I’ve usual flat, dark, bias and light frames. I do the correct procedure as described here: https://discuss.pixls.us/uploads/short-url/y6K1nDx3zvKcGmZbyqvk7POzmLH.pdf (I actually coded that procedure in a siril script to use the command line).
Then, when it is time to register the lights, as my they are exposed for only 20s (it is m31, then I need different exposures to avoid blowing out the core), Siril is unable to register because it doesn’t find literally ANY star to do registration. This is not true of course, but I guess it has some threshold that makes it un-sensitive to 20-seconds stars (f6, ISO1600, 300mm focal lenght).
With the GUI I can select very small square in order to tell Siril to use that square to analyse stars, and strangely(?) it works (I draw the square just around a very bright star).
Now, one of the added value of Siril is the command line scripts. I really would like to solve this issue without any interaction with GUI. Is there any trick I could use ?
thanks in advance!