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07-14-2014, 02:11 PM   #1
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Cleaning an old Push-pull lens?

I recently found a cheap Tokina Szx 80-200 for sale on Ebay, the listing claimed the lens was "like new" and "clear", when it arrived it had odd stains on one of the interior elements. They look like dried fluids, perhaps someones took a crack at cleaning the elements, and didn't let things dry? The seller was nice enough to offer a full refund, without requiring me to ship it back to him; so now I'm stuck with a dirty, but free, lens.

Being that the stains are so large (perhaps covering 10% of the element, the lens is worthless, so there is no real loss if I try to fix it and fail.

Anyone have any experience at cleaning these? The strains appear to be in the second element, the one right behind the front piece of glass. The other elements appear to be in mostly good condition.

07-14-2014, 02:42 PM   #2
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point 1: might look bad but does it affect the pics? actually takes a lot to do so as this post illustrates:
LensRentals.com - Front Element Scratches
point 2: lens dissassembly is easy to get wrong and/or damage st. ut if you're keen then start googling, there's plenty of others who have got stuck in and who have posted about it. here's a starter:
Basic techniques to repair lenses (and cameras)
07-14-2014, 03:58 PM   #3
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I haven't given it a full test yet, since it needs some heavy cleaning on both the front and back elements, but looking at it; I'd say it would. The first internal element has what looks like thick dried drops all over, which are transparent but still obvious (these cover over 50% of the element), at the bottom of each of these is a large drip of what appears to be dried foam, these are completely opaque, and cover around 10%, in the very center of the element. Between them, I'd say that most of the internal element is affected, not just a couple spots.

As I said, though, I haven't had a chance to test it. I just got back from vacation, and am about to go on another trip in a day, so... No time for much. With the full refund, though, I figure the worst case scenario is about as bad as now. If I kill it, I'm in pretty much the same situation as I am now... With all my money, and lacking a usable lens.
07-14-2014, 04:03 PM   #4
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sounds like fungus
The Flashlight Test

07-14-2014, 05:53 PM   #5
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QuoteOriginally posted by marcusBMG Quote
sounds like fungus
People who capitalize "Leica" belong in the same circle of hell as people who capitalize "Mac" (as in Apple MacIntosh).

That said, useful article... I thought it was fungus as first, until I noticed the all the white spots look kind of like a "C", with a thick spot at the center, and on closer examination, they seem to be little circles, with one edge thick and opaque. Each opaque edge faces in the exact same direction, almost like a drip.
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07-14-2014, 07:59 PM   #6
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It looks to me as if the lens were completely submerged in something (salt water?) and left to dry on its own.
07-15-2014, 09:19 AM   #7
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Yeah, its pretty horrible. I'm not sure if it is really fixable. I did some cursory cleaning, and it looks like even the inside of the front element is dirty.

Very odd that anyone would list it as like new or clean. I don't suspect dishonesty, since the seller offered a full refund without the expectation of return.

07-15-2014, 10:32 AM   #8
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Not an easy task. The best advice I can give you is to document every step of the disassembly thoroughly. For instance, use a large (large) piece of white paper or cardboard. Tape and label every item you remove, numbering the steps. Take pictures at each step. Don't loose anything. Take your time. If you see anything that looks like a spring, take things very slowly and be extra careful. And cross your fingers.
07-15-2014, 10:37 AM   #9
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You made it sound like I'm defusing a bomb.

Cut the red wire, or blue?
07-15-2014, 11:44 AM   #10
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He's right though. Remember that you'll want to put it all back together again.

If you are lucky then all that crap will be on the outer surface of the front or rear group and you won't have to go in too far. With the push-pull your fun bit will be screwing the big helicoid back, it will usually go in in several orientations, only one of which is correct. Mark everything before you unscrew it
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