VC 35/1.4 infinity adjustment

[ricardovaste]

Has anyone ever worked on a voigtlander 35mm 1.4 M mount lens before? Or a similar voigtlander lens?

It seems the infinity is off on mine and I wanted to adjust it. I'm very familiar with SLR lenses but wanted to see if anyone had any insight or knowledge they could share on this type of lens.

Thanks,
Richard

 

[rcubed]

Does it focus past infinity? My CV40 went past infinity so I had a shim made (from a old membership card ~0.7mm) that fit right behind the mount. This shifted the lens forward just enough for proper infinity focus.

 

[ricardovaste]

Does it focus past infinity? My CV40 went past infinity so I had a shim made (from a old membership card ~0.7mm) that fit right behind the mount. This shifted the lens forward just enough for proper infinity focus.

It does go beyond infinity. I actually hadn't thought of that. I can make such a thing myself as I have a small metalworking shop for hobby stuff.

Only I'd prefer not to go that route, as it would require so much trial and error to get it spot on at infinity.

Is this the only option? Is there no way to adjust the helicoid with this lens...?

edit: I should perhaps note that it seems more noticeable with my new Leica 240, rather than my old one (a different 240). Which one was more "accurate", I do not know, but I'd really rather not send the camera in to be calibrated to this lens as it would cost quite a lot, and then may not work well with other lenses.

 

[rcubed]

It does go beyond infinity. I actually hadn't thought of that. I can make such a thing myself as I have a small metalworking shop for hobby stuff.

Only I'd prefer not to go that route, as it would require so much trial and error to get it spot on at infinity.

Is this the only option? Is there no way to adjust the helicoid with this lens...?

edit: I should perhaps note that it seems more noticeable with my new Leica 240, rather than my old one (a different 240). Which one was more "accurate", I do not know, but I'd really rather not send the camera in to be calibrated to this lens as it would cost quite a lot, and then may not work well with other lenses.

I opened it up hoping it would be easy to adjust like the CV50 1.5 LTM, but its completely different. I didn't feel confident taking the lens completely apart so I just tried a shim first. I got lucky because it worked on the first try.

The lens has linear error so the lens will still focus correctly regardless of where the infinity stop was, it just bothered me that it went past. Lol

 

[Ronald M]

VC does not make lenses. CV or cosina voitlander does.

 

[Larry H-L]

You might try a thin piece of copper tape on the exterior surface of the helical, if there is room to fit it on, though I don't know if that is moving the focus patch in the correct direction.

 

[Larry H-L]

Here:
https://www.dpreview.com/forums/thread/3476995

Scroll down to Brian Sweeney's post and picture.

 

[mooge]

Infinity is off - on the image or in the rangefinder, or both?

 

[rcubed]

Infinity is off - on the image or in the rangefinder, or both?

For mine, the rangefinder was accurate, the image was accurate, but on the barrel, infinity focus was achieved before it hit the infinity hardstop.

 

[Beemermark]

For mine, the rangefinder was accurate, the image was accurate, but on the barrel, infinity focus was achieved before it hit the infinity hardstop.

Does it matter if the marking on the lens barrel isn't perfect? You start "adjusting" things and end up with the RF not giving correct focus. If you set the aperture @ 1.4 and set the lens marking to infinity (ignoring the RF); then focus on an object more than 30 feet away, is the negative out of focus? I doubt it.

My 2 cents.

 

[rcubed]

Does it matter if the marking on the lens barrel isn't perfect? You start "adjusting" things and end up with the RF not giving correct focus. If you set the aperture @ 1.4 and set the lens marking to infinity (ignoring the RF); then focus on an object more than 30 feet away, is the negative out of focus? I doubt it.

My 2 cents.

If I used the lens marking at infinity, it would not focus correctly. It goes "beyond" infinity. I would actually have to use to rangefinder to find where infinity was rather than just hitting the hardstop.

Since the lens' focusing is linear, adding a shim just moves the entire lens assembly forward enough for the infinity hardstop to couple correctly, thus giving proper infinity focus at the hardstop.