----- Original Message ----- From: "J. C. O'Connell"
Subject: RE: A Question About Macro Lenses
At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work...
Your question applies to when ttl flash control is not available, such as when using studio strobes.
Since all my cameras have a built in meter, I use the continuous light meter to render an accurate assessment of the required exposure compensation by measuring how many stops of light I lose when extending the lens from infinity to the focus point.
William Robb
