contrast targets like the lunar limb and planetary discs are clean.\u003c\/p\u003e\n\u003ch3\u003eBuilt-In Flat Field — No Flattener Required\u003c\/h3\u003e\n\u003cp\u003eThis is the defining advantage of the EDQ design. With a conventional triplet or doublet refractor, the focal plane curves. Stars in the center are sharp, but stars at the edges elongate as the curved focal surface diverges from the flat sensor. An external field flattener corrects this — but you have to buy it separately, get the back focus spacing right, and hope the correction is well-matched to the scope.\u003c\/p\u003e\n\u003cp\u003eThe AT126EDQ eliminates all of that. The internal ED field-flattening group is optically matched to the objective lens because it was designed as part of the same system. The 44mm corrected image circle covers full-frame sensors with flat, round stars from center to corners. No external flattener to buy, no spacing to calculate, no wondering whether a generic flattener will work with your specific scope. It's done.\u003c\/p\u003e\n\u003cp\u003eIf you want to go faster, we sell a dedicated 0.8× reducer that drops the AT126EDQ from 882mm f\/7 to 706mm f\/5.6 — a 56% increase in light per pixel, shorter exposures, and a wider field. Because the field is already flat, the reducer's only job is focal reduction. It preserves the flat field the scope was designed to deliver.\u003c\/p\u003e\n\u003ch3\u003eUnder the Night Sky\u003c\/h3\u003e\n\u003cp\u003e126mm of aperture in a refractor is serious glass. The resolution limit is 1.1 arc seconds — enough to split tight doubles and resolve fine planetary detail that smaller scopes can't touch.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eMoon:\u003c\/strong\u003e At 126mm, the Moon is deeply detailed. The Alpine Valley rille is visible under good seeing. Craterlets on the floor of Plato resolve as individual pits rather than a general roughness. The terraced walls of Copernicus show their full complexity, and the Straight Wall casts a razor-sharp shadow at the right phase. At 200× to 248×, you're seeing structure that disappears in an 80mm or 90mm scope.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePlanets:\u003c\/strong\u003e Jupiter shows the major equatorial belts with internal festoon structure, the Great Red Spot with visible texture, and shadow transits as sharp black dots. Saturn's Cassini Division is a clean, dark line at moderate power, and the crepe ring is visible against the planet's disc with careful observation. Mars at opposition shows dark surface markings — Syrtis Major, the polar cap, and limb clouds — with the color fidelity that only a well-corrected refractor delivers.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDouble stars:\u003c\/strong\u003e With a 1.1 arc second Dawes limit, the AT126EDQ splits doubles that challenge smaller scopes. Epsilon Lyrae (the Double Double) is cleanly resolved at 150×. Zeta Herculis at 1.4\" splits with dark space between the components. Porrima (Gamma Virginis) and Castor are textbook pairs. The clean, high-contrast Airy discs that a good refractor produces make doubles one of its strongest visual subjects.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeep sky:\u003c\/strong\u003e 126mm gathers enough light to show real structure in the brighter Messier objects. M13 begins to resolve individual stars across its face at 150×. M42 shows the Trapezium as four clean stars with nebulosity streaming away from them. M57 (the Ring Nebula) shows its annular shape clearly with a hint of the central star under excellent conditions. The Veil Nebula complex responds well to an O-III filter. Galaxy hunters will see the dust lane in M82, the spiral hints in M51 with averted vision, and the bright cores of dozens of galaxies in Virgo and Coma — and the flat field means stars at the edge of your eyepiece field are as sharp as those in the center.\u003c\/p\u003e\n\u003ch3\u003eFor the Imager\u003c\/h3\u003e\n\u003cp\u003eThe AT126EDQ was designed with imaging in mind. At 882mm f\/7 with a flat field to full frame, it frames mid-size deep-sky targets with excellent image scale and sharp stars from center to corners without any additional corrective optics. The Rosette Nebula, the Crab Nebula, galaxy groups like the Leo Triplet, the Veil complex — these targets fill an APS-C frame beautifully at 882mm, and full-frame shooters get even more field to work with.\u003c\/p\u003e\n\u003cp\u003eAdd the optional ATEDQR 0.8× reducer and the system drops to 706mm f\/5.6. The wider field opens up larger targets — the North America Nebula, M31 with companions, the Heart and Soul pair — and the faster focal ratio cuts exposure times. The 56% increase in light per pixel means you can either shoot shorter subs or reach fainter structure in the same integration time.\u003c\/p\u003e\n\u003cp\u003eThe camera angle adjuster is standard equipment — rotate the camera to frame your target in landscape, portrait, or any angle in between without disassembling the imaging train. The focuser drawtube has a millimeter scale for noting focus positions, and the focus lock prevents shift during long exposures. The focuser is also compatible with electronic focusers like the ZWO EAF for remote focusing during imaging sessions.\u003c\/p\u003e\n\u003ch3\u003eThe Focuser\u003c\/h3\u003e\n\u003cp\u003eThe AT126EDQ's 3.2\" rack-and-pinion focuser is built for imaging loads. The right focus knob has a concentric 10:1 fine-focus knob for precise control — critical when you're dialing in focus on a camera sensor. The focuser drawtube terminates in a built-in camera angle adjuster that rotates a full 360° and locks at any position. This is standard equipment, not an extra-cost accessory.\u003c\/p\u003e\n\u003cp\u003eThe focuser provides multiple thread options: M63, M54, and M48. This gives you flexibility to connect reducers, filter wheels, and cameras without stacking adapters. The 2\" accessory holder uses non-marring brass compression rings — no thumbscrew gouges on your eyepiece barrels. A 1.25\" adapter is included for smaller eyepieces and accessories.\u003c\/p\u003e\n\u003cp\u003eThe drawtube has a scale marked in 1mm increments so you can record focus positions for different accessories. A lock knob under the focuser secures focus during imaging runs. The combination of smooth coarse motion, precise fine focusing, and a solid lock makes this focuser practical for both visual and photographic use without compromise.\u003c\/p\u003e\n\u003ch3\u003eBuild and Mechanical\u003c\/h3\u003e\n\u003cp\u003eThe AT126EDQ is finished in matte black anodize with black-anodized focuser and red accent appointments. The retractable dew shield slides forward from 28.6\" retracted to 34.7\" extended — functional for dew prevention and stray light control, and self-storing so there's nothing to lose or leave at home.\u003c\/p\u003e\n\u003cp\u003eThe scope ships with felt-lined hinged split mounting rings with M6×1 thread mounting holes in the top and bottom of each ring. A Vixen-style dovetail and a handle with a mini Vixen saddle plate are included. For heavier equatorial mounts, the rings accept a Losmandy-style D-plate dovetail (sold separately). A dovetail shoe on the upper focuser accepts optional finders or guide scopes.\u003c\/p\u003e\n\u003cp\u003eAt 17.67 pounds with rings, dovetail, and handle, the AT126EDQ needs a solid mount — an HEQ5-class equatorial or a ZWO AM5 will handle it for imaging. The heaviest single component is 15.6 pounds. The scope ships in a cordura nylon carry case with cutouts for accessories.\u003c\/p\u003e\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eAT126EDQ optical tube assembly\u003c\/li\u003e\n\u003cli\u003eFelt-lined hinged split mounting rings (pair) with M6×1 mounting holes\u003c\/li\u003e\n\u003cli\u003eCarrying handle with mini Vixen saddle plate\u003c\/li\u003e\n\u003cli\u003eVixen-style dovetail plate\u003c\/li\u003e\n\u003cli\u003e2\" accessory holder with brass compression ring\u003c\/li\u003e\n\u003cli\u003e1.25\" accessory adapter with brass compression ring\u003c\/li\u003e\n\u003cli\u003eRetractable dew shield\u003c\/li\u003e\n\u003cli\u003eFinderscope mounting shoe\u003c\/li\u003e\n\u003cli\u003eSlip-on metal dust cap\u003c\/li\u003e\n\u003cli\u003eCordura nylon carry case\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuadruplet optical system with two ED elements.\u003c\/strong\u003e Four-lens, two-group design: an apochromatic ED triplet objective plus a separate internal ED field-flattening group. Clean color correction and a flat field are built into the optical system — not added as an afterthought.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in flat field to full frame — no external flattener required.\u003c\/strong\u003e The internal ED field-flattening group delivers a 44mm corrected image circle. Stars are round from center to edge across full-frame (36×24mm) sensors. Skip the separate flattener and the spacing guesswork.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e126mm aperture at 882mm f\/7.\u003c\/strong\u003e The largest scope in the EDQ line. Enough aperture and focal length for detailed imaging of mid-size deep-sky targets and serious visual observing — planetary detail, double stars, and deep-sky structure.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFully multicoated optics.\u003c\/strong\u003e All air-to-glass surfaces carry antireflection multicoatings matched to their glass types. High light transmission, excellent contrast, and clean images free of color fringing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible with the ATEDQR 0.8× reducer.\u003c\/strong\u003e Add the dedicated reducer (sold separately) to drop from 882mm f\/7 to 706mm f\/5.6 — 56% more light per pixel, shorter exposures, and a wider field — while preserving the flat field.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e3.2\" dual-speed rack-and-pinion focuser with 10:1 fine focus.\u003c\/strong\u003e Beefy, precise, and imaging-capable. Coarse and fine focusing with ribbed knobs operable in gloves. Focus lock and mm-scale drawtube markings. EAF compatible.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt-in camera angle adjuster.\u003c\/strong\u003e 360° rotation standard — not an extra-cost accessory. Frame targets in any orientation without disassembling the imaging train.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eM63, M54, and M48 focuser threads.\u003c\/strong\u003e Multiple thread options for connecting reducers, filter wheels, and cameras without stacking adapters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNon-marring brass compression rings.\u003c\/strong\u003e Both 2\" and 1.25\" accessory holders use soft brass compression rings that grip without scratching your eyepiece or accessory barrels.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetractable dew shield.\u003c\/strong\u003e Self-storing — slides forward for use, retracts for transport. Controls dew and stray light without a separate accessory to track.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eObserving Tip\u003c\/h3\u003e\n\u003cp\u003eIf you're imaging with the AT126EDQ at its native f\/7 and you find yourself wanting a wider field or shorter exposures for larger targets, the ATEDQR 0.8× reducer drops you to 706mm f\/5.6. But don't overlook what f\/7 gives you visually while your camera is cooling down or while you're waiting for your target to clear the trees. At 882mm, a 10mm eyepiece delivers 88× in a wide field — plug in an O-III or UHC filter and sweep through Cygnus. The flat field means the stars at the edge of your eyepiece are as sharp as those in the center, which makes visual sweeping noticeably more pleasant than with a conventional refractor.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eDo I need a separate field flattener with this scope?\u003c\/strong\u003e\u003cbr\u003eNo. The AT126EDQ has a built-in ED field-flattening group that delivers a flat, corrected field across full-frame sensors. You don't need an external flattener — it's one of the primary advantages of the quad design. The only accessory optic you might add is the optional 0.8× reducer if you want a faster focal ratio and wider field.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mount do I need?\u003c\/strong\u003e\u003cbr\u003eAt 17.67 lbs with rings and dovetail, the AT126EDQ needs a mount rated for at least 30 lbs for imaging — an HEQ5 or EQ6-class equatorial, or a ZWO AM5. For visual use, the mount requirements are less demanding. A solid alt-az mount or a lighter equatorial will work, but this is not a grab-and-go scope.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat's the difference between the AT86EDQ, AT106EDQ, and AT126EDQ?\u003c\/strong\u003e\u003cbr\u003eSame optical design philosophy in three aperture sizes. The AT86EDQ (86mm, 602mm f\/7) is the grab-and-go option — light, compact, airline-friendly. The AT106EDQ (106mm, 742mm f\/7) is the mid-size sweet spot. The AT126EDQ (126mm, 882mm f\/7) is the largest — most aperture, most focal length, most resolving power, but also the heaviest and most demanding on a mount. All three share the quad design with built-in flat field and are compatible with the same ATEDQR 0.8× reducer.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan I use this visually, or is it imaging-only?\u003c\/strong\u003e\u003cbr\u003eThe AT126EDQ works beautifully for visual observing. The quad design was built around imaging, but 126mm of clean, well-corrected aperture delivers excellent planetary, double star, and deep-sky views. The flat field is an advantage visually too — stars are sharp to the edge of the eyepiece field, which makes sweeping star fields and open clusters particularly satisfying.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes this come with a finder?\u003c\/strong\u003e\u003cbr\u003eNo — a finderscope mounting shoe is included on the focuser housing, but you'll need to add your own finder or guide scope. This lets you choose the finder that matches your setup — a red-dot finder for visual, or a guide scope for imaging.\u003c\/p\u003e\n\u003ch3\u003eAccessories\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eATEDQR 0.8× Reducer:\u003c\/strong\u003e Drops the AT126EDQ from 882mm f\/7 to 706mm f\/5.6. Faster exposures, wider field, full-frame coverage. Designed specifically for the EDQ series.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eT-ring for your camera mount:\u003c\/strong\u003e Required for connecting DSLR and mirrorless cameras to the focuser's 48mm T-threads. Dedicated CMOS\/CCD astronomy cameras typically have 48mm T-threads built in and connect directly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinder or guide scope:\u003c\/strong\u003e The AT126EDQ ships with a finderscope shoe but no finder. Add a red-dot finder for visual use or a guide scope for autoguided imaging.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eZWO EAF electronic focuser:\u003c\/strong\u003e Compatible with the AT126EDQ's focuser. Provides motorized, software-controlled focusing for remote imaging sessions.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFinal Thoughts\u003c\/h3\u003e\n\u003cp\u003eThe AT126EDQ is the largest flat-field quad refractor in the Astro-Tech line — 126mm of aperture at 882mm f\/7 with a built-in ED field flattener that delivers round stars across full-frame sensors without an external corrector. For imagers, that means one less piece of glass in the train, one less spacing calculation, and one less thing to go wrong. For visual observers, it means 126mm of clean, well-corrected aperture with pinpoint stars to the edge of the field. Add the 0.8× reducer and you have two imaging systems in one scope — f\/7 for image scale on smaller targets, f\/5.6 for speed and field on larger ones. If you want a refractor that images flat out of the box and gives up nothing visually, and you have the mount to carry it, the AT126EDQ is the scope that does both without compromise.\u003c\/p\u003e\n\u003ch2\u003eTech Details:\u003c\/h2\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eModel\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eAstro-Tech AT126EDQ\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOptical Design\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eQuadruplet (4 lens \/ 2 group) with built-in ED field flattener\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAperture\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e126mm (4.96\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Length\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e882mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003ef\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eED Elements\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2 (one in triplet objective, one in field flattener group)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCorrected Image Circle\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e44mm (full frame and smaller)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCoatings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFully multicoated on all air-to-glass surfaces\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eResolution (Dawes Limit)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1.1 arc seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eVisual Limiting Magnitude\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e13.2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHighest Useful Magnification\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e248×\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e3.2\" dual-speed rack-and-pinion, 10:1 fine focus ratio\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Threads\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eM63, M54, M48\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCamera Angle Adjuster\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eBuilt-in, 360° rotation with locking knob\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAccessory Holders\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2\" and 1.25\" with non-marring brass compression rings\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDew Shield\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eRetractable (self-storing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (retracted)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e28.6\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (extended)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e34.7\"\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWeight (with rings, dovetail, handle)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e17.67 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eHeaviest Single Component\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e15.6 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eTube Finish\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eMatte black anodize with black and red appointments\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eMounting Rings\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eFelt-lined hinged split rings with M6×1 mounting holes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eDovetail\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eVixen-style (Losmandy D-plate compatible via mounting holes)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCompatible Reducer\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eATEDQR 0.8× (882mm f\/7 → 706mm f\/5.6)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eCarry Case\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eCordura nylon with accessory cutouts\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWarranty\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e1 year\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e","brand":"Astro-Tech","offers":[{"title":"Default Title","offer_id":41598481399881,"sku":"AT126EDQ","price":2699.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0573\/7974\/9961\/files\/126A.png?v=1756397309"},{"product_id":"astro-tech-at66edq-f-7-ed-quadruplet-apochromatic-refractor-ota","title":"Astro-Tech AT66EDQ f\/7 ED Quadruplet Apochromatic Refractor OTA","description":"\u003ch2\u003eAstro-Tech AT66EDQ f\/7 ED Quadruplet Apochromatic Refractor\u003c\/h2\u003e\n\u003cp\u003eWide-field astrophotography has one persistent problem: flat fields are hard. Most refractors—even very good ones—need an external field flattener to clean up the corners. Choose the wrong flattener, get the backfocus distance wrong, or grab the wrong extension tube, and you've spent $150 to $300 chasing a problem that shouldn't exist. The AT66EDQ solves this at the source. Its four-element quadruplet design produces a flat, sharp field across a full 43.2mm image circle without any additional accessories. No flattener math. No guesswork. The corners are sharp because the optics are designed that way.\u003c\/p\u003e\n\u003cp\u003eFour elements, two groups, air-spaced throughout—two of those elements are ED glass. One is FK-61, our long-established ED glass and the optical equivalent of Schott's FPL-51. The second is a proprietary glass we've kept confidential, for reasons we don't need to explain to anyone who's been in this hobby long enough. What we can tell you is that together they deliver genuine apochromatic correction across the full 43.2mm field at f\/7: sharp, color-free images without the fringing that follows most fast doublets. The 43.2mm image circle covers any 35mm full-frame sensor and most large-format CMOS imaging chips, which means this scope won't become the bottleneck if your imaging setup grows.\u003c\/p\u003e\n\u003cp\u003eAt 462mm and f\/7, the AT66EDQ is fast enough for broadband imaging without being reckless about focal ratio. Large emission nebulae, galaxy groups, and the sweeping star fields of the Milky Way all land at an agreeable scale. When you want to go wider—or when a faint extended nebula asks for shorter subs—the optional AT66EDQR 0.8× reducer (sold separately) brings the focal length to approximately 370mm at f\/5.6. That's roughly 36% faster, with the flat field intact.\u003c\/p\u003e\n\u003cp\u003eThe focuser doesn't ask you to compromise. A 2.8\" dual-speed rack-and-pinion gives you both the strength to handle a serious imaging train and the precision—via the 10:1 fine-focus knob—to land focus exactly where you need it. The drawtube is graduated in 1mm increments and terminates in a built-in 360° rotation adjuster, so framing changes happen at the focuser, not with a screwdriver at the ring interface. Threading options are extensive: M63, M54, and M48 male threads are all built in, along with a 2\" compression ring adapter with a non-marring brass ring. DSLR and mirrorless cameras connect via a T-ring for your specific mount (sold separately). Dedicated CMOS and CCD astronomy cameras—ZWO, QHY, Player One, and similar—typically have 48mm T-threads built in and connect directly, no T-ring needed. The focuser is also compatible with the ZWO EAF and similar electronic autofocusers.\u003c\/p\u003e\n\u003cp\u003eAt 3.6kg with rings and handle, this scope was sized for the instruments people actually own. It's at home on a harmonic drive like the ZWO AM5 or iOptron HEM27, on a portable platform like the Sky-Watcher Star Adventurer GTi, and in a carry-on bag. It makes a natural wide-field companion to a longer focal length setup—image with the AT66EDQ on one mount while you observe with the bigger scope beside it. The optics are optimized for imaging, but through a wide-field eyepiece and a good diagonal the views are genuinely sharp and color-free. This isn't a scope that makes excuses for its aperture.\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eFour-element quadruplet design, air-spaced.\u003c\/strong\u003e Flat-field correction is built into the optics. The 43.2mm image circle is sharp from center to corner without any external accessories. That's the job of a quadruplet, and this one does it.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eTwo ED glass elements — FK-61 plus one we're not naming.\u003c\/strong\u003e FK-61 is our long-established ED glass (Schott FPL-51 equivalent). The second element is proprietary. Both are there for the same purpose: genuine apochromatic correction at f\/7, across the full field.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFull-frame 43.2mm image circle.\u003c\/strong\u003e Covers all 35mm full-frame sensors and most large-format CMOS chips. The field stays flat and sharp edge-to-edge—critical for wide-field mosaics and large single-frame captures alike.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.8\" dual-speed rack-and-pinion focuser, 10:1 fine-focus ratio.\u003c\/strong\u003e Drawtube graduated in 1mm increments. Strong enough for a heavy camera-and-filter-wheel train. Precise enough to nail focus on a pinpoint star at high image scale.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBuilt-in 360° rotation adjuster.\u003c\/strong\u003e Frame adjustment happens at the focuser—no separate rotation adapters needed. Locks securely once you've found your composition.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eM63, M54, and M48 male threads built in.\u003c\/strong\u003e Plus a 2\" compression ring adapter with a non-marring brass ring. DSLR and mirrorless cameras use a T-ring (sold separately); dedicated CMOS and CCD astronomy cameras attach directly via their built-in 48mm T-threads.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eElectronic autofocus ready.\u003c\/strong\u003e Compatible with ZWO EAF and similar motorized autofocuser systems. Supports automated focus sequences and unattended imaging sessions.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eOptional AT66EDQR 0.8× reducer available.\u003c\/strong\u003e Sold separately. Reduces focal length from 462mm to approximately 370mm and f\/ratio from f\/7 to f\/5.6—about 36% faster. Flat-field correction holds with the reducer in place.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePortable imaging system.\u003c\/strong\u003e 3.6kg total weight with rings and handle. 343mm retracted (13.5\"). Fits harmonic mounts, portable equatorial platforms, and most airline overhead bins.\u003c\/p\u003e\n\u003ch3\u003eUnder the Night Sky\u003c\/h3\u003e\n\u003cp\u003eAt 462mm and f\/7, the AT66EDQ frames the targets that demand a wide field. M42—the Orion Nebula and its surrounding complex—fits with room to include the faint outer nebulosity that narrower scopes cut off. M31 (Andromeda) shows both dust lanes and the extended halo in longer exposures. M45 (Pleiades) frames cleanly with the reflection nebulosity visible against the brighter stars. The North America Nebula (NGC 7000) and the Pelican Nebula (IC 5070) frame together at this focal length. The Heart and Soul Nebulae (IC 1805 and IC 1848) fit in a 2-panel mosaic at 462mm, or in a single full-format frame with the 0.8× reducer.\u003c\/p\u003e\n\u003cp\u003eOpen clusters benefit equally from the flat field. The Beehive (M44), Double Cluster in Perseus, and Pleiades all look right when the stars are sharp to the edge. Visually, through a 2\" wide-field eyepiece, the views are crisp and high-contrast. The aperture is modest. The quality of what it does with that aperture is not.\u003c\/p\u003e\n\u003ch3\u003eObserving Tip\u003c\/h3\u003e\n\u003cp\u003eAim the AT66EDQ at the North America Nebula (NGC 7000) and frame the Cygnus Wall region. At 462mm it covers the full complex on a full-frame sensor—Wall, Gulf, Atlantic together. A narrowband Ha filter and 5-minute subs will pull up the hydrogen-alpha structure in a dozen frames. Add the 0.8× reducer and the Pelican Nebula (IC 5070) drops into the same frame. It's a single target that makes the case for wide-field, flat-field imaging better than any spec sheet can.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the AT66EDQ need a field flattener?\u003c\/strong\u003e\u003cbr\u003eNo. The quadruplet design handles field correction internally. The 43.2mm image circle is flat and sharp across the entire field without any additional accessories. The flattener is built into the glass—that's the whole point of a quadruplet.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the second ED element?\u003c\/strong\u003e\u003cbr\u003eOne element is FK-61, the optical equivalent of Schott's FPL-51. The second is proprietary glass we're not disclosing. The combination delivers genuine apochromatic correction verified across the full 43.2mm image circle. If you want to evaluate it, look at the corners under the stars—that's the honest test.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat cameras does it work with?\u003c\/strong\u003e\u003cbr\u003eDSLR and mirrorless cameras (Canon, Nikon, Sony, Fuji, and others) connect via a T-ring for your specific lens mount, sold separately. Dedicated CMOS and CCD astronomy cameras (ZWO, QHY, Player One, and similar) typically have 48mm T-threads built in and connect directly to the M48 threads on the focuser drawtube—no T-ring needed.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does the optional reducer do?\u003c\/strong\u003e\u003cbr\u003eThe AT66EDQR 0.8× reducer (sold separately) reduces the focal length from 462mm to approximately 370mm and the f\/ratio from f\/7 to f\/5.6—roughly 36% faster. That's a meaningful gain for narrowband or emission nebula imaging where photon-gathering speed matters. The flat-field correction holds with the reducer attached.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs this a visual scope or an imaging scope?\u003c\/strong\u003e\u003cbr\u003eIt's designed for imaging. The quadruplet flat-field correction, threaded drawtube, built-in rotator, and autofocuser compatibility are all imaging-oriented features. That said, the views through a quality 2\" wide-field eyepiece are excellent—sharp, color-free, and high contrast. It performs genuinely well for visual work, especially wide-field sweeping and star clusters. It just happens to excel at imaging.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat mounts work with it?\u003c\/strong\u003e\u003cbr\u003eAt 3.6kg with rings and handle, it fits comfortably on light-to-medium equatorial platforms. Harmonic drives—ZWO AM5, iOptron HEM27, Rainbow Astro RST-135—are ideal. The Sky-Watcher Star Adventurer GTi handles it without strain. Heavier mounts (HEQ5, EQ6-R) have no trouble either. It works with standard Vixen-style and Losmandy-style dovetail saddles via the included tube rings.\u003c\/p\u003e\n\u003ch2\u003eTech Details:\u003c\/h2\u003e\n\u003ctable style=\"width:100%; border-collapse: collapse;\"\u003e\u003ctbody\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eAperture\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e66mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Length\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e462mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocal Ratio\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003ef\/7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOptical Design\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eQuadruplet apochromatic refractor, air-spaced\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eED Glass\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2 elements (FK-61 + proprietary)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eImage Circle\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e43.2mm (full-frame)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e2.8\" dual-speed rack-and-pinion, 10:1 fine focus\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Threading\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003eM63, M54, M48 male; 2\" compression ring adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eFocuser Rotation\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e360° built-in angle adjuster\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (retracted)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e343mm (13.5\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f0f4f8;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eOTA Length (extended)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e420mm (16.5\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #ffffff;\"\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc; font-weight: bold; width: 50%;\"\u003eWeight (with rings \u0026amp; handle)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px 14px; border: 1px solid #cccccc;\"\u003e3.6kg (7.9 lbs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\n","brand":"Astro-Tech","offers":[{"title":"Default Title","offer_id":54541818855497,"sku":"AT66EDQ","price":849.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0573\/7974\/9961\/files\/66A.png?v=1750683292"}],"url":"https:\/\/astronomics.com\/collections\/quad-refractors.oembed","provider":"Astronomics","version":"1.0","type":"link"}