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True, true. Some very low noise CMOS sensors coming out for us to play with now and there's lots of noise on the overseas forums about very short exposures... could be some interesting times ahead.
I see QHY have listed some low read noise Sony CMOS sensors. I agree CMOS is likely to be the way of the future at some point. My Sony A7r2 mirrorless camera for example has read noise well under 1 electron per one test. Sony is concentrating on CMOS over CCD so I expect the advances to be more in that area. It would be great to get one of these Sony A7r2 sensors which is backside illuminated with copper circuitry and on chip analogue to digital converters in a mono version. If Sony ever bring out a mono camera like Leica have it could be a good one.
To be honest I expected I might get worse eccentricity at least, in the individual subs. I'd wondered though whether the stacking of those potentially less ideal individual subs might result in a better image though due to stacking algorithms being a bit more intelligent about what's rejected or included in the final integration.
I am not sure what intelligent stacking you are referring to as usually its quite simplistic like average or median. I do notice 2 x 2 binning to tends to round out stars as well.
Out of curiosity, with the 16803 you say it's hard to overexpose a star unless it's one of the "super bright ones." Do you have any idea what magnitude qualifies for "super bright"?
One thing I do get irritated by on my images is huge stars (mag ~9 or less at least). I've seen other images of the same targets with the same stars that appear much tighter, and yet I know my images are sharp (usually 1.8 - 2.2").
Its been my experience that small well cameras tend to show more bloated stars to what I think is the outer halo of the airy disc normally dim being brighter. But I think also because there is less bit depth in the star image itself and when you stretch the image the star data can break down more easily. Less so when its got greater depth as in deeper wells. That may not be a correct explanation but I do see my 16803 images as having much more robust stars that stand up to processing better than small well camera stars.
But there are also plenty of examples of excellent images with great stars from small well cameras so perhaps its more about the processing steps.
Greg.
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