Once again the PicGoto Group comes through! I posted a question about using the PicGoto to track at lunar rate, and Ángel Caparros replied with what I should have thought of: lunar rate = sidereal rate x (1 - 1/29), because the moon makes one orbit approximately every 29 days. So I input that as the RA timer tick and saved it to the PicGoto EEPROM, then used the PicGoto to track the Moon at lunar rate while imaging the lunar eclipse. Tracking was not perfect; I kept needing to nudge to the northwest, but it was pretty good.
Imaging the eclipse proved to be difficult; I knew there would be issues with the brightness of the Moon changing so much. I ran two imagers: my Meade DSI Ic on my 9 x 50 guide scope (this is normally my guide camera) taking single frames every 2 minutes, and my Meade LPI with a minus violet (Baader Fringe Killer) filter on the ST-80 scope taking 1 minute of 12.5 fps video separated by 5 minute intervals; with this one the Moon just fits in the field of view. I have produced an animated GIF from the DSI images, shown below. Exposures ranged from 0.001 s with the camera gain turned way down for the full Moon, up to 0.4 s at full gain during totality. Places where the animation seems to pause or even reverse are times I made changes to the exposure. I intend to produce another animated GIF from the LPI images, but that is going to take a while because I have to put everything through Registax and I do have a day job waiting for me!
Subject: Total Lunar Eclipse
Scope: 9 x 50 Finder/Guider
Filter: None
Mount: CG-5 (Synta motors, PicGoto Simplificado at Lunar rate)
Guiding: none
Camera: Meade DSI Ic
Acquisition: Nebulosity 3.2.1
Exposure: 0.001 s at about 20% gain up to 0.4 s at 100% gain, series over about 5 hours shot every 2 minutes
Stacking: none (single frames)
Processing: demosaic and square in Nebulosity. CS6 combine into animated GIF; add 1st frame caption. All frames except the first are 0.2 s.
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