> >"BUT, in MANUAL mode, the EV is separate. What is it that >the EV does when not changing shutter speed or aperture? >Computer wizardry and magic? Does it add more noise?" > >So, then in this case is the exposure compensation different >than EV? > >Thanks again. >Dave
EV ( exposure value) is a number which is determined by light intensity as measured by a light meter and the ISO value of either the film being used or the set sensitivity of the digital camera. It is just a number and it cannot change.
Now that we have this number, whatever it is, it defines the exact aperture opening and shutter speed which will properly expose the photo. This number can be maintained over many combinations of aperture and shutter speed and give the exact same exposure. When you are in Aperture Priority mode or Shutter priority mode the only thing the camera is doing is giving you a choice of which combination to use. The EV is still the same number.
Now if you want to make your photo lighter or darker what you need to do is compensate the exposure by using the EC button and dial in the + or - compensation you want.
You did not change the EV, that is controlled by the light intensity and ISO rating. You over rode the EV value. In effect you are disregarding what the light meter is telling you for whatever reason.