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Topic: Lens care...

Dave Bird
Jedi Master Film Handler

Posts: 777
From: Perth, Ontario, Canada
Registered: Jun 2000

posted 02-18-2001 08:13 PM

Wondering how to clean the grunge off my lenses, what types of cloth and solution.
Also, for you outdoor operators, what do you do with your lenses in the off-season? Is freezing a concern? If you keep them in a heated building, do you want them in a dry warm room (like a furnace room) or a cooler place. Thank you.

John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 02-18-2001 08:54 PM

Here is what the Schnieder Optics website has to say about cleaning projection lenses:
http://www.schneideroptics.com/white/cleaning.htm

Edmund Industrial Optics has lens cleaning supplies:
http://www.edmundoptics.com/IOD/Browse.cfm?catid=250&FromCatID=174

KODAK Lens Cleaner and lens cleaning tissues are available at most camera stores and photography dealers.

I would recommend keeping lenses in normal comfortable room conditions (20-25 degrees Celsius, 50% relative humidity). Avoid damp or excessively warm areas.

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John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999

posted 02-18-2001 09:18 PM

We had some lenses that were stored in a basement (with high humidity.) Moisture got trapped inside, and would not come out; meaning they were always slightly foggy.

They were Benoists, which are not the best-made lenses to hit the marketplace- although I always thought the adapters they made were pretty cool (adapters to make a 52.4mm dia. lens to fit into a 62.5mm sleeve, which could then fit into a 70.6mm sleeve.)

Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 02-18-2001 09:32 PM

There are some fungi that attack the coatings especially on the french lenses
Rosco also make lens cleaning supplies
personally I think snadpaper works best

Rachel Carter
Expert Film Handler

Posts: 248
From: Gloucester, Massachusetts, USA
Registered: Dec 2000

posted 02-18-2001 11:55 PM

Personally I like the Kodak Lens Cleaner and Lens Tissue Cleaner the best, but I haven't gotten close to using all the brands out there.

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"Blood is thicker then blondes" - From the movie, Save the last Dance.

FUNNY!!!!!

Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 02-19-2001 12:42 AM

I have this pamphlet called "Care and Nurture of Coated Lenses". It looks like an old insert that Baush & Lomb used to put in their lens boxes. I suppose back in the "old days" guys used to mess up lenses by cleaning them wrong.

I have been planning to scan it and send it in. (Mainly for historical value.) I just haven't had a lot of time and I have to work out what program is best for making it into a PDF. (Any hints?)

Mark Ogden
Jedi Master Film Handler

Posts: 943
From: Little Falls, N.J.
Registered: Jun 99

posted 02-19-2001 01:25 AM

John:

That happened to me many years ago, we reopened a drive-in that had been closed a few years and found that the scope lenses were badly fogged by internal condensation.

We wound up placing them inside several kitchen sized garbage bags which we pumped full of nitrogen and then tied off as best we could. We refilled them over a few days as some of the gas would leak out, but after about 4 or 5 days the lenses were totally dry inside.

John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 02-19-2001 10:40 AM

One way to really dry something out is to seal it in a vapor-proof container (e.g., large glass jar, sealed polyethylene bag), along with a large amount of dessicant (e.g., silica gel) or Molecular Sieves. Over a period of time, almost all of the moisture will be adsorbed in this "bone dry" atmosphere. Usually has less risk than trying to dry something in an oven.

Stefan Scholz
Expert Film Handler

Posts: 223
From: Schoenberg, Germany
Registered: Sep 1999

posted 02-19-2001 01:04 PM

Not only French coatings are prone to funghi, I have also found modern hi-tech multicoating to be attacked by funghus, even in good storage condition.

John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999

posted 02-19-2001 02:37 PM

Well, the French are known for their excellent food- so maybe their lenses also taste good; at least to fungi.

Paul Mayer
Oh get out of it Melvin, before it pulls you under!

Posts: 3836
From: Albuquerque, NM
Registered: Feb 2000

posted 02-21-2001 12:19 AM

One fluid I've had real good results with is "Formula MC" (supposedly "MC" means multi-coated). It comes in a green and white plastic squeeze bottle and can be found at camera shops.

Can't resist forwarding a recommendation I got from a Panavision guy on cleaning their Primos--condensed breath! He swore by it but I haven't had the guts to try (and I admit to being easily suckered into believing things like this).

John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 02-21-2001 08:46 AM

Using condensed breath is probably less risk than trying to wipe a dry lens surface, but the condensed water vapor does not have the surfactants (cleaning agents) that the recommended lens cleaning fluids have.

System Notices
Forum Watchdog / Soup Nazi

Posts: 215

Registered: Apr 2004

posted 07-21-2010 07:44 PM

It has been 3437 days since the last post.

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Bill Slaughter
Film Handler

Posts: 3
From: Lincoln, NE USA
Registered: Apr 2010

posted 07-21-2010 07:44 PM

I know these posts are old, but we recently had a problem with moisture in a flat lens. We were advised by the head projection person in our home office to put it in the oven overnight at 150 degrees. It worked.

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