As a StarEx LR spectro enthousiast I have often struggled with choosing the right exposure time; trading off linearity with SNR. I burned quite a few nights to only learn the next day that some subs were saturated or of poor SNR.
So I vibe coded this utility program with Claude. It inspects acquired fits files in your science image folder as they come in - during your session (read only) or after. It does not provide reduction/calibration. Some features:
- detect if pixels in 2D target region are above linearity threshold of your CMOS/ADU, recommends exposure time for best SNR
- signal (spectrum) vs. background (light pollution) per wavelength
- session analytics trending: cumulative SNR : “when do you have enough subs?”, integrated flux & asymmetry (slit positioning)
- basic outlier detection, culling of files
- a simple log book; creates a text file next to your images
- day/night mode colors
I am using this alongside NINA, Sharpcap (but its agnostic))- tested it a few nights and I am happy with it. I am interested in your feedback/suggestions.
Did not decide yet if I want to maintain this over longer time, until then its free 
If you are not familiar with python - don’t worry; click in the install.bat file (with internet connection) and it will download and install and setup all things needed for you. You do not need coding skills to use this.
enjoy,
Matt