Voigtlander 50 Apo-Lanthar RF focus weirdness out of box

[FrozenInTime]

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I had a strange out of box experience with the Voigtlander 50mm Apo-Lanthar :

The focus cam would decouple from the rangefinder at 1.2m ; the lens was clearly focusing in live-view ; 1.2m - infinity seemed to focus accurately with the M10M rangefinder.

I sent the lens back and received a replacement today.

The replacement had the same issue 😞

I then spent much time swapping the 50mm lens between a M10M and M10  - both showed the same decoupling at 1.2m . 

The lens was fully clicked into the bayonet.  I could see no mechanical interference that would explain what was occurring.

None of my other lenses, many I used for a long time showed the same effect. I checked with a few at hand lenses , the 40mm 1.2 , 35mm Summilux ASPH and the similar 35mm Apo-Lanthar - all worked perfectly.

I then pulled out a M-A , wondering if the small box at the side of the roller arm on the M10 than is not present on the M-A was the cause. I found that camera's rangefinder focused correctly down to 0.7m with the Apo-Lanthar 50mm lens !

Moving the 50mm lens back to the M10 then M10M and the focus was now tracking from 0.7m to infinity 🙂  Very strange.

The only explanation I can reach is that that some inner mechanism associated with the floating element was sticking and not pushing the main rear cam ; the exercise I gave the lens was enough to get things moving correctly.

Hopefully the lens would be good from now on, but I'm going to be a bit ill at ease for a while.

Has anyone experienced similar ?

 

 

[TM1ka]

I had another problem with the VM 50 APO

I gave mine back because of CA branches tree in the backlight,

The picture was only pink, not possible to edit in LR 6. The jar was sent to Japan for examination. I then got the money back on the merchant's goodwill.

could of course also have been a coincidence

[FrozenInTime]

On 7/23/2021 at 12:29 PM, TM1ka said:

I had another problem with the VM 50 APO

I gave mine back because of CA branches tree in the backlight,

The picture was only pink, not possible to edit in LR 6. The jar was sent to Japan for examination. I then got the money back on the merchant's goodwill.

could of course also have been a coincidence

Thanks - I was on the lookout for that.

Fortunately,  the lens seems now to be focusing well and is free of any fringing CA on bright chrome ; even the bright sparking highlights on water seen looking into the sun are pure white 🙂