I live in the most danged-terrible LP area known to humanity and I still image Ha-LRGB (OSC) - as Peter mentioned, PI removes 99.9% of the problem.
I do NOT use a single LP reduction filter either (not counting the Ha filter
). My MINIMUM exposure length I do is 10 minutes per sub.
I make the most of what I have, and do NOT travel anywhere further than my side-yard to image (if I take a 1 sec exposure at night with my DSLR it is red). I know my images might improve a LOT if I did, but I have no desire to go out bush any more - minimum 1 Hr from Canberra.