"Does not effect image"

[Toyon]

This is easy to follow:
Its impossible to say that a lens is flawless. It is easy to say that visible defects will not have an effect on the lens performance. A bad lens with a defect will still be bad. A bad lens without a defect will still be bad. Defects, even severe ones, have little or in most cases NOTHING to do with that.

You are conflating "easy to say" with "easy to prove". You have proved brilliantly how easy it is to say something.

[Dan Fromm]

But is this a solution without a problem? How many times have you bought a used lens with a defect and been told "it has no effect on the image" and then find that it does indeed cause a problem? Has it ever happened to you?

--Darin

Darin, I've bought a couple of really crappy old lenses at camera shows with the classic "cleaned with sandpaper" look. The vendors said nothing about the scratches' effects on image quality and I made no assumptions. Two, an 80/2.8 Xenotar and a 127/4.7 Ektar, are, IMO, completely useless.

So yes, some badly abused lenses perform badly.

On the other hand, I have a 210/5.6 Boyer Zircon with ugly ugly coating damage on the front surface -- imagine a bad case of acne -- and it is actually usable.

Cheers,

Dan

[Kodachrome25]

I take the guesswork out by simply buying clean glass.

[Darin Boville]

Actually a couple of times it has. A Cintar lens I bought was strongly effected by haze, even though it was very faint and the buyer said it had effect. Why are you defending people who make statements when they are selling that they almost certainly cannot prove?

It is in the same category as "shutter speeds sound right"....of course they didn't test them, of course very few people actually test them. And, true, if off a bit it really won't make a practical difference in most people's photography just like a little blem on a lens element won't make a difference in most people's photography.

But if a seller describes an item accurately and then weighs in with his judgement that "the cleaning mark won't matter" then I bet you could easily separate out the statement of fact from the opinion, and weigh each accordingly. And if you are really unhappy just return it.

I think most people say things like "it won't effect the image" for the benefit of newcomers to the field who might be under the (very common) impression that a faint stretch on the front of the lens will result in an image of a faint scratch in their picture...people who demand perfect glass won't be buying these lenses anyways so the seller's judgement is moot...

Anyway, the question about effect on the image is unanswerable, even with your tests, since my uses might be very different from your uses and your test results might not be relevant.

Just be cool--buy with a return policy and just accept that the world is a messy place...

--Darin

[erie patsellis]

Of course, with efficient shading, most of the negative effects are easily ameliorated.

I am of the opinion that the quest for perfect glass, the perfect cameras, etc. just takes one farther and farther from making truly good images. I have some stellar lenses in regular use, yet the ones I keep going back to are the older, less than perfect ones whose "character" lends itself to image at hand. When I shot professionally, a compendium and adjustable masking frame were de rigeur, but when shooting creatively, i.e. non commercially, purely for personal enjoyment, then I tend to loosen up a bit. After all, it's just a hobby.

As the oft quoted adage goes, "it's a poor craftsman that blames his tools".

[StoneNYC]

You are conflating "easy to say" with "easy to prove". You have proved brilliantly how easy it is to say something.

HahaHahaha!!!

Burn!

:munch:

[Jim Galli]

Why are you defending people who make statements . . . . that they almost certainly cannot prove?

Welcome to the internet.

[John Kasaian]

You did not understand the post. What I stated was that a seller cannot honestly assert that a defect "has no effect" on a lens, unless it has been precisely tested in a before and after state.

"has no effect" is an opinion. That is all. It could be based on anything or it could be simply a sales spiel. Old lenses often have imperfections. They came that way. All my lenses do.
Once again "buyer beware."

[jp]

I sold a somewhat rare car some years ago after I'd had it for 5-6 years and 45,000 miles; the one and only car I'd ever bought new. The potential buyer came up from Maryland to Maine hoping for a perfect car as it had experienced minimal winter use and was in good shape. He found a minor scuff an inch long down low that could probably be easily fixed diy and declined the purchase and left on a bus. No such thing as a unrestored car in perfect condition with 45,000 miles on it. Didn't even want to bargain. It's hard to keep a "driver" car as nice as a lens. Basically, everyone has different standards of what "affect image quality" means, or like new or minty means. If you're like my potential car buyer, perhaps only buying lenses in person might be realistic. I don't sell many lenses, but I think good descriptive product photos mean more than words, and terms like image quality are not quantitative facts. Same deals with shutters... "Sounds like the speeds are good" might be accurate in the warm southwest but they might get molasses speeds when it's up here in my wintry abode.

[BrianShaw]

If I don't like the way something is described then I reserve the right to not buy. Or I ask a question and think about the answer (if one is offered). It is fruitless to attempt to change some folks sales techniques. But interesting discussion nonetheless.