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12/18/04 M1 The Crab Nebula

The Crab is a super nova remnant from a star that exploded in the year 1054. Observers across the Earth saw it appear in the night sky as a very bright "new" star. Chinese astromomers refered to it as a "guest" star. It's shell of gas has been expanding the 1000 years since then to produce the beautiful nebula we can see today. I always seem to struggle with a lack of signal in the blue channel, the ST8/8i cameras are not very blue sensitive and when taking color shots, the blue is last in the sequence - Lum, Red, Green and last Blue. This often has the blue channel being taken when the object has passed the meridian and is lower in the sky, with more atmosphere in the way. This time I took the blue first, exposing the blue channel when the subject was still high in the sky. I also took a lot of it, as much blue as lum. All channels were taken with 5 minute sub-exposures and I can see a some tracking error in the stars. The data for this shot was easier to work with and I think the special treatment for the blue channel has paid off.