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It would be worth a test. Its not a big point but its worth talking about.
The trouble with the overblown stars is not that you've over curved them or anything, that data is now gone in the highlights. These CCDs with small wells spill over to surrounding wells or the surrounding wells in the weaker diffraction rings swell up too much.
I guess I see contrast more as the 16803 has 100,000 electron wells versus around 25,500 for the 8300. I didn't see these as a problem on your RC longer focal length shots because the narrower image spreads the flux over more pixels than the widerfield (I think I have that right).
If your tracking is super which your is then the gain in sharpness from less tracking error also helps give the image more snappiness I have noticed in my own 8300 images. I have quite a few using the TEC180 at F7 and there are too many with overblown bloated stars that tend to damage the image.
I would not say those overblown stars are wrecking the image just that instead of being overblown whitish stars they could have been nice features with nice colours. Perhaps at the expense of deeper detail?
I wonder what others' experience is on ideal exposure length. Marcus switched to 15 minute subs. I always used 15 minutes for subs but switched to 10 mainly because of the need for rounder stars not for overblown stars. I don't see any loss of reach or detail in later images using 10 minutes. Narrowband is different because Ha etc are so noisy they need longer exposures.
Greg.
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