Daniel Jewesbury

Thank you firstly for getting back to me, and so quickly - I appreciate it, and will leave the fastening ring well alone! But can I ask what you mean by ‘not fully up’? Daniel

I am using a Pan-Cinor 17-85 on my Bolex H16M, the lens with the dog-leg viewfinder. Something very strange has happened. The thread on the rear - the C-mount that screws to the camera body - has somehow become misaligned. The lens can no longer line up so that the viewfinder tube sits on top of the right-hand motor side of the camera - it’s now about 90° off and sits out to the side of the magazine. I don’t understand. I have taken a look at the thread (I tried unmounting and mounting it several times to convince myself I’m not going mad) and I note that the threaded barrel has two small notches diametrically opposite one another at the end; so I guess a pair of engineering pliers with an adjustable width could be used to rotate the thread barrel in the lens housing. But how has the thread become misaligned in the first place? And will it mess up the lens collimation? I’m filming in a remote location without engineering pliers and with a lot of rolls of film I need to shoot in the next 10 days! The fact that the lens is now 90° turned means also that the viewfinder frame is no longer straight: but when one unscrews the viewfinder tube, at the end of the part that it screws into, is another thread with diametrically opposed notches and these can be adjusted by hand to line the frame up again. Hence my wondering whether the notches in the lens mount itself have the same purpose. Can anyone help? Have you ever heard of this or similar problems?

Hi there - fascinating thread. But this link seems to be dead. Any way it could be restored..? I was searching for information on these topics just two years ago (I use an H-16 non-reflex with a Switar zoom, and wanted to get some other lenses) and information like this just didn’t seem to exist online. Thank you!