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sjalloq
1-Nov-2010, 06:27
Hey all,

first time poster here as I have a problem with a lens and thought this looked like an appropriate place to ask.

I've just picked up a Apo-Rodagon-N 80mm enlarging lens off eBay. The lens is in top condition aside from what looks like some lint on the inside of the front element. I was hoping that someone with some experience could answer a few questions:

1. These lenses aren't fully sealed so is this problem commonplace?
2. Am I going to notice the lint or am I worrying about nothing? I'm going to be using the lens for tilt photography rather than its intended use as an enlarging lens - perhaps this has an effect on your answer.
3. Would it be possible, and cost effective, to get the lens serviced and cleaned? I spent £235 buying the lens so an expensive service would probably mean I'd send it back to the seller.

Any other thoughts? Thanks.

John Koehrer
1-Nov-2010, 16:15
The lint & dust probably won't have a visible effect on the images.

BUT for that kind of money I'd either return it or ask the seller to pay for the service.
Face it, you've bought the best & should want it to be clean.

Wayne Aho
1-Nov-2010, 18:27
Lenses are not sealed, and dust can get inside over time. Most can be opened up just by unscrewing the front element (most front lenses do not need tools), then make sure that the aperature is fully open and gently blow the dust out, then screw the front element back on. I have some very old lenses that have gotten cloudy over the years, and I use a cotton swab and some denatured alchohol to clean the elements. If you do go the cleaning route, make sure that you replace any spacers that come off with the lens.

But for that kind of money, it should be in pristine shape (especially for an enlarging lens) and as John said a few bits of dust won't have any effect.

ic-racer
2-Nov-2010, 05:53
In many six-element enlarging lenses, the front 'element' is a cemented doublet. There is an air-space behind it. To get to dust in there, usually there is a circular locking ring on the front of the cell that allows it to come apart.

If the dust is between the front and rear cell, these can usually be removed by simply unscrewing them from the barrel.

If it is just a few pieces of lint, I'd just ignore it.

GPS
2-Nov-2010, 09:49
Lenses get their dust inside over time just like double windows do - if stored in dusty air the dust particles get there (not only) by the changing atmospheric pressure acting like long lasting air pump.
If "some" lint in your description means "little" it won't have any effect on your pictures. If "some" means much more than "little" it can be more irritating in some situations with some light angles, taking away a little bit of contrast.
Unless you have experience of taking apart lenses I would not try to dismantle a lens you paid for so much. You can easily make things worse even if you clean the lens...

sjalloq
3-Nov-2010, 06:13
Thanks for the advice all.

So the lint in question is about 1mm long and is curled like the letter U. I'm reluctant to send it back because the price I paid looks to be on the low end. For example, there is one on eBay US for £340 and the new price is over £600. They don't tend to come up too often on the second hand market.

I'd prefer someone experienced to take it apart for a clean but the front element is indeed held on with a small lockring. Decisions decisions..