Do not use the doubler.
I assume that you do not have a tracking telescope mount.
For a relatively light total lunar eclipse at totality, on ISO 100 film, you
need to expose for about 120 seconds at f/16. However, at 1000mm the maximum
length of the exposure that you can take without tracking is only about 0.5
seconds. Longer than that makes the image blurred. A 120 second image would be
hopelessly blurred.
If you shoot 500mm f/8 untracked, then your exposure (at totality) should be
about 1 second on ISO 1600 film, and it will not be blurry.
If it were clear in New England tonight, I would be using my 875mm F7 telescope
on a tracking mount with ISO 200 film for 6 seconds.
It turns out that a d*g*t*l camera looking into the eyepiece of a tracking
telescope is a very good method for lunar eclipses, because you can use shorter
exposures.
Matt
At 15:33 15-05-03 -0400, lostkase@xxxxxxxxxxxxx wrote:
> I think I sent my first question to the wrong location. Anyone have any
> suggestions for capturing the eclipse tonight in North America? I'm thinking
> OM-4T, 800asa film, Tokina 500mm reflex with doubler on Bogen tripod. Any
> hints, tips, suggestions ? Besides hoping for clear sky :)
--
Matt BenDaniel
matt@xxxxxxxxxxxx
http://starmatt.com
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