The first half of last night was clear in Brisbane, but of course it's quite near a full moon. Time for doing some narrowband imaging.
This was my second target for the night - my other one is still a work in progress and needs a lot more data. For this one, I wanted to try high gain, short exposures and lots of them. Here's the details:
Sharpstar 107PH with 0.67 FR (f4.4)
ZWO ASI1600MM-C at -15C
91 x 30 sec Ha at Gain 200, offset 50
60 Darks
Much larger version is here:
https://flic.kr/p/SQPfix
Processed in PixInsight. Open to CC/suggestions to improve it as I didn't really do much to it (DBE, DynamicCrop, Rotation, HistogramTransformation). The cropping is slight to remove vignetting in the corners (I'm awaiting a connector to hopefully reduce this further).
There's some weirdness to the star shapes that look as if it's some form of trailing error (or bad registration?). I was guiding and PHD2 seemed quite happy. I can't pick the problem in individual frames (using Blink), but maybe I'm missing something. I'll go back over those frames again to see if I can uncover anything else, but I'm open to any ideas?
Finally, I think that I do not have the spacing 100% correct and there's some curvature near the edges - especially near where it vignettes. After I get the connector to reduce the vignetting, I'll try to eliminate this problem too.