I noticed on a couple of my photos taken at 1/2000 that the Blue channel had saturated (255) with the Red and Green remaining just short of saturation, around 245 – 252.
This appeared to affect the detail in the “hotter” (photographically) central region and led to a loss of contrast compared to the limb regions. I have significant vignetting in my system and this leads to a central hot spot with darker edges.
For my set up, I have noticed that the contrast of solar granulation and sun spots improves if I slightly under expose, to deliberately prevent the central region of the FOV from getting too close to the 255 values in the histogram.
Cheers
Dennis
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