Missing C-Mount Lens Bottom

[tommygdawg]

Hey all,

I've picked up this C-mount lens on ebay. It's missing the part of the lens that actually has the C-mount, which means I can't actually adapt it to anything. I've attached some photos for reference. It's like there's supposed to be a piece that screws on that actually has the C-mount. Any thoughts on how I can get this piece or put together a work around?

Thank you!

 

[David W. Jones]

Almost looks like an Arri mount.

 

[Ryan Patrick O'Hara]

Hey all,

I've picked up this C-mount lens on ebay. It's missing the part of the lens that actually has the C-mount, which means I can't actually adapt it to anything. I've attached some photos for reference. It's like there's supposed to be a piece that screws on that actually has the C-mount. Any thoughts on how I can get this piece or put together a work around?

Thank you!

I don't want to sound condescending but have you tried screwing into the C-mount? That looks very similar but maybe a little different... at first it's hard to tell from your pictures if that knub is threaded or not, but since you said "it's like there's supposed to be a piece that screws on that actually has the C-mount," I'm going to assume it is. The problem is that those threads (if there) seems to be smaller pitched or more numerous than most C-mount lens threads. It also looks a bit bigger but that could be an illusion from the photograph.

Although that looks like a C-mount in your picture, you might be missing an extra metalic threaded piece because if you take a look at three of my many C-mount lenses below. The only difference is in my photographs you can see the threads clearly because they have a different metallic finish and there's only about 3-4 screw threads. You might be missing that small piece if your lens does not go into C-mount naturally.

From looking at your photo, it's unclear to me if that's just normal C-mount or if you are missing a very small 'extra' piece that has threads, like the brass/silver threads on some of mine. That might be very possible as it appears if your lens is threaded, it would be a much smaller pitch than what appears on mine. Again it's hard to tell from the photo.

If your knub has screw threads on it, i'd suggest just trying to put it on a C-mount. Have you?