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04-06-2019, 09:02 AM   #1
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Vivitar 85mm 1.8 issue

Hi everyone,
This is my first post here. I've found the forums and lens reviews a fantastic resource (thank you!) and I hope that you more experienced folks out there might be able to help with a lens issue I have.
I recently bought a Vivitar 85mm f1.8 Lens on eBay. I've heard this is a fairly rare lens, and so far has not disappointed.
Everything is in fantastic condition with it, apart from some odd marks on the glass in the front lens group. I was wondering if anyone could help identify what it might be from the photo below.
Could it be fungus? I've never seen a fungus look like that, but perhaps you have? It almost looks liquid, or like a glass defect perhaps. My best guess would be fungus that has secreted something that's eaten the lens coating, but I've never seen what that looks like, so that's a stab in the dark!
If anyone has any ideas I'd be interested to hear. I have taken out the front element to check it, but whatever it is, its on the back of the element behind which is not so easily accessible.
If it's something that can be cleaned/rectified I might look at opening it up further.

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04-06-2019, 09:47 AM   #2
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If it is on the periphery of the lens, that could be separation of black dye that is applied on the lens' side.

04-06-2019, 10:23 AM   #3
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It's the paint coming off the edge of that element. Happens to all of those.
04-06-2019, 02:12 PM   #4
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QuoteOriginally posted by vonBaloney Quote
It's the paint coming off the edge of that element. Happens to all of those.
Thanks for your input, that's handy to know! Is it easily cleaned/worth opening up to try and clean do you think?

04-06-2019, 02:39 PM   #5
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If you open it up, you'll definitely have to clean it because it will be flaking off.


So the choices are:

A) Don't do anything. Leave it as-is, and enjoy.


B) Open it up, take out the elements, blow out any internal flakes, etc, and then remove the rest of the paint that hasn't come off yet. A bit of rubbing alcohol on a cotton pad and rub the edges and it will come off pretty easily (the edges are textured). It is just going to continue to flake off otherwise, so if you open it up, there is no point in not going ahead and removing the rest of it.


subchoice B1) Now you might want to just put it together like that with no paint, and that's that. This isn't necessarily a bad choice for that lens, which is known for its soft glowy quality. I suspect the reason for that is at least in part because the paint has fallen off every copy, so maybe just go all the way in that direction and it will make it even more glowy and special in that way.

subchoice B2) Or, if you don't want that, you've got to carefully re-coat the sides with something appropriate (but thin, or it won't fit back in there), and that will maximize contrast and sharpness (hopefully).
04-06-2019, 04:07 PM   #6
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This is quite a common "feature" of some vintage glass. I have several Soviet lenses in my collection that show precisely this "affliction". I've addressed the issue on a couple of them by re-coating the edge of the affected element(s) with matt black water-based acrylic paint, but the difference in performance simply hasn't been noticeable to me, so I no longer bother with that. My advice is to leave it be and enjoy the lens
04-06-2019, 11:27 PM - 1 Like   #7
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Thanks for both of your responses there. I think I'll leave it as is in that case for now.
I've been enjoying experimenting with some of the older glass, as well as cleaning some lenses up, it's very satisfying giving them a new lease of life!

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