RE: [APML] Film Choice for Total Lunar Eclipse (warning! OT)

["Thomas W. Earle" <twade@bmi.net>]

Stuart,

You should have no problems exposing at ASA 1600.  Do you have a
drive that compensates for the rotation of the Earth.  Better yet,
if you have a Lunar rate, use it.

If you have no clock drive, here are the longest exposures you can
take according the Michael Covington:

	350-700 mm		2 seconds
	700-1500 mm		1 second
	1500-3000 mm	1/2 second

For critical work (i.e. no blur), divide these times in half.

I'm not sure what f-ratio you'll be using; however, at f/5.6 a
relatively light total eclipse, is around 1/2 second at ASA 1600.
For a dark eclipse, you're talking 9 seconds.  The cool thing about
using a digital camera is you can experiment with your exposure
times on the fly. This allows you to find the perfect exposure.  We
who use film, have to hope and pray.:)

Good luck,

Wade


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