G4 cameras are capable to use large CCD detectors with 36 × 36 mm area, which is 50% more than the area of classical film frame. Precisely regulated cooling keeps the CCD on constant temperature, which allows quality image calibration. Cameras can be equipped also with liquid-coolant heat exchanger to cool down the hot side of Peltier TEC modules, beside the two magnetic levitating fans used in air cooled cameras.
There is a mechanical shutter inside the camera head, filter wheel for 50 × 50 mm square filters (round filters of 50 mm diameter cause vignetting on such large CCD chips) cannot be placed inside the camera head due to limited space. But it is possible to connect external filter wheel for 5 large filters to the G4 camera, the camera head already contains connector for external filter wheel control.
Used CCD detectors are equipped with so-called Anti-Blooming Gate (ABG), which drains the over-abundant charge from saturated pixels. ABG ensures the round images of bright stars, without disruptive blooming spikes. On the other side, compromising of the CCD linearity by ABG is only negligible. G4 cameras can be used for astrometric and photometric applications as well as for astrophotography.
Model CCD ABG Color mask Resolution Pixel size Chip area
G4-9000 KAF09000 yes none 3072 × 3072 12 × 12micron 36.9 × 36.9 mm
G4-16000 KAF16803 yes none 4096 × 4096 9 × 9micron 36.9 × 36.9 mm
Camera handling and image processing software SIPS
SIPS (Simple Image Processing System) is a powerful software package for camera control and image processing.
- Complete control of both imaging and guiding cameras, filter wheel handling and sequential exposures.
- Image native format is FITS, export to PNG, JPG, TIFF, GIF formats, recording of AVI sequences.
- Advanced automatic guiding with sub-pixel precision.
- Simple as well as complex image calibration, handling of whole sets of images at once.
- Automatic registration and stacking of images.
- Image basic operations (adding, median, ...), advanced multi-pass debayer processing of images taken by color CCD detectors.
- Astrometric image reduction.
- Telescope mount control.
- Data read from GPS receivers, synchronization of location and observing time.
- and many more functions.
SIPS software package is available for download for free from www.gxccd.com.
Also available are Gx camera drivers for MaxIm DL and AstroArt software packages as well as ASCOM universal drivers.