Cleaning an enlarger lens

[Tom Kershaw]

My Schneider Componon-S 80mm f/4 enlarger lens has developed a haze over the last few months which I'd like to clean off, especially as I'm currently experiencing a printing issue which appears to be an optical defect. My initial thoughts are to use a microfibre cloth with a dilute solution of de-ionized water and wetting agent.

Any comments?

Tom

 

[Anscojohn]

Be gentle and sparing.

 

[Larry.Manuel]

Sounds entirely wise to me. In the old days, people cleaned huge telescope lenses with wine and a chamois. You might try the Kodak lens-cleaning tissues [I've liked them over the years, wrapped over a cotton swap for small surfaces]. Also, I do not fear using Windex[R] [glass cleaner with various useful additives]. Modern coatings are very resistant to these things. The wetting agents and streak-reducers in Windex[R] seem to work well.

I might add: laundering the microfiber cloth may be wise.

Unless the haze is severe, I wouldn't expect noticeable effects in printing. I say that because I have a mid-1930's Rolleicord with non-CLA'd, uncoated lenses, and it makes super photos. The lens is decidedly dirty, but has no fungus.

 

[ic-racer]

I agree, be gently. I have lenses that have been in my possession for 20 years and have only been cleaned a few times. The usual dust will blow off. Some haze will come off very easy. Stuff that does not come off easy is usually from fungus damage to the coating and won't ever come off. So my recommendation is always that if it does not come off easy, then stop. Otherwise you will be the one making those 'cleaning marks' that show up on used lenses

 

[Tom Kershaw]

I agree, be gently. I have lenses that have been in my possession for 20 years and have only been cleaned a few times. The usual dust will blow off. Some haze will come off very easy. Stuff that does not come off easy is usually from fungus damage to the coating and won't ever come off. So my recommendation is always that if it does not come off easy, then stop. Otherwise you will be the one making those 'cleaning marks' that show up on used lenses

Suggestions on what causes or contributes to haze formation?

Tom

 

[Bob-D659]

I had to take apart both Componon's that were shipped with my Durst D659. They developed haze on the inner surfaces including the rear of the front element. I'm guessed it was from living in a university darkroom for 40+ years. I had to use two solvents, alcohol and good old Ronsonol lighter fluid as it was not really water soluble, so I guess it might have been outgassing from lubricants in the lens? They sure are nice lenses now.

 

[Ian Grant]

Suggestions on what causes or contributes to haze formation?

Tom

Storage of enlarger lenses is an issue. I have a few Componon's and used to leave them on the enlargers, that's fine if they get constant use and it's relatively warm.

Moisture gets inside and as they warm up through use you get a thin film of condensation on the glass, over time this leaves a film on the inner element surfaces. This is probably the haze you describe. I've managed to clean my affected lenses as the elements unscrewed easily and a very careful wipe clean with glass cleaning fluid left them as new again.

Now I remove the lenses from the enlargers and store in a different dry warm room, (my darkroom is in my cellar). The problem was worst when I used a darkroom attached to the back of the house with no heating.

Ian

 

[Dave Dawson]

I use Nilglass on a lens tissue to bring lens's back sparkling.

Cheers Dave

 

[Ian Grant]

Nilglass is excellent have to agree Dave, it's the best glass cleaner available in the UK and it's what I've used for years.

Ian

 

[Martin Aislabie]

Sorry Tom, I don't want to hijack your thread.. but...

Is it a good idea to store Enlarging Lenses somewhere warm and dry (I am thinking of my airing cupboard) ?

My darkroom is a temporary affair which doubles as the Utility Room - so while dry is generally isn't that warm

Martin

 

[Tom Kershaw]

My current darkroom is suitably temperature controlled, however my previous shed based darkroom was not so.

Tom

 

[Philippe-Georges]

A former technician from the 'Oude Delft' told me that the best 'liquid' to clean lens-surfaces was spit (yes the mouth-water). Spit has enzymes in it that solutes dirt and micro organisms. Just keep the lens-part (the glass) in your mouth (cheek) for about 10 min. Then you can clean the lens with any 'chemical' you find suitable.
If you, by accident, happens to swallow the lens-part, it will come out the other end a few days later and the dirt and nicro organisms will be gone too...

Be careful when reassembling and aligning the optical elements.

Philippe

 

[steven_e007]

I clean optics a lot in my day job. Any optical surface will get a grubby coating with time, almost anywhere it is used or stored. Some places are obviously much better than others, but the air is never completely clean - none of us print in a clean room. Many camera lenses have an age film on them, the owners just haven't noticed! It is much more noticeable on optics where you shine light through the lens - such as enlargers and projectors. The best way to show up grime is with one of those LED torches, a single blue LED seems to be the best. Shine one of these through a lens in a dark room and look through from the other side. It shows up the dirt extrememly well and it is often possible to work out which surfaces it is on, too.

As for storage, I think the biggest problem with fungus is humidity. Not sure of all the ins and outs (not being a mycologist!) I just know that equipment sold to India seemed to have a lot of trouble with fungus (hot and humid)... Maybe an airing cuphoard might be a bad idea.

The biggest problem with cleaning optics is scratching the lens. For this reason I don't like rubbing with a dry cloth or tissue. A lens should be cleaned wet - wash rather than scrub - and make sure you blow any loose matter off with a brush, first. I prefer to use hand wound cotton wool buds (on a wodden shaft) and a solvent. It is difficult to get decent solvents, these days, due to health and safety and anti-terrorist legislation. Pure ethanol might be the best you can do, although it isn't really volatile enough. Petroleum Benzine (also called Petroleum Naptha) is good, but it really needs to be pure reagent grade. It is basically lighter fluid - but the stuff in the tin can sometimes be a bit oily, which isn't helpful... Most lens cleaning fluids are demineralized water with a dab of detergent and a few percent of ethanol. They don't do any harm, but they aren't much good at cleaning, either...
Acetone is a good lens cleaner - but it is even better at seperating balsam (real or synthetic), dissolving paint and damaging lens mounts. Don't even think about it!
Just my humble thoughts...

 

[Martin Aislabie]

Hmm...

Steve, very interesting

Martin