At 20:32 20.10.99 -0500, W. J. Liles wrote:
>An f6 1200mm and an f7 2400mm lense! Big Glass! Probably not easily
>handholdable (is that really a word?).
>
>At the prime focus of mirrors that size a full moon might burn a hole
>through your film without a filter! You need to try them on nebulae or
>something like the Andromeda galaxy (M-31 I think)with a guided time
>exposure if they'll let you.
You could probably burn a whole in the film if all the light hitting the
mirror was focused in one point, but you're creating an image of an
extended object, and as the moon is lit by the sun photographing it at f/6
with a telescope is no different from photographing a house (or <insert
other object>) in bright sunlight at f/6.
Don't worry, although the moon seems very bright in the telescope when you
eyes have adapted to the dark it is perfectly safe to you and your
equipment. IF YOU PLAN TO PHOTOGRAPH THE SUN, THEN YOU'LL NEED A FILTER OR
ELSE YOUR FILM, CAMERA OR EYES WILL GET BURNED!
Regards,
Thomas Bryhn
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