Taking design cues from their venerable CEM line of EQ mounts, the iOptron GEM45EC Equatorial GoTo Mount gets an upgrade from the standard GEM45 mount that brings the periodic tracking error down to less than 0.25 arcsec, made possible through the use of high-resolution encoders and their Real-Time Periodic Error Correction (RPEC) system. The encoders and RPEC continuously monitor the tracking accuracy and make any necessary corrections as soon as they are detected. This is an invaluable upgrade for astrophotographers who practice long-exposure techniques to keep their star fields tack sharp without streaking or blurring.
The encoders are mounted on the mount's high-resolution motors, and a precision synchronous belt transmission reduces vibration. The mount boasts a payload capacity of 45 pounds, without the included 11-pound counterweight, to handle most optical tube assemblies (OTAs) and accessories, including heavier photo rigs and filter wheels. iOptron's Universal Self-Centering Saddle (USCS) accepts both Losmandy and Vixen-style dovetail plates, so it can handle just about any configuration of optical tube and gear you have. This version of the GEM45 includes the motorized mount, the Go2Nova 8407+ computer hand controller, a iPolar electronic polar finder, the rock-steady LiteRoc stainless steel tripod, and a hard carrying case to safely transport and store the mount head and accessories like cables and the controller.
The center-balanced design of the mount head places most of the optical tube's weight over the mount's center of gravity, resulting in greater stability, smoother movement, and quieter running versus standard designs. An included 32-channel GPS receiver transmits accurate date, location, and time to the hand controller, so when you change your position, the telescope can be set up quickly with accurate information and little input from you.
The mount is controlled by the Go2Nova hand controller. This system has an internal database of over 212,000 celestial objects, multiple assisted alignment procedures, and updatable firmware through the built-in serial port. With nine slew speeds and automatic tracking capabilities, finding and keeping objects centered in the field of view is easy whether you're viewing the fast-moving moon or much slower deep-space subjects.
- German equatorial configuration provides smooth and accurate celestial tracking for observation or astrophotography
- Center-balanced "Z" design places the weight over the mount's center of gravity to provide greater stability, smoother movement, and quieter running while requiring less counterweights
- 45-pound payload capacity, excluding the included counterweight
- 14-68° latitude; ±6° azimuth adjustment range
- Capable of tracking 0-20° below the horizon for hilltop/balcony use with automatic meridian flip
- Integrated iPolar electronic polar finder works globally; no Polaris (north) or Sigma Octantis (south) necessary; no need to rotate the mount during alignment
- 32-channel GPS receiver for accurate day, date, time, and location information
- 5" Universal Self-Centering Saddle (USCS) accommodates Losmandy and Vixen-style dovetail plates
- Counterweight bar with 11-pound counterweight enables proper balancing of an optical tube and accessories
- Real-Time Periodic Error Correction (RPEC) system with high-resolution encoders continuously and automatically identifies and corrects intrinsic tracking errors to constantly improve accuracy over time; <0.15 arcsec tracking error
- Precision tracking with less than 0.25 arcsec error
- 1.8° stepper motor with 128x microdivision and precise 0.08 arcsec resolution
- 110mm, 216-tooth right ascension (RA) and declination (dec) worm wheels with zero backlash
- 68mm RA and declination ball bearings provide smooth movement with minimal vibration
- 45mm steel RA and dec axis shafts
- Synchronous belt transmission improves tracking accuracy, with reduced vibration, especially with heavy loads
- RA and declination gear switches release the gears for balancing OTA
- Precise 0.08 arcsec (200 pulse/sec) motor resolution
- Low-power consumption: 0.6A (tracking), 0.9A (using GoTo)
- Runs on included 12 VDC 5A power adapter; plugs into a standard 110-240 VAC North American outlet
- 212,000+ object database includes the moon, sun, planets, stars, comets, asteroids, and constellations
- Multiple assisted alignment procedures use the built-in GPS module and iPolar electronic polar finder
- Slew speeds: 1x, 2x, 8x, 16x, 64x, 128x, 256x, 512x, MAX (4.5°/sec)
- Real-time periodic error correction (RPEC) uses digital encoders on the motor drive system to detect and correct tracking errors as they occur, then "remembers" the corrections to make the system more precise every time it is used
- Tracking rates: Sidereal, Lunar, Solar, King's, user-defined from 0.99x to 1.01x of Sidereal
- Star Identification function will tell user what star the mount is pointed at after proper alignment
- Computer control with planetarium software via integrated autoguiding port
- Control for optional electronic focuser
- Control optional illuminated polar scope light intensity
- Fully compatible with mount's integrated GPS module to automatically determine day, date, time, and location
- Serial port for firmware upgrade
- Adjustable key and display brightness
- Integrated heater that ensures the LCD display will work at temperatures as low as -4°F (-20°C)
- 8-line/21-character LCD screen; backlit 19-button user interface
Database details:
- Solar system: 9 objects, including the sun, moon, planets (& Pluto)
- Named objects: 92 deep-sky objects with their common names
- Messier catalog: 110 objects
- NGC catalog: 7840 objects
- IC catalog: 5386 objects
- PGC catalog: 73,197 objects.
- Caldwell catalog: 109 objects
- Abell catalog: 4076 objects
- Herschel catalog: 400 objects
- Named stars: 259 stars with their common names
- Double/multi stars: 208 stars
- Hipparcos catalog: 120,404 stars
- 88 modern constellations with their names
- 15 comets
- 116 asteroids
- 60 user-defined objects, including comets
- Innovative design provides the stability of a large 2" tripod, but with lighter 1.75" diameter legs
- Specially designed leg cuffs and sockets and locking levers add rigidity with less wobble when legs are fully extended
- Spreader locks legs into position to add stability and vibration suppression
- Minimum height: 30" (76.5 cm)
- Maximum height: 47" (116.8 cm)
- Weight: 15 pounds
- Safely carry, transport, and store mount head, hand controller, and counterweight shaft
- Aluminum case with reinforced corners
- Dual latches
- Molded hinged handle
- Foam-lined lid and custom-cut foam insert prevent items from shifting