Focusing Issue with My New VC 50 f/1.5 Nokton (Nikon RF Mount)

[RanceEric]

I JUST opened my Nokton and attempted to mount in my SP.. It mounts, but will not couple with rangefinder.. So I try the S3.. Same problem, So I attempt the SP again. With some maneuvering, the lens clicks into the helical around 4.5m (on the barrel) but the body is still at infinity.. The same thing happens on my S3 and my partners S2. Has anyone experienced this problem? And is it something I can adjust/fix myself? Or will I have to send it out to be serviced? I was really looking forward to using this lens!

Thanks,
Rance

 

[alfredian]

Infinity squared

Infinity squared

Hi - I love this lens on both S2 & S3 bodies. I have two copies of the lens and several bodies. Once in awhile you get a body (=external bayonet) that is balky at taking any external lens. Otherwise, if you can actually mount the lens you should be okay.

Did you set both lens & body at Infinity? I forgot to do this once and could only close-focus. At least I was on the "good" side of the cam/hookup - my surmise is that if you get it misaligned the other way you can actually get the lens stranded and need to hack it off. So I've heard.

Short answer, for all my combos lens/camera with this lens, Infinity X Infinity works every time.

 

[jonmanjiro]

Rance, on the back of the lens around the rear element there is a spring-loaded movable metal sleeve. Does that metal sleeve move easily?

When you mount the lens on the camera, that metal sleeve fits into the mount on the camera side for rangefinder coupling.

It sounds like the metal sleeve is binding for some reason and not going all the way into the mount.

Compare that metal sleeve on the Nokton to the metal sleeves on your other external mount lenses. It could be that the corners need 'rounding' slightly.

 

[jonmanjiro]

Once in awhile you get a body (=external bayonet) that is balky at taking any external lens.

Nikon didn't get the mount quite right on the initial batch of S3 2000 cameras, so some external mount lenses couldn't be mounted on them. I've never had any trouble with the mount on a vintage Nikon RF though. My guess is that the lens is the problem in Rance's case.

 

[RanceEric]

Rance, on the back of the lens around the rear element there is a spring-loaded movable metal sleeve. Does that metal sleeve move easily?

When you mount the lens on the camera, that metal sleeve fits into the mount on the camera side for rangefinder coupling.

It sounds like the metal sleeve is binding for some reason and not going all the way into the mount.

Compare that metal sleeve on the Nokton to the metal sleeves on your other external mount lenses. It could be that the corners need 'rounding' slightly.

Jon, the element you're talking about rotates with the barrel and slides in the barrel easily. I see what you mean.. Is that something I can do? Is it possible to remove that element myself? Or is that something I should just send it out to have a repairman take care of?

 

[RanceEric]

Nikon didn't get the mount quite right on the initial batch of S3 2000 cameras, so some external mount lenses couldn't be mounted on them. I've never had any trouble with the mount on a vintage Nikon RF though. My guess is that the lens is the problem in Rance's case.

Yes, it's definitely the lens, not the bodies. This isn't a problem I have had with any other lenses.

 

[jonmanjiro]

Jon, the element you're talking about rotates with the barrel and slides in the barrel easily. I see what you mean.. Is that something I can do? Is it possible to remove that element myself? Or is that something I should just send it out to have a repairman take care of?

If the problem is what I think it is, you should be able to fix it yourself Rance. I'll try and dig up some photos to help describe what I think the problem could be. Watch this space!

 

[RanceEric]

If the problem is what I think it is, you should be able to fix it yourself Rance. I'll try and dig up some photos to help describe what I think the problem could be. Watch this space!

Thanks for your help!!

 

[jonmanjiro]

I found this pic on CameraQuest. There are three tabs that protrude from the spring loaded sleeve around the outside of the rear of the lens. These tabs slot into the mount on the camera. Check the corners of these three tabs to see if they're smooth. There should be no protrusions. If the corner is too 'sharp', or there is a protrusion, the sleeve might catch on the mount and not slot into position correctly. The first thing I'd try is to ever so slightly 'round' the corners on these tabs.

 

[RanceEric]

I found this pic on CameraQuest. There are three tabs that protrude from the spring loaded sleeve around the outside of the rear of the lens. These tabs slot into the mount on the camera. Check the corners of these three tabs to see if they're smooth. There should be no protrusions. If the corner is too 'sharp', or there is a protrusion, the sleeve might catch on the mount and not slot into position correctly. The first thing I'd try is to ever so slightly 'round' the corners on these tabs.

That's definitely not what the rear element looks like on my Nokton.. the metal sleeve on mine looks similar to the sleeve on the 35 f/1.8

 

[jonmanjiro]

This is the CV S-mount 85/3.5. I couldn't find a photo of the Nokton 50/1.5.

My point is that all external mount lenses have a similar sleeve with the three protruding tabs, and the corners of the three tabs have to be smooth. If they're not smooth, you'll need to file them down a bit.

 

[RanceEric]

This is the CV S-mount 85/3.5. I couldn't find a photo of the Nokton 50/1.5.

The point is that all external mount lenses have a similar sleeve with the three protruding tabs.

Ahh, ok. Well, they all seem smooth. There is some chrome showing on the corners, as if someone already tried to do what you're say already..

 

[jonmanjiro]

Ahh, ok. Well, they all seem smooth. There is some chrome showing on the corners, as if someone already tried to do what you're say already..

The chrome could be from your camera mount.

My guess is the tabs are slightly too wide. Can you measure them with a micrometer and compare with one of your Nikkors?

 

[RanceEric]

This is the CV S-mount 85/3.5. I couldn't find a photo of the Nokton 50/1.5.

My point is that all external mount lenses have a similar sleeve with the three protruding tabs, and the corners of the three tabs have to be smooth. If they're not smooth, you'll need to file them down a bit.

 

[jonmanjiro]

Ah ok. That sleeve is definitely the problem. It's not quite the correct size for the vintage Nikons. One or more of the tabs could be a fraction too wide, or the sleeve itself could be a fraction too thick.

Looks like you need to remove the sleeve from the lens, and work out what needs to be filed off by inserting the sleeve only into the lens mount.

 

[jonmanjiro]

There is some chrome showing on the corners, as if someone already tried to do what you're say already..

This could have been caused by trying to mount the lens on your cameras.

 

[RanceEric]

Ah ok. That sleeve is definitely the problem. It's not quite the correct size for the vintage Nikons. One or more of the tabs could be a fraction too wide, or the sleeve itself could be a fraction too thick.

Looks like you need to remove the sleeve from the lens, and work out what needs to be filed off by inserting the sleeve only into the lens mount.

I attempted to mount it on the Bessa R2S and had the same problem..

How do I remove it?

 

[jonmanjiro]

Can you post a photo of the lens rear element?

 

[RanceEric]

Can you post a photo of the lens rear element?

http://www.flickr.com/photos/ranceeric/sets/72157628145466914/

 

[jonmanjiro]

Ok, to get the sleeve off I think you first need to remove the outer retainer ring on the back of the lens. If you don't have any lens repair tools, the best bet is to buy a cheap pinset from a dollar store and modify it to fit the retainer ring. The retainer ring should come undone easily if force is applied equally to both slots.

Next, there is also a screw protruding from a hole on the side of the metal sleeve you need to remove. You need to remove that screw as well. Its a bit tricky to put the screw back in, so take notes on the position of the screw, the spring coils, the lens barrel position etc. before taking the screw out.

Once you've removed that screw, the sleeve should slide right off. Good luck!