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03-06-2014, 09:52 PM   #1
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Is element separation a common problem for FA/F 135/2.8?

DA 50-135 is a great lens but is just too heavy to carry around. So I want to buy an FA/F 135mm 2.8 lens to replace the bulky 50-135, since I have nice primes 55/1.4, 77, sigma 105 macro already.
I managed to purchase two copies. One FA and one F version. One from the market place here and one from ebay.
Unfortunately, and surprisingly, both copies I bought had a similar problem: an internal element exhibits bad foggy rings. One copy was worse, only 1/2-2/3 of the center is still clear. At first I thought it was dust and unprofessional cleaning. But the 2nd copy came in today and I saw three rings affecting ~1/5 area. See photos. When I saw the second copy, I realized both lenses might have element separation.
both sellers are nice and responsible. I am not complaining here.
But I am really surprised both copies I got had this problem. Is it a common issue for this lens? I did a search online and found nothing.
Any inputs here? AM I wrong that these are not separation but dust?

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03-07-2014, 02:08 PM   #2
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Any examples of photos taken with these lenses?
03-07-2014, 03:29 PM   #3
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Images taken from them are still very good, wonderful shall I say. A little CA at 2.8, but resolution is very good already. My 50-135, which is very strong at 135 end, produced comparable resolution in the center @ 2.8, but the edges are much better for prime. Stop down to 4, the prime is much sharper than DA* ZOOM, from edge to edge. I just got the lens, and don;t have any photo that can share, expect some boring testing shoots.

I was expecting some sort of "soft-focus" effect from the haze, but was surprised not seeing that. Of course I don;t have a good copy to compare. maybe a clean copy can produce even better.

If I can confirm that the haze at the edge is from dust, I will keep the lens. They really doesn't affect IQ too much, if any. But I am afraid the separation, if it is, would get worse and worse, the 2nd copy will become 1st copy and eventually covered by haze in the entire glass.

Any thoughts?
03-08-2014, 09:14 AM   #4
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My copy does not show any separation of the elements or dust, and is very sharp with nice bokeh, but can exhibit a fair amount of PF wide open.

03-09-2014, 07:17 AM   #5
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Can't comment on the F 135 2.8 , but I've owned two copies of the F 100 2.8 macro and they both had the foggy rings on an internal element.Could they possibly share the same
internal components?They were both plenty sharp,despite the haze.Just my two cents.
03-09-2014, 08:34 AM   #6
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Also both of your copies? That is sad.
Are the foggy rings stay like the first day you saw them? Or they are slowly progressing?
i am still debating whether or not to return the lens. It is still very sharp lens, and I really like the compact size and fast AF. I planned to replace my 50-135 with this. If the rings, once they show up, will stay stable for very long time (many years), I will probably keep it. The rings do not affect IQ, at least on APC cameras.
03-09-2014, 08:57 AM   #7
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QuoteOriginally posted by grahame Quote
Also both of your copies? That is sad.
Are the foggy rings stay like the first day you saw them? Or they are slowly progressing?
i am still debating whether or not to return the lens. It is still very sharp lens, and I really like the compact size and fast AF. I planned to replace my 50-135 with this. If the rings, once they show up, will stay stable for very long time (many years), I will probably keep it. The rings do not affect IQ, at least on APC cameras.
Yes,both copies.I had them a couple of years and they never seemed to progress any further.I think it would be a slow process to degrade to the point
of non-useability IMO.
03-09-2014, 09:37 AM   #8
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QuoteOriginally posted by 17dew Quote
think it would be a slow process to degrade to the point of non-useability IMO.
Thanks. That is what I want to know. If the lens will have 5-10 years of life left, I will probably keep it. It is a quite rare lens and performance very well.

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