How should I clean a bunch of old dirty filters?

loccdor

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I've got a handful of old Series V filters with maybe 70 years of stuck dust and grime on them. Is it going to hurt anything if I give them a nice long isopropyl alcohol soak? I have zeiss wipe tissues to finish them off and handheld power turbofan to blow them dry... let me know your recommendations if you've faced similar.

Also, what's that weird cheese smell that comes from the padding of Kodak filter cases? What's that stuff made out of?
 

MattKing

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loccdor said:
lso, what's that weird cheese smell that comes from the padding of Kodak filter cases? What's that stuff made out of?
Click to expand...

For some questions, the internet doesn't really help .
 

xkaes

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BINGO!!! Most filter are tougher than you think. Try mild soap & water first.
 

RalphLambrecht

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I clean them in the sink under running water with a drop of dishwashing liquid and then dry them off with a clean towel.
 

Taylor Nankervis

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My filters are of considerably more recent vintage than a load of 70 year olds, but the cleaning regime remains the same — simple, unfussed and effective.

Let them soak in plain warm water first for a couple of hours to loosen the gunk.
Drain, refill with warm water and add dishwash.
Again, leave for an hour or so.

In the first step the soak would have loosened any gritty surface grime; in the second soak it is safe to use a soft toothbrush to work around the filter starting from the edges toward the centre.

Rinse thoroughly then dry on paper towels, turning frequently. When completely dry, finish off with a microfibre cloth.

IPA has no role to play in this cleaning; that's for in-situ use like finger smudges etc.
 

Paul Howell

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I use old bottles of Kodak lens cleaning solution. Matter of fact I just got another bottle that came with a packet of Kodak lens tissue with a Nikon N60s and set of lens I bought at an auction. Never had an issue with Kodak or other professional lens cleaning solution harming lens or filters.
 

JensH

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RalphLambrecht said:
I clean them in the sink under running water with a drop of dishwashing liquid and then dry them off with a clean towel.
Click to expand...
+1
... or take a soft tissue (paper handkerchief, Tempo).

In most cases this helps well.
If still some dirt is left, then I use window cleaner on a cotton swap.
Rarely even acetic acid.

There are filters that can't be cleaned this way, if they turned matte or have strange etched looking spots on them...

(talking about uncoated filters of the 1920s to 1950s by Zeiss, Rollei or Lifa)
 

Patrick Robert James

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A lot of old Series filters were a sandwich of a gel between two pieces of glass, so I wouldn't submerge them in any liquids or get them too wet.

Usually with really dirty filters I'll use a paper towel soaked in Windex, but not too much. That gets the grime off. Then I follow up with alcohol or lens cleaner with a Kimwipe.
 

Sirius Glass

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I would start with the simplest of solvents, water and then soap and water. Then lens cleaner from an optical company. Then maybe water and alcohol or water and ammonia. Do not rub hard and only use soft clothes.
 

F4U

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Windex and toilet paper. You don't need to drench it sopping wet to where liquid can seep past the retaining ring and osmosize into the lamination.
 

koraks

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Patrick Robert James said:
A lot of old Series filters were a sandwich of a gel between two pieces of glass, so I wouldn't submerge them in any liquids or get them too wet.
Click to expand...


F4U said:
Windex and toilet paper. You don't need to drench it sopping wet to where liquid can seep past the retaining ring and osmosize into the lamination.
Click to expand...

We'll have to disagree on the use of the term 'osmosize' here, but in general, yes, this would also be my concern. Capillary action would draw water into the filter sandwich and if these are indeed proper 'gels', this may (will) damage the filters irreversibly.
 

RalphLambrecht

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undoubtedly,but it seems that often enough, the metal ring shields the filter from that damage. Having said that, it happened ro me oonce and askoraks said, it was FUBAR.
 
OP
OP

loccdor

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Thanks everyone for the info. I knew polarizers had a sandwiched layer, didn't know that other types of filters might.

And if anyone's curious, that expired Kraft powdered cheese smell that Kodak cases have does not go away with an alcohol soak.
 
  • wiltw
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