Carl Zeiss Jena 50mm f2.8

Messages
1,620
Name
Stephen
Edit My Images
Yes
Quick question. What does the M and A switch/dial for at the side of the camera. Can't see that is anything to do with focus … but? Am I wrong?
 
"M" = manual aperture lock (you view at the selected aperture). "A" = automatic stop down (you view at the maximum aperture and the lens stops down as the shutter is released).
 
Looks as though the same thing has happened to my lens:

Found this on a Photo.net thread re: the MTL5 and its lens

Chris Dzombak , Aug 12, 2008; 10:44 p.m.

It turns out that the lens was stuck in 'manual' mode, meaning that the automatic step-down was disabled. The switch for M/A was stuck, so I figured that since it only cost $10 it couldn't hurt to take it apart. It wasn't too bad - I only took off the very back ring that mounts to the camera. I found that a small bearing which the switch relies upon had fallen out of place, so I replaced it and now the lens works almost perfectly. The diaphragm blades are still stick sometimes; I think there's a little oil on them.

The full thread is here
 
Yet another "old" lens purchased and this one has a MANUAL/AUTO switch on the barrel. The switch on this one "APPEARS" not to be working, just like the other I bought. Am I doing something wrong? Or is it an age thing and they become faulty?
 
Yet another "old" lens purchased and this one has a MANUAL/AUTO switch on the barrel. The switch on this one "APPEARS" not to be working, just like the other I bought. Am I doing something wrong? Or is it an age thing and they become faulty?
Is there a button on the face of the lens mount? What happens if you press it in while turning the aperture ring?
 
On the Helios lenses I've had, there is a little pin on the rear which is obviously depressed when it's mounted. They can be 'modified' for use on modern cameras.

The A/M though does relate to the aperture control.
 
Back
Top