Re: Infrared-Digest V #123

[Gary Beasley <beasleyglb@xxxxxxxxxxxxxx>]

>From: Bertha Adamson <badamson@xxxxxxxxxxxxx>
>Subject: Shooting IR in Moonlight
>
>I've been wondering about using moonlight to take IR pictures.  I know
>moonlight is reflected sunlight, and that the moon itself is basically
>"sunny-16", but is the proportion of IR in this reflected light the same as
>under bright sun?
>
>I've checked the information I have but night IR photography generally refers
>to using artificial sources or using an IR emitting light source in the
dark. 
>Has anyone tried shooting under a full moon?  What did you discover? Are
there
>online sources or books with this type of info? I am prepared for
>astrophotography type exposure times, but I want to make sure it is even
worth
>the trouble.
>
>And if this subject has been beaten to death many times before, just say so
>and I will retire to my corner bowed but unbroken.  :-) Thanks.
>
>Bertha
>
Actually there may be very slightly more IR to visible due to re-emission
of shorter wavelengths but if my experience with visible light and pushed
film is any indicator you will have times ranging up to an hour and who
knows what the reciprocity failure for HIE is? If you experiment try using
a low contrast developer and pushing some. Maybe Tmax will do, maybe a
special developer like Acufine or Ethol if they are still around.
What you have to remember is that the moon is a very dark object
intrinsically, it just looks bright against the black sky. Therefore it is
not going to act like a very efficient reflector. If you want to get really
scientific you may try some astronomy newsgroups for leads in finding the
actual IR reflectivity.
Gary Beasley
http://beasleyglb.home.mindspring.com/

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