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barx1963
25-10-2016, 12:52 PM
I managed to collect some data last night. I had some flats that I took on Sat night and the setup was the same so decided to use them to process. As an exercise I processed the same stuff (NGC1365) using just the Lum files both with and without flats. Image is a stack of 6x300s subs processed in DSS and given some moderately aggressive stretching in PS CC 2015.
First image only had darks applied while I went full hog on the second image, darks, flats, dark flats and bias frames.
No other processing apart from the stretch. I think the second image I went a bit further with the stretch to the point where a gradient can be seen(from local light pollution I think as the target was still fairly low in the east when I took the subs.)

Malcolm

Atmos
25-10-2016, 01:12 PM
Flats are probably the most important of the calibration frames!

KWR
25-10-2016, 01:31 PM
^^ Agreed. Although not hugely experienced, I'm finding flats, flat dark's, and dark's, are producing a more consistent and effective master, than when I include bias into the mix. Not sure why that seems to be at the moment.

Malcolm's pictures tell a thousand words.

rcheshire
26-10-2016, 04:40 PM
Good flats rule! Bad flats suck... Really, they are all important, bias dark and flatndark, for different reasons.