As far as I understand, ShotCut does not work with (resolution-reduced) proxy-files for editing. With this in mind, I would like to address a question further below in a general manner, where I could not yet find the answer.
In my case I want to edit two cameras (differnet angles) on two Video tracks (1080p, 30/60FPS), plus one Audo track.
Currently the preview (playing the Videos in the Editor) is very laggy. I am on Win 8.1 64bit with 8GB Ram and I7-4500U CPU and Shotcut-Version 19.06.15.
The current try with H.264-Files is very laggy and I am considering re-encoding to other formats prior editing.
I have been using VideoStudio, which seems to handdle these files better under a performance aspect, but there are reasons, that VideoStudio in not at all an option for me - I have way too many issues for a paid software and therefor I want to participate in the Open Source software-movement, if possible.
So the general question: Which are the best (performance wise) file formats (Audio and Video) I should convert my source clips to prior editing, to have the best performance and as little lag (CPU usage) as possible during editing?
Is ProRES suggested for Video, or something else?
Am I maybe missing some settings, which could increase performance during edition and playing the clips?
What are Your codec-suggestions for Video and Audio, if the best performance (least CPU usage) is focussed?