oil on the aperture blades....

It can be bad if you have a $$$$ SLR-lens with automatic diaphragma, as the oil may influence the automatic operation and in time evaporate and leave a slight fogging on lens surfaces.

I have oily blades on my Jupiter 9 (M42) and Jupiter 3 (LTM) and really don't worry at all.

Groeten,

Vic
 
I concur with the earlier posters. It is only a problem in that it is indicative of lubricant breakdown, which implies that oil has migrated onto lens surfaces. In some cases, the oil may severely affect the sharpness and flare of the lens. In other cases, the presence of oil on the blades will have little affect onlens performance.
 
kross said:
what will happen if there's oil on the blades? will it cause fogging or affect photo quality?

It won't affect photo quality until it evaporates and deposits itself on the inner elements -- which eventually it will.

It also can cause mechanical damage to the diaphragm mechanism. Over time the oil becomes thicker and stickier, and also attracts dirt, both of which increase friction. The friction can cause the diaphragm blades' delicate brass pivot pins to shear off, ruining the diaphragm, or the blades can flex when operated, scratching the inner surface of the glass.
 
kross said:
sigh.... i got a nikkor 50mm f/2 H with lots of oil on its aperture blades....🙁

Normally the damage that happens from oily blades is a pretty slow process, so I wouldn't be too concerned that your lens has some internal oil, but you might want to get it cleaned sooner rather than later.

I have a black and nickel Sonnar made in 1932 that had oily blades and a tremndous amount of haze on the lens elements. A $45 CLA from Photography on Bald Mountain put it right, and the lens is a stellar performer. The lens was probably never cleaned between the time it was made and 2006.

I think that attracting dust and other abrasive material to the iris would be a factor with a heavily used lens though, because the constant changing of the aperture would accelerate lens wear.
 
Thanks for the info about Bald Mtn... I hadn't heard of them before. How long did the CLA take? I have a Canon 50/1.8 with oily blades & a little haze that has no effects to my pix that I can see, but I want to get sorted out.

Peter
 
physiognomy said:
Thanks for the info about Bald Mtn... I hadn't heard of them before. How long did the CLA take? I have a Canon 50/1.8 with oily blades & a little haze that has no effects to my pix that I can see, but I want to get sorted out.

Peter

phys, Photography on Bald Mountain, propietor Ken Ruth, may be reached at

http://home.pacbell.net/baldmtn. His website is baldmtn.com.

I sent Ken a Contax II and 3 lenses to overhaul. Turn-around time was about 2 months, although he said that it could vary quite a bit based on his work list. I had a good experience with the guy, although this is the only time that I have had him work on my gear.
 
Thanks Mark, I just sent an email asking whether he services ltm lenses... His site mentions that firm quotes will only be given once the item has been evaluated in person. Thanks again for the info!

Peter
 
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