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From: feikema@mmm.UUCP (John Feikema)
Newsgroups: net.rec.photo
Subject: Re: Tripods and Shutter Speeds
Message-ID: <401@mmm.UUCP>
Date: Tue, 14-Jan-86 09:37:38 EST
Article-I.D.: mmm.401
Posted: Tue Jan 14 09:37:38 1986
Date-Received: Fri, 17-Jan-86 01:15:32 EST
References: <24800003@gypsy.UUCP>
Reply-To: feikema@mmm.UUCP (John Feikema)
Organization: 3M Company, St. Paul, Minn.
Lines: 26
Summary: 

In article <24800003@gypsy.UUCP> tjo@gypsy.UUCP writes:
>
>A final question: With a leaf shutter, why isn't the center of the 
>negative overexposed, and the edges underexposed, since the shutter
>leaves the center of the negative open for a longer time than the 
>edges?

The shutter does NOT leave the center of the negative open for a lo9nger
time than the edges. Remember you have a lens! If the situation you describe
were a problem then when you stop down, i.e. reduce the diameter of the iris
opening only the center of your negative (slide) would be exposed. Clearly 
this is not true. Take a look at an elementary optics book for a good 
explanation of what is going on.

-- 

             John Feikema

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