Color Skopar 25mm

[jpa66]

Well, I'm on my second 25mm CV lens, and this one appears to have developed a spot. It wasn't there when I got it, but it seems to have appeared within probably two to three weeks of the time I received it. If anyone has any idea of what it may be, I'd greatly appreciate it.

The quality of CV lenses is really starting to get to me...

Oh, the spot near the middle of the lens is the one I'm talking about - it's not a reflection.

 

[Melvin]

Looks like it may be fungus. If it's on the outside it should come off with a Q-tip and lens cleaner. It has been so humid in Chicago (94% today!) this a danger. AC and exposure to light are good preventative measures.

 

[jpa66]

Unfortunately, it's on the inside. I'm not so sure about it being fungus - my house is relatively cool, I have a big A/C unit, and I keep the lens in my ( air-conditioned ) bedroom. None of my other lenses have ever had ( or have ) any problems, including another CV one. I'm far from an expert in these things, though.

And yes, it is humid here, but I lived in Pittsburgh most of my life, and this ain't so bad compared to the humidity there!

 

[aldenfender]

Is it under any warranty? Maybe you could ship it off. I live in Louisiana, and I have put my lenses through humidity hell... still they are all doing good, two of them are color skopars, and one zeiss 50mm. When I come inside I usualy clean them with a lens cloth. I'm not sure what else to do to prevent fungus. Let me know if you find anything out.

 

[pvdhaar]

If this developed in 2 or 3 weeks on a new lens, then that's remarkable. I would guess it takes more than a couple of weeks for fungus to get a foothold inside a new lens. That is, unless there has been some organic matter present. Are you sure it wasn't there when you got the lens and that you somehow missed it?

Another thought: could it be that the glue for cementing of two lenses into a group hasn't been applied uniformly enough and that there's a delamination spot?

 

[jpa66]

If this developed in 2 or 3 weeks on a new lens, then that's remarkable. I would guess it takes more than a couple of weeks for fungus to get a foothold inside a new lens. That is, unless there has been some organic matter present. Are you sure it wasn't there when you got the lens and that you somehow missed it?

Another thought: could it be that the glue for cementing of two lenses into a group hasn't been applied uniformly enough and that there's a delamination spot?

Yes, I find it hard to believe that it's fungus. It doesn't appear to be, and it does appear to be sandwiched between the two lenses. At first I thought that it might be condensation, but I really don't know much about that kind of thing - it was just a wild guess. Your second thought could be it, but once again, I really am in the dark in this area.

It is still under warranty, but I was informed that if the problem was with condensation, then it's not covered. I suppose I'll have to send it back, but that will have to wait, as I'm leaving town for a little while.

Thanks for the thoughts. Feel free to keep them coming.