Does anyone know if the OM-G/20 focusing screen is the same as the OM-40/PC? I've read that the OM-40 screen is the same as the 2-13, which is a brighter version of the 1-13 that is in my OM-4T. Was wondering if I need to specifically look for a broken OM-40 as a donor camera, or if it would be safe to widen my search to include OM-20s and OM-30s.

Secondly, I know OTF metering will not be affected. I also assume the spot meter will be unaffected, since the central spot of both screens should be identical. However, would I have to compensate when shooting manually but reading the meter in the viewfinder? Would guess the camera would tend to underexpose since the viewfinder will be brighter.

Lastly, is there any impact on focusing accuracy? From my experience, brighter mattes tend to show a larger DOF, making it more difficult to nail focus, but I'm hoping the difference is very slight between the 2-13 and 1-13 screens.

Thanks in advance for any help!

Ask John Hermanson, he is a member here and is a retired Olympus service manager. He still works on the OM system on his own, and is probably the most knowledgeable person in the USA on the OM system. His website is http://zuiko.com

Thanks. I've sent him an e-mail

i've had a few OM30/40's for donor cameras. But I have not found any difference in the focusing screens.