FrankS
Registered User
Marko, the Summar is a collapsing lens. Mount it on your Bessa in extended mode, open the camera back, set the shutter to B and hold/lock it down. Watch through the camera back as you slowly collapse the lens to see if it hits any parts of the camera. If it does (and I think it will) you can put a spacer like a plastic washer over the lens's barrel to prevent it from collapsing all the way and hitting interior parts of the camera's shutter box.