Thanks for your reply. From what I could tell yesterday, there is no pinhole or damage to either the shutter or aperture blades.
I have concluded that it is related to the glass lens somehow. Not sure how much energy I want to spend on this, but it would be cool to get it fully working again. I love the pictures I get with it.
it might be as easy as making / using a cheap lens shade ?
half frames are fun, aren't they ?