David - it's not the alignment per se that's the problem, it's that they're at different exposure times.
During image acquisition, i initially dialled up a series of 4min subs to finish about 11pm as i was expecting cloud from about midnight onwards. however with no sign of clouds i thought I would set up another set of subs, this time at 8mins. So, i have a ~3hr set of lights/darks at 4mins, and a ~3hr set of lights/darks at 8mins (plus flat and bias masters).
I've still got my Pixinsight trainer wheels on, but what im looking for is the best way in Pixinsight to combine those two sets of subs.
Anyway, thanks for all the tips guys - i'm learning heaps
