Nikon mount doesn't accept certain lenses

[Taylor Kokinos]

Long time reader, but this is the first time I've bothered to post. Anyway, I recently got an MX RED ONE, and to save cost and reuse my fairly nice collection of glass, the Nikon mount as well.

Most lenses work fine, but I've had problems getting a couple of older lenses to even mount. They will fit into the mount, but the little lever can't be turned to latch the lenses into place. One is an old-school 200mm prime, pre-AI, and the other is a 20-80mm zoom. All of my other lenses work fine. Same problem on both of these. Any ideas? The zoom is AI and other non-AI lenses work just fine on the RED. Both lenses mate with a D7000 just fine as well. Any ideas as to what could be causing this?

Also, I've noticed that G-type lenses without aperture rings remain stopped all the way down. This is expected with the RED mount, correct?

 

[Robert Hart]

The older lenses have an overhanging iris ring. The older Nikon camera F-mounts have a shoulder which is deeper rearward of the flange face by about 1mm and of a slightly narrower diameter which enables this overhang to clear. I think the Optitek guy who posts here may have a RED mount which accommodates the older lenses.

I understand there may be in production or in development, a Nikon F style mount which enables manual actuation of a mechanical iris coupling between the Nikon G lenses and the mount. I am not sure about that one. Again the Optitek representative or Red developers themselves may be able to advise.

 

[Abraham Lim]

I had this problem with a couple of my Nikon AI lenses. I bought my mount from Doug Underdahl, and he informed me that the mount can be adjusted to compensate.