How infinite is infinity?

[Rob F.]

There is a stop in the chamber that limits the travel of the cam follower arm. On some M3's, it was set to limit the arm to 1 meter. Later, when the lenses came out that focused to .7M, the stop was factory set to allow this distance. The earlier ones can be re-set to 0.7M by bending the limit stop a bit. That in itself shouldn't change the infinity setting.

 

To change the infinity setting, with the lens off the camera, use an angled screwdriver to adjust the eccentric screw in the center of the cam follower. You can make an angled screwdriver out of any small screwdriver of appropriate size, if you have a file or a grinder. You can also flatten the edge of an angled X-Acto knife blade.

 

Make only a small change at a time in the position of the slotted adjuster. Put the lens on and note whether the infinity adjustment is now better, or worse than it was. If worse, remove the lens and tweak in the opposite direction. If better, then make additional adjustments until it's perfect.

 

Just a small pressure, rather than a deliberate movement of the cam screw, may be all that is required when you are close to being right on. You will get a lot of practice at lens removal and fitting.

 

Sorry I took so long to answer this--I lost track of the thread.

[maciek_eyman]

Thanks a lot, Rob. I'll give it a try. And actually you've answered my question within two hours of my posting it. Thanks again, Maciek