Dust inside a lens...

[Ara Ghajanian]

Okay. So I bought a Nikkor 55mm Micro on eBay and the seller said the lens was clean, free of fungus, no oil on blades, etc. I got the lens and I checked it out. It's got a pretty good amount of dust inside the lens on the various elements. There doesn't appear to be any on the rear element, but there's some on the inside of the front element and definitely a lot on the inner elements. I've never had such severe dust on a used lens. Does this really affect lens clarity, etc? Can anyone give me some advice on this? Can I get it cleaned and does it cost a lot?
Ara

 

[Lee Shively]

It probably won't affect the photo quality but you should test it.

That's a super sharp lens, by the way.

 

[Mongo]

You can get it cleaned if you want to...but you'll probably have to pay something in the range of US$100-150. Basically a full CLA on the lens. (The lens will have to be disassembled completely, so there's no reason not to do the full CLA as the real work is in taking the lens apart and putting it back together...the actual cleaning and adjusting is pretty minor stuff if the lens is working correctly.)

But in reality, you probably won't see the difference in the quality of the images. You can shoot a test roll to see if the images look good to you; if they do, then don't bother having it cleaned. If you get the CLA, you'll find new dust in the lens in another few months anyhow. Because of the way 35mm lenses work, dust is basically sucked into the lens during focusing. Unless a lens is completely sealed (a rare thing indeed as it's hard to make a lens work well if it's sealed), you will get dust inside. But it takes a lot of dust inside of a lens before you can detect the effect even with instruments; with the naked eye it takes even more.

I'd just use the lens. I'm betting that you won't find any visual degradation due to the dust.

 

[Ara Ghajanian]

Lee and Mongo,
Thanks for the reassurance. I can breathe easy now. I had a feeling it wouldn't affect a thing, but I had never had that much dust in the lens. I am going to write an email to the seller to let him know that he shouldn't be calling a lens 'clean' if it really isn't.
Thanks,
Ara

 

[Mongo]

Ara-

I should have mentioned: My dustiest lens is a Nikkor 105mm f/4 macro. If you looked into this lens you'd wonder how it ever took a good picture...but it's by far the sharpest, most contrasty lens I own for my Nikon. A macro lens used in macro mode would be the first place I'd expect to see the effects of dust...and I see absolutely nothing with this lens. I'll bet your 55mm is just as good.

Be well.
Dave

 

[Russ - SVP]

Ara

It'll have no affect on the image quality. Use, and enjoy it.

Kiron Kid

 

[Ara Ghajanian]

Thanks for your blessings.
Ara