Fungus in my old Schneider Companon f5.6 80mm lens

[Joyful]

When I got my old Opemus enlarger back, I saw that the lens was cloudy. In the olden days I made 20 x 24 inch pin sharp B&W prints using it - hard to say goodbye to an old friend !

Is it worth while trying to get this lens fixed - there appears to be a silvery something over the majority of the inside of the inner assembly (the bit normally between the negative and shutter) ?

How difficult will it be for me to try and clean the glass elements myself, and what would I need to use to remove it if it is a fungus ? I live a few hundred yards from the sea, and the lens has been in my cupboard since about 1985.

I plan on visiting a marble and granite showroom tomorrow morning to discuss getting offcuts and help making camera and subject plinths in granite, and then going to a Camera repair shop for their opinion, or at least their help in opening the lens.

What is the forum's opinion of this lens when it is in mint condition - is it worth spending money on it ?

Joyful

[Pau]

Schneider Companon

Componon or Comparon? Componon are of higher end series and very likely better.

If the lens is heavily fungus infested just trow it, even more if the fungus are in internal elements whose coatings are usualy softer than the external elements ones.

[Joyful]

Hi Pau -

Definately Componon. Way back in 1972 when I bought it new, it cost me R75.00. The year before I had bought a new Hasselblad 500C/M for R750.00, so it was a good lens - very good actually.

Joy

[jjphoto]

Enlarging lenses are generally very easy to dismantle to clean depending on the lens and extent of the fungus. You are much better off having a go at cleaning it yourself as you really have nothing to loose. If you pay someone you might pay more than it would cost to replace the lens!

I don't have a componon 5.6/80 (I have many of the same design) but I suspect it is in three main sections where the front and rear lens groups just screw into the central main section (housing the aperture). Unscrewing the front and rear groups exposes the glass surfaces exposed to the aperture blades inside the lens however it doesn't expose the glass inside the front and rear groups themselves. To do this usually requires special (albeit inexpensive) tools.

Cleaning the fungus out is not hard, isopropyl alcohol is normally used. As already mentioned if the fungus has been there a while it will have etched itself into the glass so no amount of cleaning will fix that.

[Carmen]

jjphoto:

Given that the fungus has etched the surface of the glass, is it posible to polish enough to remove damage? at least in principle? perhaps at a optics shop, or maybe at profesional telescope mirror grinder shop?

[Joyful]

Hi Carmen -

Yes it is possible in principle, but not recommended for two reasons - first is that the polishing will probably change the optical properties of the lens, and second - a proper polish without changing the optical properties is likely to be very, very expensive.

I was quoted from R400 to R800 just to open up the lens and have a look, and was told if the fungus had eaten into the lens then there was nothing that they could do.

To put R800 into context - it is a little more than the cost of a brand new Nikon 10x achromatic lens.

Joyful
PS - My Conical adapters have been despatched !

[Carmen]

thank you joyful! that makes sense!
p.s. I received new kit!

[Photo-DIY]

...
Yes it is possible in principle, but not recommended for two reasons - first is that the polishing will probably change the optical properties of the lens, and second - a proper polish without changing the optical properties is likely to be very, very expensive...

As an optical engineer I thought this would be a big problem.
But to my astonishment my experiments show no striking quality problem after DIY lens polishing.
For sure exact measurments will likely show a lower quality after polishing a lens with this simple method.
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[Joyful]

Hi Markus - Many thanks for that !

Perhaps you can recommend some polishes that I can use on my reading glasses that live around my neck - they are getting badly scratched to the point where I try to clean them constantly - no luck.

I do not have an electric drill - so I would need to polish by hand. I tried Brasso polish (I remove scratches from CDs and DVDs using it), but the glass is a lot harder.

What else can you recommend ?

Joyful

[g4lab]

You could try Cerium Oxide metal polish which is sold in a tube in an ammoniaical carrier. It is sold under the names Wenol Pol Flitz and Happich Simichrome. You can usually find it at bicycle and motorcycle shops.

It works great on metal but should also work well on glass too. Cerium oxide is regularly used as a gemstone polishing agent on materials much harder than glass. Actually so is tin oxide which iirc is the polishing agent in Brasso.
I have polished lots of non metallic things with CeO polishes.

[Photo-DIY]

...
Perhaps you can recommend some polishes that I can use on my reading glasses that live around my neck - they are getting badly scratched to the point where I try to clean them constantly - no luck.
...

I got my Nirgin car glas polishing agent from a car repair shop. That is intended for glass and works well. But depending on glass / coating hardness it takes even with the drill soem time.
Old Helios 44 coating goes fast away, but newer ~1990..2000 Sigma coating needs much longer, probably 4 times as long.

[parcival]

As an optical engineer I thought this would be a big problem.
But to my astonishment my experiments show no striking quality problem after DIY lens polishing.
For sure exact measurments will likely show a lower quality after polishing a lens with this simple method.

Thanks for posting that link, i've got a few oculars that got badly scratched through improper cleaning by the previous owners and this looks like a way to make them useful again.