Telescope: Skywatcher 8" f/5 Newtonian
Focus: Prime focus
Camera: SAC7B, uncooled
Exposure: 77 x 25s
Date: 19th July 2003
Processing: The usual YRGB
processing, except that the subtraction of a 'banding flat' (see the
Advanced Processing page) was done to
remove fine banding noise. Noise reduction in SGBNR on the final
colour image. There was a slight brightness gradient from left to
right in the raw images, so subtraction of a synthetic sky background image
was done in Iris.
Sky conditions had been rotten for a month
and a half at the time this image was made. On this night conditions
started out at medium transparency and deteriorated after less than an hour.
I kept the telescope tracking this object for 3 hrs. Out of more than
400 frames taken, only 77 were usable. The new technique to remove fine banding was
very necessary here due to the low surface brightness of the object.
Luminance layering was done to increase