Quote:
Originally Posted by gregbradley
A proof of this is that one solution to this overly bloated star is to reduce exposure times so the wells can better contain the data further out from the star core without filling. I doubt its an APO issue as in my case for example the same scope does not show this behaviour with other cameras with deep wells (I have used quite a few cameras over the years).
Greg.
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good point - saturated star cores can result from overexposed subs - another one for the list Erik. The very simple answer, as you point out, is to reduce the sub exposures. There seems to be a residual belief that long subs are inherently better than short subs. This made sense in the days of CCDs with high read noise, where you needed lots of signal to get above the read noise - there are still some CCDs on the market that need long subs to work properly. Modern CCDs with small pixels have much lower read noise, so can be used with much shorter subs for the same SNR - if you use shorter subs, the wells do not saturate.
For example, your 694 needs subs about 1/3 as long as your 16803. A recent image by JJJ taken with 40 second subs shows just how far modern cameras have come.