I am in the process of taking flats, normally I don't use the auto debayering in the Fits Viewer, but in this case I did. I took the flats using Kstars 3.5.0 on my Rpi, using the white tee shirt method, the main camera is a fairly new ZWO ASI533. The "issue" shows up in the Fits Viewer on the Rpi and also if I load the file into the Fits Viewer on my laptop (same Kstars version) It is not file dependent, they all behave the same.
With auto debayering on I load a file. It looks flat, but I need to see the statistics to get the correct exposure. I turn on the Statistics tab and it looks like this:
the Red channel show a maximum of 42140, while Green and Blue show a maximum of 65532, the Blue mean is much lower than the Green or the Red.
I then look at the Histogram:
If I scroll over the right side peak, it shows Intensity levels as well as RGB frequency levels, however Blue frequency is zero. I am assuming the peak to the left are the Blue numbers, but scrolling over it shows nothing.
If I view the exact same image in ASISTudio viewer, the histogram there looks like this:
The mean values are roughly the same for the R, G numbers in the Fits Viewer, but here you can see Blue is also the same mean.
In any fits image I open the Red channel never has a maximum equal to the Blue and the Green (65532) for this camera. I think it must have something to do with the number of bits in the color image, as a processed jpg image shows all three colors at 255 maximum.
Or I don't understand how to use the Fits Viewer with Debayering correctly!
thanks for any feedback.