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Mercury on 7th August 2020

5x Powermate
Baader 610 nm & IR-cut filters
ZWO ASI174MM camera
Mercury imaged early in the day during a short window of excellent seeing: Antoniadi II or better for about 15 minutes. Thanks to the high frame rate of the ASI174 camera I was able to capture a dozen video sequences before the seeing started to degrade, with a total of 120,000 frames. The percentage of good frames in a few of the videos was around 10%, which is exceptional for Mercury, and I was able to process the image entirely in software (PIPP, Autostakkert!3 and Registax 5) without having to resort to selecting frames by eye. The result shows a considerable amount of detail in the albedo features, and the resolution of the image is essentially at the limit imposed by the telescope, of around 0.4 arc seconds.
This is one of the best images of Mercury I have ever obtained, and provides a good demonstration of the fact that seeing is all-important in planetary imaging.