coding CV25

[johnalex141r]

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I've been having trouble coding a CV25. My other 3 CV lenses went ok, but this is one is giving me trouble. Anybody had success? Can someone send me a picture of the back of their coded lens??

 

The code that I have been trying is for the Elmarit 24mm f2.8.

 

Thanks; JohnS.

[Stan Raucher]

I've also had trouble hand coding my M-mount CV25 and CV40 lenses with a black sharpie using Bob Blakley's template. Any suggestions would be appreciated. BTW, I've converted the CV40 to bring up the 24/35mm frame lines by filing the lug.

 

Stan

[cme4brain]

I've been having trouble coding a CV25. My other 3 CV lenses went ok, but this is one is giving me trouble. Anybody had success? Can someone send me a picture of the back of their coded lens??

 

The code that I have been trying is for the Elmarit 24mm f2.8.

 

Thanks; JohnS.

 

I have had the same trouble, addressed in other threads. It seems that the lens flange has a screw head exactly where there needs to be a white coding mark. You need to use lots of white paint to fill in the screw head. I tried it but could not do it, but others have done so. I am reluctant to remove the CV25 lens flange myself and mail it to Jim Milch for milling- I am afraid I will do something wrong and the lens not work exactly correctly afterward- my personal caution. My CV25 is my only uncoded lens. I should try to fill in the screw head some more I guess.

[gesper]

I have the screw mount CV25 and used a Milich adapter coded with black nail polish (didn't bother with white). Worked the first time.

[johnalex141r]

Yeah, I've got 3 screw mount adapters that I added tabs to (old CV type 1s) and milled dimples, and put black paint in. All work wonderfully. I'm simply having trouble with the M mount CV25.

 

(I have a couple of lathes and a good milling machine (a british centec 2b one, with DRO, if anyone cares) and over 30 years putzing about with them, so the machining is not a problem)

 

As my CV25 is M mount; removing the adapter was easy, 4 screws, no loctite on them. I'm now having trouble coding it, maybe because where a screw is there is a white and black "dimple", and maybe my painting of the screw is not good enough?

 

I'm wondering if my dimples are *really* in the correct place, or whether I'm having trouble because of reflections off of the screw, or whether the code on Carsten's site is correct, or ... or ... I do not have any official leica lenses, nor Mr. Milich's adapters, to compare against.

 

Last night I changed the screw for a flat headded slot screw, put thicker white paint in; I'll see tonight if I can get it to be recognized as a 21mm (both dimples white where the screws are)

 

Thanks - JohnS.

[cme4brain]

Yeah, I've got 3 screw mount adapters that I added tabs to (old CV type 1s) and milled dimples, and put black paint in. All work wonderfully. I'm simply having trouble with the M mount CV25.

 

(I have a couple of lathes and a good milling machine (a british centec 2b one, with DRO, if anyone cares) and over 30 years putzing about with them, so the machining is not a problem)

 

As my CV25 is M mount; removing the adapter was easy, 4 screws, no loctite on them. I'm now having trouble coding it, maybe because where a screw is there is a white and black "dimple", and maybe my painting of the screw is not good enough?

 

I'm wondering if my dimples are *really* in the correct place, or whether I'm having trouble because of reflections off of the screw, or whether the code on Carsten's site is correct, or ... or ... I do not have any official leica lenses, nor Mr. Milich's adapters, to compare against.

 

Last night I changed the screw for a flat headded slot screw, put thicker white paint in; I'll see tonight if I can get it to be recognized as a 21mm (both dimples white where the screws are)

 

Thanks - JohnS.

 

 

I may try to take off my CV25mm "M" mount flange if I do not encounter loctite.

[sean_reid]

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The template is off a little bit. Compare it to a milled adapter to see how. Anything drawn or painted on the bayonet will rub off over time (some of it on the camera's 6-bit sensor itself). Having the bayonet milled is really the best way to go (he wrote with is reviewer hat off). My CV 21/4 is milled.

 

Cheers,

 

Sean

[etrigan63]

I had John Milich mill my CV 25p and it works just fine. You should only have to paint the screw white, the last coding pit falls just past it.

[johnalex141r]

I had John Milich mill my CV 25p and it works just fine. You should only have to paint the screw white, the last coding pit falls just past it.

 

Ah - maybe that's my problem. I have milled my pits inline, as the sensor is straight, anyway. On my jig, the last pit is a bit into the screw hole - and it has to be black. I'll take it off, and move the pit slightly to the right, and see what happens.

 

Funny that my other lenses were ok - maybe I did not set my jig up properly for this (my last) lens to code.

 

Thanks - JohnS.

[etrigan63]

Here is a close-up of the pits John milled for me. Hope this helps.

 

[johnalex141r]

Here is a close-up of the pits John milled for me. Hope this helps.

 

Yes, very much. It looks like my black dot on the right is slightly too far to the left; I have not needed to code lenses with any of the last 2 pits black. Really looking at my coding, it is that last bit that I'm having trouble with.

 

JohnS.

[etrigan63]

Glad I could help.