CGEM/CGEM DX Mount additional specifications
February 20, 2018
These measurements are for the CGEM. CGEM DX mounts are very similar, differing mainly for the tripod and the counterweight shaft measurements.
Counterweight shaft thread into mount: 5/8”x12
Height of equatorial head without OTA: it depends on latitude. At 30° latitude the head from tripod top to top of dovetail clamp in equatorial north position is ≈ 22”.
Center of pivot (orange) to center of dovetail clamp surface depends on latitude. At latitude 45 it is ≈ 14”.
Tripod height in low position: ≈ 28-1/2”
Tripod height in high position: ≈ 50”
Tripod spread in low position is ≈ 32”
Tripod spread in high position is ≈ 54”
The CGEM DX tripod in low position is 40" to the top of the adapter plate or bell. Height of equatorial head without OTA: it depends on latitude. At 30° latitude the head from tripod top to top of dovetail clamp in equatorial north position is ≈ 22”. Total height in this configuration is ≈ 66".
The CGEM DX center rod (supporting the accessory tray) has M12 x 0.75 threads.
Base of mount to pivot center (orange) ≈ 5”
Pivot center (orange) to center polar axis ≈ 4”
Center of polar axis to dovetail clamp surface ≈ 8”
Span from end of standard counterweight shaft to dovetail clamp surface ≈ 23”
Periodic error: in the range 15-25 arc-seconds peak-to-peak
Drive gear is 180 teeth 3.6” diameter
Screws (3) attaching dovetail clamp to equatorial head are 6 mm M6.