Originally Posted by Chriscrawfordphoto
I haven't used the OM-D EM5, so I can't comment on how it compares to the much newer Pen-F and E-M1 mk II viewfinders.
I don't think the electronic viewfinders are as clear and sharp as a good optical finder like that in the OM-1. For autofocus, they're fine, but for manual focus they're a bit of a pain.
Because its is near-impossible to judge sharpness on them when manually focusing, the Olympuses and many other mirrorless cameras offer a magnified mode on the EVF where it magnifies part of the image to facilitate manual focusing. Even with that, manual focus works best if you activate focus peaking (it can be turned on and off).
It works, but feels like a kludge. Also in very dim light, MF is hard. That's true also of many optical SLR finders, too, though.
So, my verdict is that the EVF in the newer Olympus cameras is ok. It takes some getting used to and if you only do AF, it works well. Its the price you pay for having such tiny, lightweight cameras.
I have been using my XT-2 with both adapted lenses and for slide copying with an enlarging lens (where focus is critical) and feel the same way. I am able to get it sharp, but really did not think about the fact that is actually an EVF. In general use the EVF is so good on the Fuji that I take it for granted, but in these cases, the optical reality of the EVF is important. These cases may may ones where DSLRs still have some advantage over mirrorless.