The right choice of Bayer pattern is crucial for correct colors, clean day images and error-free night image processing. Like almost all modern ZWO color sensors with Sony Starvis II technology, the ASI678MC uses an RGGB pattern. If this is set incorrectly or automatically recognized incorrectly, typical artefacts occur.
Below are the most important findings from the practical tests and the indi-allsky documentation.
Typical symptoms of a false Bayer pattern
- Checkerboard/mosaic structure in the image
- Gray, lifeless sky despite blue daylight
- Color casts (mostly green or violet)
- Reduced sharpness due to incorrect interpolation
- Exaggerated blue or red channels in bright areas
- Unnatural color temperature despite correct WB settings
If a false Bayer pattern is active, fotos looks like this:
Debayer test procedure (recommended)
- Test all four patterns one after the other:
RGGB, BGGR, GBRG, GRBG - Test each pattern in daylight:
Blue sky, objects with intense colors, direct sunlight - Evaluation logic:
Checkerboard → immediately wrong
Color cast or grey sky → wrong
Natural colors → correct - Night test:
Stars white/yellowish, background neutral dark, no color clouds
Result of the tests with the ASI678MC
RGGB is the correct Bayer pattern for the ASI678MC.
Reason:
- Corresponds to the official Sony IMX678 sensor layout
- Image immediately becomes color stable
- Gray daytime sky disappears
- No more artifacts
- Stable colors during the day and at night
- No more checkerboard patterns
GRBG, BGGR or GBRG should not be used with this sensor.
Recommended setting in indi-allsky
RGGB
This will ensure that
- correct color reproduction
- stable auto/manual white balance
- maximum sharpness
- clean day/night transitions
- realistic astronomy images