(meteorobs) film any good for this year Perseids?

[Ed Majden]

on 8/10/04 11:20, Robert Lunsford at lunro.imo.usa at cox.net wrote:

> You can photograph even when the full moon is in the sky. You just need to
> make sure you are pointing away from the moon and adjust the length of
> exposure to avoid fogging the picture. This would range from one minute
> during a full moon up to fifteen minutes in a dark sky. The focal ratio of
> your lens and the sensitivity of the film also determine just who long you
> can keep the shutter open.
> 
> Clear Skies!
> 
> Robert  Lunsford
> 
    For the ones worried about film fogging why not add a chopping shutter
to your camera.  Not only will you be able to increase your exposure length
before fogging becomes a problem but you will also have the angular velocity
of the meteor provided your motor that drives the occulting disk runs at a
constant speed.  A synchronous motor on the North American grid will run at
a pretty constant speed.  I plan on using a 400 rpm Hurst Synch. Type CA
motor with a three blade occulting disk.  This will give me a 20X per second
chopping rate which is fine for fast meteors like the Perseids.

Ed Majden
AMS Spectroscopy
Courtenay, B.C. Canada.