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02-01-2011, 08:23 PM   #1
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Okay, I know my Super-Tak is yellowed, but...

This is mildly ridiculous (that and I'm 87% sure this isn't cause of the yellowing.

So I was just trying out my Super-Tak 50/1.4 in the sun (cause we just got sun for the first time in forever) to see how its (earlier/inferior) coatings hold up against the sun. I wasn't too dismayed by the flare - it could be put to good use with some creativity, but I WAS surprised to see a whole bunch of orange...not sure what. Any ideas as to what it is?

They were shot through my window's mesh, so maybe some diffraction from the wires or something? I shot it again by going outside, so no mesh, but then the sun was behind some clouds and I'm not sure if that's responsible for the lack of orange whatever-the-hell, or the lack of mesh, or something else. Any thoughts? Pictures below:







02-01-2011, 09:35 PM   #2
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I wouldn't rule out diffraction, but it seems a little hard to believe, given how irregular the patterns are in the orange stuff. One would think something more orderly would pop out of the grid of a screen, hm. I suppose that wasn't helpful at all, sorry!
02-01-2011, 09:41 PM   #3
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Hey, so I screwed around heavily with curves and whatnot on your outdoor image because the photo you posted looked like it still had subtle signs of the orange stuff. You can see it more clearly in the heinous editing I did, which makes me wonder -- how clean do the optical surfaces look on your lens?
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02-01-2011, 09:54 PM   #4
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Looking at my lens through a pretty bright (almost painful to look into) white reading lamp reveals that it's just as clean as my other lenses - a bit of dust on the front element, maybe a speck or two in the internal ones, and more on the rear, but nothing out of the ordinary. My kit lens, which I abuse, probably has more. The mystery continues...

02-01-2011, 10:01 PM   #5
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I just took a shot of some white paper under the aforementioned white reading lamp, then put those shots in LR, cranked up contrast, clarity, and saturation all to the max. Here're the results at wide open and F4, respectively:





I guess the oranging was always there, but the unprocessed image looks totally neutral.

Could it actually be the lens's yellowing? Never heard of it being uneven across the lens (and looking through it seems like it's pretty centered); also in the cloud shot after you processed it, there seem to be flecks of orange, as opposed to an even colouring....Hmm.
02-01-2011, 11:47 PM   #6
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I'm thinking someone tried to clean this lens with something and it messed with the coating. I have a yellowing 50. It's actually more of a golden tint, but it's the whole lens. That looks like something acidic was used to clean it, something not made for photographic lenses maybe. It almost reminds me of the mineral buildup you see on some windows over time.
02-02-2011, 12:06 AM   #7
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QuoteOriginally posted by magkelly Quote
I'm thinking someone tried to clean this lens with something and it messed with the coating. I have a yellowing 50. It's actually more of a golden tint, but it's the whole lens. That looks like something acidic was used to clean it, something not made for photographic lenses maybe. It almost reminds me of the mineral buildup you see on some windows over time.
Well that's a bit disappointing to hear. How certain are you of this?
02-02-2011, 07:33 AM   #8
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Ckeck out threads about "Takumar 50mm f1.4 Radioactive?" May answer your question.

02-02-2011, 08:43 AM   #9
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QuoteOriginally posted by Jimmy637 Quote
Ckeck out threads about "Takumar 50mm f1.4 Radioactive?" May answer your question.
Not my question
02-02-2011, 11:28 AM   #10
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I wouldn't be concerned until you get outside and really shoot with it.

As an owner of the same lens, I can tell you that I see zero evidence of flare or wash out because of it's "inferior" coating compared to the s-m-c.

Mind you, I have no yellowing, so maybe my original coating is better intact.
02-02-2011, 12:28 PM   #11
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QuoteOriginally posted by jaieger Quote
Could it actually be the lens's yellowing? Never heard of it being uneven across the lens (and looking through it seems like it's pretty centered); also in the cloud shot after you processed it, there seem to be flecks of orange, as opposed to an even colouring....Hmm.
I don't think it's the yellowing. My 50/1.4 has some yellowing as well, and it's very even. It just make the whole image warm, which can usually be fixed by playing with the white balance a bit in PP.

In your first shots of the flare through the screened window, the orange patterns had areas where the discoloration was much more concentrated, so I don't think the outdoor image is simply showing 'flecks' -- I think the hazier orange tendrils are simply too faint to show up. I'm going to agree that this is probably uneven damage to the coatings caused by bad cleaning technique/chemicals.

However, I really have to strain myself to notice any problems in the shots of the white paper, which makes me think this won't really detract from your images unless you're shooting towards a bright light source where flare is possible. I recommend going out and playing with it to find out
02-02-2011, 07:33 PM   #12
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Thanks for the replies, all. As it turns out, the local camera shop I bought this from still has this on warranty (two days away from it expiring though), so they'll send it to their repair center and see what they can do. Hope they don't make things worse...God I hate the phrase "reserve the right to___", if they'd just refund it I could find a better condition one and life would be simpler
02-02-2011, 11:17 PM   #13
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I can't speak for camera lenses but I have seen something similar to this on eye glasses, on window glass and in particular on good crystal bowls that have been used from time to time as vases. The bowls in particular remind me of this. They had an transparent AB coating (rainbow) and the more we tried to clean them with the standard chemicals that were bought to do that the more they got like this. It was the chemicals. It turned out they were anything but safe and the coating went a yellow orange and eventually stripped off completely.
02-02-2011, 11:51 PM   #14
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Well that's a damn depressing account as far as my lens goes, but good to know at least. Makes me doubt if the repair center will be able to do anything at all if it's coating-related, but here's to hoping...Shame too, the lens is in otherwise pristine condition.
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