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Old 24-01-2010, 09:38 AM
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gregbradley
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Join Date: Feb 2006
Location: Sydney
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Also is there some reason you chose 5 minute subs? I don't think this is optimum for your chip.

There is an exposure calculator where you can calculate optimum exposure times for different cameras. For example an ST2000XM was around 10 minutes.

Here is one caclulator, there are others, I think perhaps on the SBIG site:

http://starizona.com/acb/ccd/calc_ideal.aspx

I use 10 minutes and that works very well except for bright objects.
15 minutes may be too long for this chip as it has small wells and I think that translates into bright stars spilling over when too long an exposure and makes them look bloated.

Unless you are having tracking problems I'd try 10 minutes.

Colour should be there already and not a matter of more time as well.

How are you processing the stars? There are ways to bring out the stars separately from the main object. Involved and I tend not to do it but there are techniques to create a layer with the stars only so you can process them separately. Or simply isolate the stars using the colour range tool and then increase saturation and use curves etc.

Or even easier use the Carboni action a few times (works a treat and nice and easy for the lazy processer). His reduce star size works fairly well to but it is based on the minimum filter which is a very limited tool and deconvolution is way superior.

Greg.
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