L. M. Tu
Established
The NEX adapters for some lenses have a ring that controls the aperture. Well....that's how it works with a Nikon G lens, even though there is no indication what the F-stop may be; with a Canon FD lens, one can turn the ring to the Lock position and then the aperture is selected on the lens itself. My question is, are there adapters that can lock that Open/Lock ring in place? That is the one feature that I wish I had on the Rainbowimaging adapters. Oh yeah, I acquired a new, used NEX-5 recently, and it's been great fun. 
Bugleone
Established
On my FD adaptor, the aperture ring controls the iris internally as in a Canon FD camera. One way the ring opens the aperture to the max of that particular lens,....other way it closes to the aperture set on the lens aperture control....ie, the 'auto iris' mechanism becomes manual and controled by the ring on the adaptor. There is no need to be able to "lock" the control as teh iris in FD lenses ar enot loose unless in a defective condition.
L. M. Tu
Established
Bugleone, that's not what I'm talking about. I wish to be able to lock the Open/Lock ring at any particular position, because, in the case of lenses without aperture rings, it controls the aperture (obviously), and I would like to lock it into one position and forget about it. Even in the case of FD lenses, where I simply set it to Lock and then set the aperture on the lens itself, I would like it not to move from the Lock position.