Is it possible to get a lens cleaned inside?

Quackles

Hey folks.. I have noticed some condensation inside my sigma 70-200 f2.8 ex lens.. Is it possible to get this fixed, or am I screwed? Not visible in photos yet, but I'm afraid for the future. The condensation is about half way down the barrell, I've left it in a sealed back with silica gel and it isn't working. If it's possible, where can I get it done, and have you any idea of cost?

Ta!

Borderfox

This can happen sometimes but it tends to dissolve when the temp equalises

njburke

Try putting the Lens in a warm dry place like the hot press, alternatively heat your fan oven to 45-50 degrees, place lens inside. Heat the oven from cold with the lens inside and after 30 mins or so turn oven the oven and allow the oven to cool with the lens still inside.

What you want to avoid is a sudden large change in temperature. When the lens comes up to temperature, extend and contract the lens barrell. I have done this with older all push pull zooms and some industrial lens that have been used in wet environments.

CabanSail

When you take the lens out of the oven remember to let it rest before seasoning it to taste & then serve with a light dressing of extra virgin olive oil.


Seriously, the cool oven sounds like it may work but be careful with the temperature.

Have you used the lens in a cold enviroment & then brought it inside where it's warm & humid? This can cause condensation inside gear. You can avoid this by placing gear inside a sealed plastic bag in the cold before bringing it inside & allowing the temperature to stabalise before removing it.

Sleepy

Store it in a sealed bag with a Silica Gel sachet?

Quackles

Hmm.. it hasn't been outside in ages, so I don't think that's it, and our house is roasting for the last few months because of the new baby, so I'm starting to worry that it is the beginnings of fungus instead of condensation. I might try the oven thing, although I'm petrified of it, at the end of the day, there's a lot of plastic on the lens. If it is fungus, is it a write off? It's only slight at the minute, coming in from around the edge, and it isn't affecting picture quality yet. Does anyone in Ireland clean them?

PCPhoto

Answer to your question - YES - it is possible to get a lens cleaned inside.


you can try what other boardsies have said - I like the oven idea but would be concerned about warping any part of the lens.

if you want I can have a look and if required open it up - air the internals/clean parts and close it up again.

Cheers
Paddy C

PCPhoto

any chance of pics of the condensation ?

Quackles

PCPhoto wrote: »

any chance of pics of the condensation ?

Thanks for the offer! I will try to take pics this afternoon, might be tough as it's hard to even see, you have to get the angle just right.

Quackles

These aren't the clearest.. rushed with the baby waking!

It kinda looks almost like fingerprints on the inside, you can see it to the right of the image. Sorry it isn't more clear.

njburke

On the oven thing, with the oven set low, you've got a stream of dessicated air, extending and contracting the lens will pump this air through the lens and evaporate the condensation, just use your common sense, if its too hot to keep you hand in there its too hot for the lenses.

If the lens is weather sealed, then once water gets the other side of the seal it'll remain there, putting a weather sealed lens in a bag with dessicant may not be that effective.

How old is the lens, what model is it? Some of the older optical cements use to fuse internal optical groupss together can degrade over time to become translucent. Does it look like this fogging was wiped on or like a concentric smear?

ValueInIreland

Sigma Lenses are Distributed by Hahnel in Bandon, Co. Cork. They have a good service set up, but the labour time will probably be charged at a minimum of an hour. I would try the hotpress for 24 hours and then the service route if that does not work.
Ps Don't go the oven route if you have Gas as gas gives out moisture!

zdooldreb

Sorry to jump in on your thread.
I bought a nikon 18 - 200mm at xmas and only recently noticed a mark on the lenses. I dont think its a scatch but it doesnt wipe away. I have extra careful with it and bought a cloth for cleaning.
The other day I blew on the lenses to try and get rid of some dust and, this might sound weird, a bit of saliva landed on it. I wiped it off but now I can see marks on the lense. Surely these cant be scratches?
Anything like this every happen to anyone else?

CabanSail

This is the reason you should have a UV filter on the lens.