Explore Scientific FCD100 ED80 Triplet APO with 0.8x Reducer & iEXOS-100 GoTo Mount

Premium APO Glass Meets Wide-Field Astrophotography

If you’re serious about astrophotography, this package delivers. Explore Scientific has paired the FCD100 ED80 Air-Spaced Triplet Apochromatic Refractor with its 0.8x Focal Reducer/Field Flattener and the versatile iEXOS-100-2 PMC-Eight GoTo Equatorial Tracker Mount—complete with two extra counterweights. The result is a complete imaging and observing system that combines premium optics, fast focal ratios, and precision GoTo tracking in a portable rig.

The Telescope: FCD100 ED80 Triplet APO

The FCD100 version of the ED80 represents a significant step up in optical performance. HOYA’s FCD100 extra-low dispersion glass provides superior color correction and contrast, with excellent transmission in the red portion of the spectrum—where many emission nebulae shine brightest.

• 80mm aperture, 480mm focal length (f/6)

• FCD100 ED glass triplet virtually eliminates chromatic aberration

• EMD multi-layer coatings maximize transmission and contrast

• Enhanced red sensitivity brings nebulae into sharper relief

• 2.5" hexagonal rack-and-pinion focuser supports up to 10 lbs of imaging gear

• Compact tube design (91mm diameter) for easy transport

For astrophotographers, the difference is clear: sharper stars, higher contrast, and richer color saturation compared to standard ED glass.

The Focal Reducer: Faster Exposures, Wider Views

The included 0.8x Focal Reducer/Field Flattener transforms the ED80 from f/6 (480mm) to f/4.8 (384mm)—making it a true wide-field astrograph.

• Faster focal ratio means shorter exposures and deeper results in less time

• Flattens the field for crisp stars across APS-C and full-frame sensors

• Standard T-thread connection for DSLR or astro-camera attachment

• 55mm backfocus (+/- 2mm) ensures straightforward setup

This combination of premium glass and fast optics creates a 5-element imaging system (3 elements in the triplet + 2 in the reducer) that excels at wide-field targets like the Andromeda Galaxy, the Cygnus Loop, and the Heart & Soul Nebulae.

The Mount: iEXOS-100-2 PMC-Eight GoTo Tracker

The iEXOS-100-2 is a lightweight, portable German equatorial GoTo mount powered by Explore Scientific’s innovative PMC-Eight™ system. With wireless control and robust tracking accuracy, it’s the perfect complement to the ED80.

• 19 lb payload capacity (scope + accessories + counterweights)

• Wireless GoTo control via the ExploreStars app (iOS, Android, Windows)

• ASCOM compatibility for astrophotography control software

• German equatorial design for accurate star tracking with no field rotation

• Eight-core microcontroller ensures responsive slews and smooth tracking

• Glow-in-the-dark markings and built-in bubble level for nighttime setup

• Mount head only 9.45 lbs; tripod just 5.5 lbs — a highly portable rig

With the extra counterweights included in this package, balancing is easy, even with heavier cameras and accessories attached.

Cloudy Nights Community Insights

On Cloudy Nights, the FCD100 ED80 is frequently praised as a premium small-aperture APO:

• Owners highlight its tighter star profiles and higher contrast compared to the FCD1 version.

• Many astrophotographers describe it as a step-up instrument that reveals more structure in nebulae and brings more color saturation into their images.

• When paired with the 0.8x reducer, users report it as a fast, forgiving wide-field astrograph perfect for both beginners and advanced imagers seeking a portable rig.

• The iEXOS-100 mount is often described as surprisingly capable for its size, with the wireless GoTo system a favorite feature among traveling imagers.

What’s Included

• Explore Scientific FCD100 80mm Air-Spaced Triplet APO Refractor OTA

• Explore Scientific 0.8x Focal Reducer/Field Flattener (with T-thread adapter & end caps)

• iEXOS-100-2 PMC-Eight Equatorial Tracker Mount with WiFi & Bluetooth

• Travel tripod with accessory tray

• 99% reflective 2" diagonal

• 2.5" hex focuser with two extension tubes

• Hybrid Finder Scope Base (finder not included)

• Built-in dew shield & dust cover

• Four counterweights total (two standard + two extras)

Observing Tip

With the 0.8x reducer in place, the FCD100 ED80 becomes an f/4.8 wide-field powerhouse. Large emission nebulae like the Rosette, North America, or Veil Nebulae frame beautifully in its wide field. For visual observing, replace the reducer with the included 2" diagonal and enjoy razor-sharp lunar and planetary views with virtually no color fringing.

Final Thoughts

The Explore Scientific FCD100 ED80 APO with 0.8x Reducer and iEXOS-100 Mount is a complete astrophotography system that balances portability with premium performance. With superior glass, faster focal ratios, and precision tracking, this package is built for imagers who demand more from their gear while still valuing grab-and-go convenience.