C/Y Zeiss 50mm 1.7 Back Focus

[photomat-]

Hi,

I have a C/Y Zeiss 50mm 1.7 that has a back focus issue. Wide open at closest focus, the shift is off by about 1cm which is nearly 0.4 of an inch. Can anyone recommend somewhere I can send the lens for a CLA/service to get this fixed as I am getting tired of missing shots and it's my favorite lens. Any idea of approximate cost?


Thanks in advance.

Matt.

 

[ic-racer]

Hi,

I have a C/Y Zeiss 50mm 1.7 that has a back focus issue. Wide open at closest focus, the shift is off by about 1cm which is nearly 0.4 of an inch. Can anyone recommend somewhere I can send the lens for a CLA/service to get this fixed as I am getting tired of missing shots and it's my favorite lens. Any idea of approximate cost?


Thanks in advance.

Matt.

I'm not sure I understand the issue.
Even if the infinity stop on the lens is off, it should focus fine at close range. When you snap a picture, does the focus jump to different setting?

 

[Rol_Lei Nut]

As above, could the issue be with the camera body?
Do other lenses focus properly?

P.S. Saying where you are could help if you want tips for repairpersons.
Otherwise, people will assume that you are from the Center Of The Universe and let other people from the Center Of The Universe answer you....

 

[Mustafa Umut Sarac]

I visited his webpage and He is from Las Vegas.

Umut

 

[photomat-]

Sorry, I thought my location was listed on the side. I am in Las Vegas.

The issue exists whether I use a Contax body or an adapter on an EOS body. And at different focusing distances. I have no issues with a Tokina 28mm or a Zeiss 28mm.

 

[Rol_Lei Nut]

Still don't understand: is the image in the viewfinder focused but the result unfocused? Or does the distance scale not correspond to reality?
In the latter case, unless you're scale-focusing, how does it ruin shots?

 

[TimVermont]

Call Focal Point in Colorado and see if they will work on it. He has the needed expertise to get it right. Plan on sending body _and_ lens. http://www.focalpointlens.com/fp_intro.html

 

[photomat-]

Still don't understand: is the image in the viewfinder focused but the result unfocused? Or does the distance scale not correspond to reality?
In the latter case, unless you're scale-focusing, how does it ruin shots?

The image focuses in the viewfinder but the result is the focus is behind the area I focused on. So if I focus on the 20cm mark on a tape measure, the resulting focus is at 21cm or so. I took a great portrait of my niece where I focused on her eyes, the result was the side of head was in focus.

 

[photomat-]

Call Focal Point in Colorado and see if they will work on it. He has the needed expertise to get it right. Plan on sending body _and_ lens. http://www.focalpointlens.com/fp_intro.html

Thanks for the link, I'll check them out.

 

[naaldvoerder]

If this happens in, for example a Canon 5D, with adapter, it most likely means that the focusing screen is not "justiert", not placed at the right hight. Canon apperently presumes, that people with a AF camera do not need a properly placed focusing screen. Canon sellls a set of 10 "shims" to do this yourself. If this happens in a Contax body you may want to check if the mirror has not slipped downward from its metal frame. Apperently after some 20 odd years, the glue that hold the mirror in place losens up and the mirror can slip down. I think this is a known problem in the RTS and RTS@ and maybe other bodies. In a proper SLR what you see on the focusing screen, is what you get on the filmplane, even if the lens does not focus on infinity.
If you need more info on the Canon shimming, give me a call, i did this procedure on my 5D..

Jaap Jan

P.S. I think the focusdepth in the 28mm lenses is not shallow enough to show up the problem.

 

[Rol_Lei Nut]

+1

Also think it's a mirror or screen position problem

 

[photomat-]

Focalpoint gave me a guesstimate of $125 plus return shipping. I am having a hard time thinking that it is a screen / mirror problem on both cameras I am using it on. I need to find another Contax body to test with. Mine is a 167MT btw.

Thanks.

 

[ic-racer]

Not sure how to adjust the mirror in the 167 but the Contax 139 adjusts like a Yashica FX3 and is shown here (posts 8 onward). (there was a url link here which no longer exists)

 

[ic-racer]

I am having a hard time thinking that it is a screen / mirror problem on both cameras I am using it on.

Most people would have a hard time thinking that the lens shifts focus during the exposure then shifts back when the mirror comes down. But maybe it is somehow that you are holding the camera causes it to do that.

 

[photomat-]

Most people would have a hard time thinking that the lens shifts focus during the exposure then shifts back when the mirror comes down.

How would that happen?

But maybe it is somehow that you are holding the camera causes it to do that.

Umm, no. It is a consistent occurrence. For further confirmation, I'll check with a tripod when I get a chance.