[raymo]

Thanks Leon, Rocky, and Alex.
Sorry to disappoint you Dunk, but I have only ever used JPEGs; RAWs, TIFFs,
FITs, MOVs, AVIs, etc etc etc, they do my octogenarian's head in. I have
also never used flats, biases, or done my own darks, just not used darks, or enabled in camera noise reduction, also did all my processing[apart from sharpening] in DSS. No layers, masks, gradient removal, deconvolution [don't
even know what that is].
raymo