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RE: [APML] Q4 exposure times?



Ric,
 
You're 10.5 minute exposure is likely going to produce a trailed comet if you guide on a star.  Assuming your calculations are correct, the guiding tolerance for a 90 mm lens is approximately 57".  Without noticeable trailing in the comet, you could probably expose for 3.5 minutes; however, if you are guiding on the comet, the limit is your skies limiting magnitude at the time of the exposure.  Last, E200 is probably not the best film choice for comets since it is weak in the blue part of the spectrum.  Given Comet NEAT's distance from the Sun and its orientation to the Earth, it will primarily exhibit an ion tail which is blue.  You might be better served choosing Fuji Provia 400F.  It's expensive, but it should do a fantastic job recording the comet.
 
Wade
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