The diaphragm's diameter may not change, but the aperture value changes proportionally to the focal length - regardless of exposure mode.
Originally Posted by Razr
All that happens in M or Av mode is that the diaphragm's diameter may remain constant (or close to it for simplicity), the aperture value meanwhile must change as defined by mathematics.
Oh, did I mention you are an idiot?
Last edited by cwphoto; 10-25-2007 at 07:55 PM.
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