For everyone of my individual lens I need to understand how its aperture will affect my different metering modes thru many trial and error shots. This is a major disadvantage using non-Canon mount lenses. To me is like shooting film in the good old days. When I decide to shoot at a specific aperture, using center spot or partial metering, I will test the metering at different tones/colors/shades and highlight of my subject/s and dial in the compensation, take a couple of shorts and choose the best. Evaluative metering will be less accurate and I will use it only for general landscapes. For this reason and also owing to age and degradation of my poor eyesight, I have decided to move to Pentax. I will be selling off my entire collection of OM lenses plus my 5D.
Sad to see you go Anthony, you have greatly contributed to thread with your wealth of information. I will try to add some into the thread as well...Been giving the OM Zuiko 135mm f2.8 a test run for the past 2 days.