Tumbles
Member
I've been looking into getting a helios 44 lens. I'm after one of the earlier models that has 13 aperture blades, and I keep finding versions that have this odd mechanism off to the side. There's many listing that have this feature, but no one describes what it is. I can't find any articles describing it. Does anyone know what this is? I don't want to buy one and find out that it causes some sort of incompatibility with my camera.