It was minus 6 degrees Celsius when I captured this, and the cold Winter air felt delightfully quiet. Perfect for photographing the Mars opposition! I moved the telescope outside around 10 PM and started running the mirror cooling fan. Polaris was not visible from the spot where I can see the South, so I used the drift method in PHD2 to align the mount.
A focus test on Aldebaran showed fair seeing, maybe 5 or 6 on the Pickering scale. The out of focus image was reasonably calm but I can't tell whether the distortions are due to thermal effects (insufficient cooling) or seeing.
Then the first slew to Mars for adjustment of the ADC and fine focus on the planet surface. I used a gamma of 0.33 during focusing and the first raw video looked something like this:
Multiple videos were recorded over the course of the night using the Autorun and Ascom guide features of FireCapture. This enabled me to use a very tight ROI around the planet, and higher USB 2.0 FPS.
Technical:
Best 5% of 12 video's stacked with AS!3 using 1.5X drizzle. Color balance in R6, sharpening and final processing in PixInsight. All stacks were derotated with WinJUPOS. I originally blended in some unsharpened data to hide the edge-rind artefact on the right side of the disk. This was replaced with actual data from from a slightly different rotation of the planet (shot 4 days later) in Revision B.
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