Quote:
Originally Posted by The_bluester
Regards different methods. I have found some data sets quite tolerant of calibration with a master bias and master flat (Which itself is produced from flats calibrated with the same master bias) but on others it led to brightened corners. Typically narrowband or LRGB images where I am trying to get away with the shortest subs I can, so the background is only just above the noise floor, master flat/master dark calibration proved better on some of those.
I have not found a data set of my own where calibrating with a master dark and master flat that that was calibrated with a master bias is worse than using a master bias instead of master dark, so I just do everything that way now. But everyone is free to use whatever process gets them a result they are happy with, many ways to pluck that running chicken!
|
My experience as well. Flats can be touchy and very often need the correct dark and bias with it to work well.
Sony ICX694 CCD sensor and the KAI16200 CCD are pretty clean and often just needed a bias and perhaps a flat for the KAI sensor as its larger.
Small sensors may not even need flats as vignetting should be minimal.
Greg.