Zeiss Plannar zm 50 Focus might be off?

[kknox]

Hi I just received a Zeiss Zm Planar 50 I bought on ebay. The lens looks like its had no wear at all, looks new. The infinity focus is off from my Summicron 50' s. If you focus all the way out it goes past infinity & over focus I mean then the trees for example will not be in focus. Also if I focus like at 8 feet my other lens are at like 10ft. Is the focus scale ring just off and is this a problem? I used my M3 for the test. I have not had a chance to shoot any film with it. Please let me know if this is no big deal or if you have had the same problem. Thank's

 

[Maxapple88]

Maybe its a camera - lens specific issue. I found that newer and older lenses don't necessarily match up to infinity on the same body.

 

[awilder]

This sounds typical for Zeiss ZM. My 50/1.5 Sonnar did the same thing and it was new out of the box. Even various generations of Summicrons don't always agree. I found that the 50 Rigid, DR and black Wetzlar versions all pretty much agreed and focused perfectly at infinity while the "tabbed" Summicrons tended to slightly fall short of perfect infinity focus and the latest Summicrons vary from perfect infinity focus to slightly passing infinity at their endpoint. My sugestion is to send it to a reliable tech like DAG to check and adjust as needed. Unfortunately, Don is always swamped and expect turnaround to be at least 3-4 months. Sherry Krauter is much faster but you'll have to call her to see if she'll work on non-Leica lenses. I'm not sure she does. You might want to first take some pictures using fine grain negative film to check sharpness at "infinity focus" with the lens and compare it to the same setup with the lens at the infinity endpoint.

 

[kknox]

Thank's one more thing, do you think it will focus fine all the way up to infinity?

 

[awilder]

More than likely, the distance scale is more accurate than the way the lens' rf cam syncs to your camera so endpoint focus at infinity on the focus ring is accurate for true infinity distance. You can confirm this to be true or false by taking some pictures as descibed in my previous response.