Thanks David and Phil.
Phil I wish you could've been there too - hopefully next year?
Phil I tried dark frames a couple of times, but my darks never properly matched the lights for some reason - temperature difference? So when I subtracted them, I ended up with holes in my nebula.
So since then, I've always done them in-camera. I really love the results of it, but like you say - it's a whole lot of sky time where the camera isn't taking exposures.
Maybe I should give separate darks another try.
