Hi All,

Sorry for my slow progress and responses on the camera sensor analyzer tool. I've been trying to understand a problem in my process that impacts the results for Color sensors. (I'm fairly confident with the results on monochrome sensors).

When processing color camera data, it seems that white balance settings that are used when capturing the bias and flat images can impact the outcome of the analysis. For example, while testing my own ASI-178MC, I first used the manual white balance settings that I had established long ago, which produce mean ADU values for all color channels that are fairly even (as close as possible), WB Red 33, and WB Blue 92. The flat images appeared fairly neutral gray, (just slightly green). From this test, the resulting read-noise values from my tool were within 1% of those shown in ZWO documentation. But in a second test I set both WB Red and WB Blue to 80; the flat images appeared very red. From this test, the resulting read-noise values from my tool were generally lower (by around 3%), and the overall results over the range of gain values were less consistent (the read-noise curve had noticeable "bumps" that were not apparent in the test with white balance values that produced neutral looking flats).

My tool calculates mean values for each channel of the input data, so I should be able recognize if the input flat images are not "neutral". But I'm not certain whether I would be able to programatically compensate for this. If anyone has ideas on this, please let me know.

I had planned to develop a "front-end" process for my tool to perform the capture of the input files. In that process I might be able to control the white balance values to force the images to be neutral, but this development effort will likely take quite some time.

Thanks

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