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05-02-2012, 04:56 PM   #1
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Lens issue

I picked up a Viv 75-205 f3.8 k-mount, but it seems to have a problem (luckily the seller refunded my money without a problem).

It seems that the lever that controls the aperture is extremely sticky. The aperture is stuck wide open, unless I push the lever at which point it closes down. From there, it does not open up on its own again and nor does the lever move back on its own. When I push the lever back and hold it, the aperture very, very slowly opens again.

I made a video of how the lever gets stuck:

Has anyone experienced this and know if it can be fixed?

Thanks.

Steve

05-02-2012, 05:08 PM   #2
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Could be oil on the aperture blades. Usually you can see that if you look, maybe using a flashlight. If you watch ebay listings you will often see a lens listed as "fungus and oil free". What happens is that some of the grease from the helicoid gets onto the aperture blades. They need to be clean and dry to work properly, just the slight reistance (stickiness) of a little oil is enough to mess them up.

It could also be a bent aperture lever that is rubbing on something, but most likely oil on the blades.

When shopping for used lenses always take a flashlight and check carefully for fungus and oil on the blades.
05-02-2012, 05:59 PM   #3
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I looked and it appears that there is some oil on the blades. I guess there is nothing that can be done, right?

Thanks
05-02-2012, 06:30 PM   #4
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The lens can be cleaned. Whether it is worth the cost is another issue. If you have the tools and skills you can take it apart and clean it yourself or get a price from any camera repair shop. That is a nice lens but is usually not very expensive at auction. If it was me and the seller was willing to refund I would do that in a minute. Don't know what you paid but I would guess the cleaning would be more than that.

05-03-2012, 04:33 AM   #5
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Thanks jatrax....luckily the seller was very accommodating and refunded the cost of the lens excluding the cost of shipping which I thought was fair given that I got a Hoya HMC UV filter, lens caps and a nice case with it. I really wonder how much it would cost to clean it, although I can imagine it would probably be too much.

Anyway, maybe I will try to take it apart, but I am not sure what has to be done to clean it. I guess I will look around for videos and Web sites that explain it, although I am not confident that what I will do to it won't make it completely unusable.
05-03-2012, 07:40 AM   #6
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Not sure if this lens is made by Kiron, but Kiron lenses from the early 1980's seem to really suffer from oily blades. I have 2 wide angle kirons, a 24/2 and a 28/2 and both had to be cleaned. I am not alone with early kirons and this issue, as other members have also posted these problems seemingly more often than other lens makers
05-03-2012, 08:48 AM   #7
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QuoteOriginally posted by Spodeworld Quote
Anyway, maybe I will try to take it apart, but I am not sure what has to be done to clean i
I would stop in a local camera store if you still have one and ask for a quote on getting it cleaned. No cost to you and maybe they will answer some questions. But if you have not done lens repair before, and have the proper tools, you will likely not have a good experience. I have taken a number of Takumars apart and successfully repaired and rebuilt them but they are very simple lenses compared to others.

I understand that cleaning the blades involves opening the lens to the point you can get access to the blades and then removing the oil with a solvent, acetone is sometimes mentioned but not sure if that is best. The problem I see is getting the residue out of the lens without just spreading it around.

Good Luck!
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