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Photography Question 
moore White

Flash - Diffuser

I have a Canon Digital Rebel with a 420 EX flash. Using a diffuser, I find I have to open up at least two stops and use an ISO of at least 200. Is this normal? Thanks for your insight.

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7/12/2007 4:44:58 AM

Bob Fately   Yes, Moore, this is to be expected, since the diffuser, by design, is spreading the light output of the flash tube to a greater degree. The tube produces a certain amount of light; if you diffuse, or spread, that light out, then it's like "diluting" the strength. You must compensate for this by opening the lens, etc.

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7/12/2007 12:26:49 PM

John H. Siskin
BetterPhoto Member
John's Photo Courses:
4-Week Short Course: An Introduction to Photographic Lighting
  Hi Moore,
Anytime you bounce your strobe off a wall, ceiling or umbrella you lose light. And you spread the light you have over a larger area. If you spread your light through a diffuser, you lose light. This is why more powerful light sources are so useful: you can get a lot of light and it will be diffused. Thanks, John Siskin

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7/12/2007 7:01:38 PM

Thomas Ehlers
BetterPhoto Member Since: 8/20/2002
  Wedding day
Wedding day
I used a strob above camera and controlled it with aperture. the background or ambient light was controlled by speed.
© Thomas Ehlers
Sony Cyber-shot DS...
ambient light is controlled by speed, strobes are controlled by aperture.

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7/17/2007 8:10:27 PM

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