After creating my recent image of the
Moon, I realised that the clear conditions provided a good opportunity to create a little movie to demonstrate the effects of seeing.
Making this 'little movie' turned out to be a lot more difficult than I expected ...
My original goal for the evening was to get just one good 'lucky image' of the Moon, so I captured 299 x 10mS subs using sidereal tracking, never intending to stack the subs. This gave me a great series of clear images, but lunar motion meant that the centre of the Moon moved slightly from one frame to another - which sees the Moon whizzing along when the subs are compiled into a movie. So, I needed to register the subs first.
Pixinsight did a reasonable job of registering many of the subs, but struggled with others because they did not have enough stars - perfectly understandable for 10mS exposures.
Affinity Photo did a great job of registering all the subs, however it also scaled them to keep the Moon within a fixed envelope - not exactly what I needed for this project. So I used Affinity to create a blank document, placed all 299 subs as layers, then manually aligned each layer using a tiny crater with a clear shadow near the centre of the lunar disk. Then I created a slice to crop and export each layer, then used Graphic Converter to compile the exported images into a movie.
Although the original movie does a great job of visualising the seeing, it really needs to be displayed at a size larger than is possible here on Astrobin. So I created a new crop along the terminator on the right hand side of the image, which I uploaded as Revision B.
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