I purchased my Losmandy G-11 mount way back in December 1993 in order to carry an Astro-Physics 105mm Traveler. Since then, I've used it to do deep sky astrophotography with an Astro-Physics 130mm StarFire EDF Refractor, and have photographed both solar and lunar eclipses with it. In the nearly 20 years I've owned it, the G-11 has remained one of the best values in its class. It is a particularly attractive choice for a precision equatorial mount that is truly portable and yet, can carry heavy payloads up to 60 pounds while maintaining a high degree of tracking accuracy and reliability.
After building Bifrost Observatory, I decided to add an outside concrete pad and pier for wide field photography in 2011. The G-11 is now semi-permanently mounted on this pier where it remains in perfect polar alignment and ready for use with just a few minutes of preparation. The periodic error of the G-11 Worm Gear typically about 10 arc-seconds peak-to-peak over a 4-minute cycle. This excellent for a portable mount. When doing wide field astrophotography with the G-11, it isn't even necessary to use a guide scope for the typical exposures of 2 to 6 minutes.
New versions of the G-11 are also available with GOTO options, but the original model serves me well and is a solid workhorse.
The table below contains the technical specifications on the Losmandy G-11. For more information, see the Losmandy web site.
| SPECIFICATIONS OF G-11 MOUNT SYSTEM | |
| R.A. Gear Wheel: | 5.625", 360 tooth 7075 T35 aluminum |
|---|---|
| DEC. Gear Wheel: | 5.625", 360 tooth 7075 T35 aluminum |
| DEC. and R.A. Worm gear: | 440C Stainless (54 Rockwell hardness) |
| Worm gear support: | Dual supported ball bearings |
| Worm gear coupling: | Oldham |
| Laser Engraved Setting Circles: | Porter Slip Ring design, 5" DEC. and R.A., |
| Right ascension resolution: | 4 minute increments, pointer |
| Declination circle resolution: | 1 degree increments, pointer |
| R.A. Axis Needle Thrust Bearings: | one 3.75", one 2", and two 1.625" |
| DEC. Axis Needle Thrust Bearings: | one 3.75", one 2", and two 1.625" |
| DEC. and R.A. Clutches: | Slip clutch, variable friction, one knob ea. axis |
| Latitude Tangent Arm range: | 12 to 64 degrees with polar scope, 8 to 68 with minor modification |
| Azimuth adjustment range: | +-8.5 degrees |
| Dovetail Saddle Plate: | "D" Series Standard |
| Weight of Mount Head | Approximately 31 lbs. |
| Weight of Field Tripod | approximately 20 lbs. |
| Semi-Pier Tripod Height | 34 to 48 inch |
| Load Capacity: | Approximately 60 lbs. |