Negative values on the histogram - what do they mean?

Posted by magnusl on Jan 03, 2022; 11:06am
URL: http://astroimagej.170.s1.nabble.com/Negative-values-on-the-histogram-what-do-they-mean-tp1713.html

Hi!

I'm getting some negative values at times in the histogram below the image when doing data processing with the DP module, see image



What do these negative values mean, really? Should I take them as an indication that my calibration process is problematic (for instance, that dark has been subtracted twice), despite the images looking good on visual inspection?

Magnus