Sky background brightness calculator

[drjolo]

Some time ago I created simple excel sheet to calculate sky background brightness on already done frames - now I translated it to English. You can measure it on any single calibrated subframe made with mono camera and luminance filter. All you need to do is measure some fragment of background level in ADU and fill other parameters in the sheet. 

 

I compared results I get with SQM meter and they look quite consistent in the range 19-21.5 mag/arcsec2. Values for NELM (naked eye limiting magnitude) and Bortle scale are estimated basing on calculated sky brightness. Maybe some of you will find it useful.

Sky Quality Calculator.zip