wobbly CV 35/2.5 PII - bug or feature?

[joeswe]

Hi,

today, trying to mount my newly purchased bayonet mount lens shade on my CV 35 PII, I noticed that the whole lens/aperture assembly sits somewhat loosely inside the barrel. When I grab the bayonet mount/aperture ring part and rotate it, I can move the whole lens assembly quite a bit (about one mm, I guess?) against the barrel. I assume this kind of "free play" is not normal and the lens has to be serviced? Has anybody experienced this and knows a quick fix? If it was just a question of tightening one of the retaining rings, I would try to fix it myself, but I don't have a lens spanner and don't want to purchase one just to find out that it won't do the trick.

thanks,
John

 

[Turtle]

its not a feature one mine. I'd return it.

 

[joeswe]

its not a feature one mine. I'd return it.

Well, unfortunately that's not an option. The lens shade was purchased recently, but the lens was bought used about half a year ago, so I would have to pay for the repair. I never noticed that wobble before (but I must admit I didn't inspect the lens too close either). It's just that I mounted the bayonet mount shade for the first time today (which needs a tiny bit of force, because it's quite a tight fit) and this is when I first noticed the wobble.

John

 

[haempe]

It is not unusual that CV (and Zeiss) lenses develop a slight wobble over the time. I own 6 CV lenses, of which 4 wobbling.
I know, it is irritating, but I never noticed any difference in the results. If you noticed something, time for repair, if not ... live with it... or not ... your free decision. 😉

 

[ferider]

For the Color Skopar PII the wobble is easily fixed. Just tighten the span ring in the back. You can do this with a small flat screw driver, but be careful not to slip.

 

[Chris101]

Just be glad it's not the f/1.7 lens. The screws hold it tight loosen easily, and are three layers in.

 

[joeswe]

For the Color Skopar PII the wobble is easily fixed. Just tighten the span ring in the back. You can do this with a small flat screw driver, but be careful not to slip.

Me again. I finally solved the problem. It was not the retaining ring in the back of the lens but some screws inside of the lens that had come loose. Actually one had already fallen out of it's threads. Whoever tightened them in the first place must have been in a hurry. The whole procedure is not a big deal and straightforward if you have the appropriate tools (it was the first time I disassembled a lens, actually), so if anyone should be confronted with the same problem, here is the fix:

tools needed:
Philips head screw driver #PH00, flat screw driver 2.5mm and a small/medium size lens spanner for the retaining ring

procedure:
Remove the outermost retaining ring in the back of the lens by turning ccw with a suitable lens spanner. Don't loosen any of the inner retaining rings, they keep the lens assembly together. The correct ring is marked by the red arrow in the following pic


L1120693 von eames68 auf Flickr

The focus mount can now be lifted off from the lens assembly. Turn the focus mount around and you will see a number of philips head screws. In my case some of the screws were loose in the threads, one had fallen out. Retighten the screws with an appropriate Philips head screwdriver (#PH00).


L1120689 von eames68 auf Flickr

Assembly is reversal of the above steps. Reseat the focus mount on the lens assembly. There is a finger on the base of the lens assembly (see photo) that has to be fitted in the appropriate notch in the focus mount, but that is more or less self-explaining when you have the parts in front of you. Tighten the retaining ring in the back of the lens.


L1120690 von eames68 auf Flickr


Happy shooting!

 

[agoglanian]

I appreciate the detailed post, I'm going to have to do this with mine as well as it seems a bit loose now also. Only issue is I don't have a spanner wrench... May have to figure something else out. Lens still works fine though. Thankfully!

 

[jarski]

thanks for sharing!