With an above average seeing forecast for 2100 to 2300, and not wanting to be up all night again, I went out for a capture of Mars at 2050. I also wanted to check for focus difference between IR, R, G and B filters.  

The same set up that I used the night before was still in place. I used it without any changes. Also, I did not check polar alignment.

The temperature was 44 degrees and RH was 57%. I was not expecting dew, so I did not turn on the dew heater. I wore my regular boots, ski pants, and heavy blue jacket over regular clothes and was very comfortable for the hour that I was outside. I could have worn sweat pants and sweat shirt underneath if it had been colder. I will be looking for a colder night to see if I can stay warm with the extra layers.

After getting the equipment powered up, and slewing toward Aldebaran, I had to wait maybe ten minutes for it to clear the trees. Using the Bahtinov mask, I checked focus across all four filters. I did not find a need to focus between filters.

Next I slewed to Mars, and had to wait another ten minutes for it to clear the trees. I found that that seeing in the FC display appeared to be mostly above average, with brief periods below average and brief periods of excellent seeing.

I did two sets of captures for Mars, one with a 60% histogram and another with a 80% histogram. The purpose of this is to try to eliminate clipping in the bright polar cap region. Both sets of captures were 90s per IR, R, G, and B filter, ROI was 408 x 348, and frame rate was 512 fps. I intend to produce and IR and an RGB image from each set of captures. Shutter was 1.1 to 3ms.

For the 60% set, gain was 385 and about 12k frames per filter were captured. For the 80% set, gain was 400 and 46k frames per filter were captured.

There were no difficulties in getting set up or in operating the equipment. This was a very enjoyable session

Mars - 2022-11-24 02:38 UTC - 60% Histogram

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