Bias PreProcessing Issues – #3 by colinttierney – Siril

I’m having some odd discrepancies between preprocessed and non-preprocessed stack results. My only preprocessing is a bias correction. For some reason, while the non-preprocessed stack ends up exactly as expected, the bias corrected one results in an image that has blown out highlights and zero shadow detail. In AutoStretch/using the Histogram Transformation, all the pixels across the scene are either on or off, with each color channel having slightly different values. That specifically seems like it could be a 16/32 bit conversion or aliasing thing, because when I run an intense Asinh Transformation I can recover a very small amount of highlight detail, but the shadows are still all obliterated. I’ve processed both sequences the same in multiple different ways, with the only difference being the bias adjustment. What could be the cause of this? Is the bias overcorrecting and removing good data? Any help is greatly appreciated, thank you!