Can I re-preprocess after running script

First time user and so far thrilled with results - ran 1032 untracked lights of M31 with the automated preprocessing script via the first steps tutorial - the end product is fantastic but the composition is wrong. I think I needed to pick a reference frame? How do I choose a reference frame and can I restack without having to run the whole script and register again??

Thanks

Welcome!
This is absolutely a correct way to proceed, running the default script and if not to taste then retrying a few steps manually, for framing or stacking parameter adjustment.

You can change directory to the process directory that was made by the script, there you will find different image sequences: the calibrated images, named with prefix pp_, the rotated images with prefix r_. You can open the calibrated images’ sequence and select a new reference using the sequence image list from the sequence tab.

See our tutorials for more information, in particular the manual preprocessing one.

Excellent! Thank you so much.