Hi, I just posted a CONTAX Carl Zeiss Vario-Sonnar 100-300mm F4.5-5.6 T* Lens for sale but noticed the back element looks a little different - not too clear. Is this lens haze or is it normal for a lens of this age? I barely used it and it’s been kept in ac + a case. So I’m not sure. Thanks for any help.
It's probably not an age-related thing. I have Contax and other lenses of the same vintage, and they can be (should be) clear. Some lenses have aging problems with organic adhesives between 'cemented' lens elements, but I don't think it's an issue with CZ Contax. Shouldn't be too hard to find out.
You can probably get a better diagnosis, if you stop the aperture down to f/8 or f/11, and look at it from both the front and from the rear.
Yeah, there is a cemented group in the rear that's prone to separation. About six or so years ago, when the lens was very popular, some members were using a repair service in Taiwan that cleaned and recemented the groups.
zlgragg wrote:
Hi, I just posted a CONTAX Carl Zeiss Vario-Sonnar 100-300mm F4.5-5.6 T* Lens for sale but noticed the back element looks a little different - not too clear. Is this lens haze or is it normal for a lens of this age? I barely used it and it’s been kept in ac + a case. So I’m not sure. Thanks for any help.
I agree with others that it's difficult to tell what might be going on from the photo.
As I also live in very humid Florida, even in ac (particularly with ac that is not correctly sized), if one does not keep track of humidity levels, there can still be humidity issues over time. If the lens has been stored in a closed case, that could potentially even be worse unless you keep and replenish something like silica gel desiccant packs in the case with the lens.
See those two dots? You can unscrew the rear element group and check the clarity with more certainty. If it doesn't look perfectly clear, it will likely need repair or re-cementing. Interestingly, some copies show this issue (actually quite a few), while others never do. I had a copy that was crystal clear in that group, but I ended up selling it.
