Come to think of it, back in my large format camera days, we had light leak issues... if light was leaking into the bellows, we used gaffers tape. There was also a huge defect where under bright sunny conditions, looking in the rear of the camera, you could barely see the image let alone focus, we had to use a cloth! Can you believe that? a white and black cloth? and the manufacturer wouldn't even supply it, we had to buy our own!