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Re: [OM] even more about the F280

Subject: Re: [OM] even more about the F280
From: "Tom Trottier" <Tom@xxxxxxxxxxxxx>
Date: Tue, 23 Apr 2002 10:32:04 -0400
At http://www.rit.edu/~andpph/text-streak.html the fellow has  
measured the F280 operations. The flash duration only varies when the 
camera is set to manual exposure. On auto exposure, the duration is 
always ~1/25. This is close to the full time from 1st curtain open to 
2nd curtain close at 1/60.  The curtains take 1/80 (12.5ms) to go 
across the frame, so for 1/60th (16.666ms) exposure the shutter 
travel is 16.666 + 12.5  = 28.66 ms or 1/29 second. For 1/2000,  .5 + 
12.5  = 1/77. Of course, on auto, you don't know the final shutter 
speed when you start the exposure and you don't want to run out of 
light before you finish.

So the F280 will give more even exposures and use less energy on 
manual exposure using Super FP. But normal OTF will give twice the GN 
at 1/60. 

Since the Super FP GN is so low, it is really only useful for macro 
or low light situations with high speed film. Have others found it 
useful in other situations?

tOM
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