Taken from a Bortle Red/White zone, this image is 40 sub-images of 120 seconds each at ISO 800.   This is double than what I was able to do before.   The inclusion of an IDAS-LPS drop-in filter for my Canon T3 allowed this one stop of extra exposure.    So, now I know how much the drop-in filter blocks, which is quite a bit.

Regardless of the above, the gradients and the color shift from removing that much LP still make processing difficult and tedious.  I am glad I can drive just 30 minutes and get to a spot dark enough to be camera noise limited instead of skyfog limited.  It is such a joy to process images that have low LP levels.    🙂