Comet Linear C/2000 WM1
Object: Comet Linear C/2000 WM1
Date: Nov 21, 2001
Exposure: 40 Minutes
Film: Kodak LE400
Equipment: Losmandy G-11 GEM, ETX90 piggybacked on 10" f/10 Meade OTA
Autoguider: SBIG ST-4 guiding on the Comet.
Camera: Nikon F
Hardware & Software: HP S20xi film scanner & Hamrick Vuescan 7.1.1. The scan was processed, and cropped, using Picture Window 3.0.

Info: Comet Linear C/2000 WM1 was photographed on November 21, 2001, The slow photographic speed of the ETX proved to be a challange for this shot. I'm also sure that the 4.5 mag skies this shot was taken from played a roll. You may notice that the stars are trailed in the image, this is because the autoguider was tracking the comet and it is quickly moving relative to the background stars. I used the 10" as my guide scope for the ST-4. Even with the 10" the ST-4 needed a 6 second exposure with the gain set to 3x in ccdtrack in order to track on the comet. Interestingly, at one point during a different exposure, a star entered the ST-4's guide box. When the star left the guide box, ccdtrack kept right on guiding on the comet. This resulted in ccdtrack averaging the positions of the star and the comet and all the star trails show a kink at that point.
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