What exposure speed with ASA-400 film should I use to capture the September, 1996 lunar eclipse?

I have only photographed a lunar eclipse once, and I used ordinary Kodak color film with a rating of about 200 ASA. I seem to recall that with a standard 50mm lens, and a dark sky, I had to use an exposure of about 1 second, so I would guess that for ASA 400 film a 1/4 second exposure might be OK. But the image was quite inferior. Without a telephoto, the image of the moon was so small that I had to enlarge it quite a bit on printing in order to see anything, and the graininess of the result was pretty bad. You need to use a telephoto, for sure, to get a large enough image on the negative, and I would guess that you will need exposure speeds between 1/2 to 2 seconds. Your best bet is to look at old back issues of Sky and Telescope or Astronomy magazines which usually have many photographs taken by amateur photographers. The captions often give the lens/film/exposure information.


Copyright 1997 Dr. Sten Odenwald
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