Quote:
Originally Posted by gregbradley
One weakness with the super short subs is the need to go 8 bit to keep file sizes manageable.
This will reduce dynamic range like that M51 shot with the badly blown core.
Or could that have been avoided?
Greg
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the dynamic range scales with the number of subs. If you have 2000 subs with 8 bits (256 levels) dynamic range and stack them, the final result will have 2000x256 possible levels, which is actually pretty good. Planetary imagers routinely stack huge numbers of 8 bit images and end up with much more than 8 bit dynamic range. On dim targets it is not unusual to have only 5-6 bit data - it still stacks out to much better than 8 bits dynamic range.
You would not necessarily use really short subs for DSOs - broadband optimum would be maybe 10-30 seconds with a fast scope.,