Is this Fungus ? I can´t identify, need help

[maxi0909]

Hello guys, I have this lens and it has a strange appearing only at the edge of the front glass element. the problem is that it is inside two canada balsam cemented lens pieces. So I couldn´t take it apart to clean it.
I just wanna know what this is and how I can remove it ( if needed or if possible )

When I saw fungus it was all around over lens element but in this case it´s only at the edges and look like snowflakes...

thanks

211620

[Tin Can]

Not on glass

Black paint failure
Usually a German lens

Don’t worry

[pgk]

Looks more like slight edge separation to me. I have a lens with 'Schneideritis' which doesn't look the same as this and is fundamentally cosmetic.

[maxi0909]

Not on glass

Black paint failure
Usually a German lens

Don’t worry


Oh that would be so "nice" :)

Yes it is actually a german lens. A Hugo Meyer Görlitz Doppel Plasmat. So you really don´t believe it´s some sort of fungus?

My biggest anxiety was, that it would spread out or go on other lenses.

[Havoc]

Looks more like slight edge separation to me. I have a lens with 'Schneideritis' which doesn't look the same as this and is fundamentally cosmetic.

That was my impression as well: beginning separation.

[Larry H-L]

Possibly the beginning of separation, but it looks drippy to me. Could it have been caused by a too wet lens cleaning attempt that caused seepage around the glass? Then it dried and residue remains visible.

[Tin Can]

I first looked on iPhone and image was too small

Now on big monitor

not Schneideritis

It always helps to give more info in the first post than later

Good fortune to you

[maxi0909]

Possibly the beginning of separation, but it looks drippy to me. Could it have been caused by a too wet lens cleaning attempt that caused seepage around the glass? Then it dried and residue remains visible.

Maybe. What do you exactly mean by "beginning" seperation? Could it be more worse in the end?
I don´t know anything about seperation at this moment. Is it fixable, will it progress?

[Steven Tribe]

It is patchy breakdown of the glue layer (canada balsam or early synthetics) which gives a Cloudy appearance due to separation of a solid layer on the surfaces of the two lenses. Could be due to drying out at sections of the very edge or some kind of oxidation process- again at the very edge. It grows inwards, like a bacterial growth or crystallisation! It will be a very gradual change ( over decades) and will probably be dependent on storage temperature.

[maxi0909]

It is patchy breakdown of the glue layer (canada balsam or early synthetics) which gives a Cloudy appearance due to separation of a solid layer on the surfaces of the two lenses. Could be due to drying out at sections of the very edge or some kind of oxidation process- again at the very edge. It grows inwards, like a bacterial growth or crystallisation! It will be a very gradual change ( over decades) and will probably be dependent on storage temperature.

Will Re-Glueing solve this problem? I mean if I seperate, clean and re glue them with canada balsam. Or will it happen after that again?

[Kevin Crisp]

Yes, regluing will solve it, but something this minor doesn't qualify as a practical problem. It may remain steady like this for years. I'd be especially careful to avoid temperature shocks, though, like leaving the camera bag in a car trunk.

This doesn't look like a balsam separation. I doubt even wide open something this minor would have an effect. I have a few Protars I have not fixed yet, and ring of crystallized brown balsam extends a couple cm into the lens. Stopped down, the lenses work fine. Compared to that, this is nothing. You'd be going to a lot of trouble to fix something that is merely cosmetic, but if that is very important to you, it can be fixed. Getting a lens like this apart, glued with what I assume is an older synthetic glue, can be a challenge. If the individual pieces of glass don't have identical diameters, you can add centering issues to your trouble.

[maxi0909]

Yes, regluing will solve it, but something this minor doesn't qualify as a practical problem. It may remain steady like this for years. I'd be especially careful to avoid temperature shocks, though, like leaving the camera bag in a car trunk.

This doesn't look like a balsam separation. I doubt even wide open something this minor would have an effect. I have a few Protars I have not fixed yet, and ring of crystallized brown balsam extends a couple cm into the lens. Stopped down, the lenses work fine. Compared to that, this is nothing. You'd be going to a lot of trouble to fix something that is merely cosmetic, but if that is very important to you, it can be fixed. Getting a lens like this, glued with what I assume is an older synthetic glue, can be a challenge.

Okay, that sounds good. This heavy lens should be just living in a studio, so I think there should be no problem with that, thanks :)

[Steven Tribe]

A separation, cleaning and re balsaming will work perfectly, but really this so minor that I wouldn’t bother.

Here is a similar example - found on EBay!

[Kevin Crisp]

That is not balsam separation in my opinion. The pattern plus the rainbow suggest a more modern cement.

[Nodda Duma]

It’s adhesive failure in the doublet, ie “balsam separation” although this lens is too new to have used balsam. This is what failure of modern adhesive looks like. I’d bet it wasn’t originally cured properly.