iOptron GEM28 Go-To German Equatorial Mount with iPolar, and LiteRoc Tripod – G281A3
iOptron’s GEM28 series represents a new generation of compact German equatorial mounts that blend precision engineering with traveler-friendly portability. The G281A3 package includes the GEM28 equatorial head, the rock-solid LiteRoc stainless steel tripod, and the integrated iPolar™ electronic polar scope.
With a 28-pound (12.7 kg) payload capacity and a bare mount weight of just 10 pounds (4.5 kg), the GEM28 hits a sweet spot for astrophotographers and visual observers who demand performance without the back-breaking bulk.
High-Precision German Equatorial Mount Design
Engineered with a traditional German equatorial architecture, the GEM28 delivers superb tracking performance across both hemispheres. The mount is optimized for latitude ranges of 10° to 70°, with oversized mechanical controls for quick and accurate polar alignment—especially appreciated on chilly nights when gloves are required.
The GEM28A3 comes standard with iOptron’s iPolar™ electronic polar scope, a game-changing tool that allows you to polar align with arcminute precision—even when Polaris is hidden behind trees or not visible at all. Combined with the built-in bubble level and smooth azimuth/altitude adjustments, iPolar ensures that your mount is aligned and ready in minutes.
Advanced Engineering, CNC Craftsmanship
The GEM28 is constructed from a mix of precision CNC-machined and cast metal parts, delivering long-term durability without unnecessary weight. Both the right ascension and declination shafts are 30mm in diameter, riding on 144-tooth brass worm gears (88mm diameter) for smooth, low-backlash motion. The gear system is spring-loaded for consistent meshing, even under load.
The dual-axis stepper motors with integrated encoders provide 0.17 arcsecond per step resolution, and tracking rates include sidereal, solar, lunar, King, and a user-defined rate. That kind of versatility makes the GEM28 a natural choice for both visual observing and astrophotography. User-selectable backlash compensation is built in.
The mount offers nine speed levels for guiding and slewing:
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Guiding: sidereal and 2x sidereal
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Centering: 8x, 16x, 64x, 128x sidereal
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Slewing: 256x (1°/sec), 512x (2°/sec), and up to ~4°/sec
GoToNova® 8409 Controller: Precision at Your Fingertips
The included GoToNova® 8409 hand controller puts over 212,000 celestial objects at your command, from Messier showpieces to obscure galaxies and variable stars. The large 8-line, 21-character LCD display is backlit for night use, and the LED-lit buttons are glove-friendly. A built-in heating element keeps the screen readable down to -20°C (4°F).
The object database includes:
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Messier, NGC, IC, UGC, MCG, Caldwell, Abell, and Herschel catalogs
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Named stars, double stars, comets, asteroids, and variable stars
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88 constellations and user-defined entries
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More than enough to keep you exploring for a lifetime
Connectivity and Control Options
The GEM28 provides a variety of control interfaces:
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Wi-Fi built in for wireless control via smartphone, tablet, or PC
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USB port for wired control or firmware updates
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RS232 port with strain-relief for computer and ASCOM/INDI integration
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ST-4 autoguider port for plug-and-play guiding with your favorite guide camera
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HBX ports for auxiliary accessories or optional GPS modules
The mount is compatible with iOptron’s 32-channel GPS module and optional iGuider™ autoguiding system (sold separately).
Stable and Road-Ready
The included LiteRoc tripod features 1.75" stainless steel legs and a die-cast spreader tray, delivering excellent vibration dampening and rigidity in a surprisingly lightweight form. The tripod weighs just 16.5 pounds (7.5 kg), yet can support the GEM28’s full payload with confidence.
Payload and Balancing Notes
The GEM28 comes with a 10 lb counterweight, an 8" counterweight shaft, and a 5" shaft extension, all with a 20mm diameter. Combined, these allow proper balancing for telescope payloads up to 28 pounds. For best tracking performance during imaging, we recommend staying below 20 lbs instrument load to minimize flexure and settle times.
The mount accepts standard Vixen-style dovetail plates, giving you wide compatibility with refractors, small reflectors, and astrographs from most major manufacturers.
Observing Tip:
Even if you’re imaging with a guide scope, don't skip the iPolar alignment routine. A precise polar alignment not only ensures accurate tracking—it reduces field rotation, improves autoguiding results, and often eliminates the need for drift alignment. Think of iPolar as the shortcut that doesn’t cut corners.
Why Choose the GEM28 G281A3 Package?
If you’re looking for a precision GoTo mount that’s light enough for travel but strong enough for real-world imaging gear, the GEM28A3 delivers. With built-in Wi-Fi, belt drives, a wide database, electronic polar alignment, and an included hard case and tripod, this mount brings a level of refinement and convenience rarely found at this price point.
Whether you're heading to a star party or setting up in your own backyard, the iOptron GEM28 G281A3 gives you the tools to explore the universe with confidence.
