Moravian instruments, Inc., source: https://www.gxccd.com/art?id=720&lang=409, printed: 01.05.2025 1:13:19

Main page▹Product Overview▹Astronomical cameras▹Articles

6.3.2025
C3 series and C2-9000 cameras with GPS receiver module
 GPS satellite signal receivers provide not only location information, but also can be a source of very precise (sub-microsecond) timing information. Integration of the GPS receiver with an astronomical camera thus allows very precise timing of exposures. Geographic location data, also available to the control software through specific commands, is an added bonus. The new variants of C3 as well as C2-9000 cameras can now be supplemented with a GPS receiver. The GPS module port on C2 and C3 cameras is identical to the one used on C1× and C5 cameras, so all Moravian Instruments camera lines use the same GPS receiver modules.

C3-61000 PRO (left) and C2-9000 (right) cameras with installed GPS receivers

C3-61000 PRO (left) and C2-9000 (right) cameras with installed GPS receivers

GPS modules can be attached to the port on the back side of the C2 or C3 camera head. Please note the camera must be equipped with a different back shell as well as internal electronic circuits to be compatible with GPS modules. So, it is necessary to choose GPS-ready variant upon camera ordering. Adding a GPS later requires the camera to be sent to manufacturer.

GPS antenna is shipped with the GPS module. Antenna cable is 3 m long and the antenna is equipped with a magnet, allowing it to be attached to any ferromagnetic surface. Please note the antenna must have a good view to the sky to be able to acquire signal from GPS satellites. Placing the antenna e.g. under metal covered dome may significantly limit the GPS signal reception.

GPS receiver module handling

GPS module is handled through camera command set. Its main purpose is to provide very precise timing of the exposure times with better than μs precision (the GPS module provides time pulses with 30 ns tolerance). Geographic location data are also available to the control software through specific commands.

The GPS tab in the SIPS camera control tool window shows information about GPS receiver state

The GPS tab in the SIPS camera control tool window shows information about GPS receiver state

The GPS module needs to locate at last 5 satellites to provide exposure timing information. Geographic data are available if only 3 satellites are visible, but especially the mean sea level precision suffers if less than 4 satellites are used.