Quote Originally Posted by HDNitehawk


If I am understanding you right. If I am in AV or TV mode and I set the exposure compensation a bit higher or lower, that it is adjusting the ISO settings to over expose or underexpose. For some reason I thought it was adjusting shutter speed. Since the change is displayed like the shutter.


That's not exactly what I meant -- I'll try to clarify [].


There is a difference between the ISO "setting" on the camera (and raw file) and the actual ISO of the JPEG after it has been through post production. When you set the camera to ISO 400 and Av 4.0, the exposure compensation will not change the ISO setting. But if you set EC to +2, then do -2 in DPP, the resulting file *will* have a different ISO than the one on the camera. See what I mean?



<meta content="text/html; charset=utf-8" http-equiv="content-type" />
Camera settings (ISO 100, Av 4.0, EC +0) + Post production settings (0 EC) = actual ISO of the JPEG file (ISO 100)


Camera settings (ISO 400, Av 4.0, EC +2) + Post production settings (-2 EC) = actual ISO of JPEG file (ISO 100)


In those two examples, the camera ISO settings were different (one was ISO 400), but the true ISO of the JPEG file is the same ISO 100 for both.


As another example, ISO 1600 with +2 EC has *less* noise than ISO 800 with 0 EC, when both are printed at the same brightness. But that's because using ISO 1600 with +2 EC results in an exposure index that is actually ISO 400.


Hope that helps,