Quote:
Originally Posted by gregbradley
Lovely image Chris.
Star colours is the area I find these CMOS cameras weak in general and an area that really needs to be watched compared to CCD.
I am not sure why but many of these CMOS based camera images share this characteristic and the more colourful star images on Astrobin are invariably CCD cameras.
One approach that seems to work and is common with DSLR imaging is to use shorter exposures for the stars.
Its like imaging with too high an ISO with a DSLR. The stars end up all white with no colour.
It probably has to do with the fact that you can adjust gain on a CMOS which is most likely a lot higher than that on a CCD which then blows out the stars quicker than normal. The pixel sizes are also usually smaller to meaning smaller wells that fill more quickly (also due to the high QE of most of these sensors - not so much the 1600 though).
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Yes, all the above is true, but I have used shorter exposures. I'm almost certain the data is (mostly) ok, and that it was my processing at fault. I've still got a long way to go to learn (and practise) some techniques.
Quote:
Originally Posted by codemonkey
That's really nice, Chris, well done! The star colours do look a bit off, perhaps PCC in PixInsight might help with that?
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PCC failed to work for this image too, but I think I might have another idea to retry it next time around.
One of the hassles with all this processing is how long it takes. Even with my decent machine here, it takes hours to get to the point for the 4 channels of drizzle integration (this started with over 200 images per channel). Then I do all the processing on these larger drizzle images, and only resize when publishing, so each operation takes just that little bit longer. That's one of the reasons why I'm taking a break before having another go at this image for a reprocess. At least when I do, I can start at the drizzle images and go from there.
