I've just bought a 250mm Sonnar C on ebay for my 500C/M and after trying it out for the first time this evening I noticed a black 'bar' at the top of the frame. I assumed there was something in front of the lens at first. The bar isn't visible with my 80mm. See attached images. (Apologies for the low quality).
The body was sent to Black on White in the UK for a repair a few months ago, after jamming.
Is the mirror out of place or is this something else?
250mm Sonnar C