During my last cigarette break I took out my E-PL5 camera with Mitchie’s 20mm Lumix lens attached to it. Since it has an equivalent focal length of 40mm I took 9 images of the night sky at 10 seconds each, so I would still have round stars on each image, albeit in slightly different positions. Then I took one dark frame and one with the shortest possible time of 1/4000th of a second. I stacked them in DeepSkyStacker 3.3.2 on Windows, and later reduced the size of that stack to 4000×3000 pixels, and overlayed it over the first in GIMP (on Linux again) to see the differences. This is how it looks:
Well it seems that DSS does a terrific job with the alignment of those stars – they’re almost perfectly round, not worse than on a single photo. If I had masked out the foreground and used that from a single photo, and then if I had taken many more photos it would have been even better.
Interesting stuff, this. A 90 second total exposure with stars which are still round. Without any tracking.
Thanks for reading.