I'm a bit late - but I've spent the last 12 hours at work, sooo... here goes: In situations when I believe the camera won't give me the exposure I want in aperture priority or shutter priority - I change metering mode to partial (not evaluating nor center weighed evaluating) - this gives the "narrowest field of view" metering the 20D is capable of. (A graphic representation of the area that is used in metering in this mode can be found in the user manual). Point to a part of your intended compo that should end up as the famed 18% gray (or medium toned blue, green, yellow,...whatever) - since the 20D have no true spot metering mode you may have to zoom in on you subject to get at a narrow field of "medium gray" - do an exposure reading, switch to manual mode and dial in the values you have just measured - surprisingly often you will get what you are after (some time to "learn" what is fitting to use as medium gray might be required). I suppose this sounds like a lot more work than your old camera... but once you get in the habit of doing this, it doesn't take long at all.... If you often shoot subjects with intended medium tones that are in too small areas to be measured by the inbuilt meter I can see no alternative but to get a handheld meter. Then you will get true spot metering with an angle of view somewhere near 1 degree (you might in fact find it easier and faster to use a handheld meter no matter if it's strictly necessary or not). Apart from the practical details I would strongly recommend that you buy a good book on exposure (for all I know you might allready know a LOT about it - if you do, disregard this suggestion:) Something like "The Perfect Exposure" by Jim Zuckerman comes highly recommended by me - for whatever that's worth:)