It's definitely not upside down (only one way to install it with the tab in the right position). How can I fool around with the mirror stop to determine if that's the problem? Thanks Les for the repair manual, seems like I can also change the focusing screen frame itself. It does seem like it's not that tight when clipped in, as there is still some vertical play as I can push the frame up further when it's clicked in. Unfortunately it doesn't give a good illustration on how to take it apart and adjust it.
Originally posted by asaru If the focusing screen is in alignment (yes, I know that's a big if) could it be that the cleaning has just made obvious the fact the photographer's vision needs optical correction?
Bad vision shouldn't affect the split image from lining up correctly if I'm not mistaken, although it is true if I had poor eyesight it would still look blurry to me. But I have contacts, and with them perfect vision so that's ruled out.