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Andy took me up on my offer and provided subs for me to chuck into APP.
This is NOT a "my processing is better than yours" exercise. Andy is at crossroads of where to improve and hopefully I can help him decide. My original thought was APP could greatly improve the nebulosity. More like its shown how badly I understood the target brightness.
So the piccies. Attached are three pics.
First pic is a rotated and cropped image to match original posted pic. This image was processed from Andy's first set of subs he provided, using AstroPixelProcessor with its default settings except using sigma rejection. Its the default autostretch when you view a file (in this case the stacked integrated image) and then saved to JPG. No other processing except resizing to get small enough filesize to upload here. Lights, flats, darks, bias were used.
Second pic is same result autocorrected in photo editing program.
Third pic is source FITS from APP processed in Pixinsight with only a histogram stretch just to show how much nebulosity and structure is hiding in the data still.
My thoughts are I was hoping by default to see more nebulosity than I got but still i think APP with defaults did a great job of producing a cleaner result to work with than DSS. There are more and better options for processing and noise reduction during the regiostration and integration process available before you can start post processing. I find for my needs the default autostretch of APP gives me a great result with good colour but if I want the best I can do I can take the fits file into PixInsight but usually I prefer the whole workflow in PI myself and use APP more to do a quick process of a new data set to make sure I got what I was after and its worth the time and effort of PI.
Interesting the ugly streaking didnt really exagerrate at all so I think its more from a source out of shot rasther than sensor reflection so perhaps a shroud is neededto keep from optical element in shadow?
I dont think noise is a major problem with the cameraeither as the unfeasable stretch in PI still shows fairly clean nebulosity even though other noise is vastly obvious. To me this shows with some masking techniques and star reduction there is room to bring more nebulosity structure and colour forward which will be tricky but doable.
My conclusion is processing is where improvement is most likely, though of course better gear will help as always but then you have the processing limitation still.
Anyway its 3:25am and I still have more of Andy's data to play with and respond to him with but for now wanted initial thoughts re original post put down before i forget them. Discuss ?
steve
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