A "good copy" of a lens

I am getting a Canon 24-105mm f4 L. When searching the web I found all sorts of stories from people getrting dud 'L' series lenses (though mostly Canon 24-70mm L) so it seems a possibilty that I would like to be ready for.

So what do I do if I get a bad "copy" of the lens?

And, actually, how do you tell anyway if the "bad copy" lens is only a little bit bad copy and still better than the lenses you had before (which you sold anyway to get the new one)?

P.

Peter

I'm sure others will wish to come in and comment on this one. You will also find reams written on the subject in various fora all over the internet (as you have suggested).

However, one sage piece of advice and comment that is on a post somewhere on this site is along the lines of the number of people who claim to have a 'poor' lens when what is deficient is their knowledge and skill at using it properly.

Get the lens. Put it through its paces. Get to know its every nuance and every capability. Don't ask it to do things it wasn't meant to do. And, then, if you think the results aren't matching up to the amount of money you spent, do something about it.

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how do you tell anyway if the "bad copy" lens is only a little bit bad copy and still better than the lenses you had before

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If you are happy, then it's a good lens.

Hi, Peter;

I had exactly your experience, not with an L-series, but with a top of the line EF-S (17-55 IS USM). I expected it to be much better than the kit 18-55 IS, and in some side by side testing, it was definitely better. I probably should have realized that it was only a little bit better, and should have been a lot better. But over the course of 3-4 months, I just felt that it wasn't what I had expected. Based on reading a lot of the same things you've probably read, I invested in Imatest, and the results didn't seem what I expected, so I sent it in to Canon.

The (fairly) happy ending is that Canon got it back to me in less than a week, fixed for free. The reason I say "fairly" happy is that I shouldn't have had to pay for shipping to get a brand new lens fixed, but I had no way to prove it was broken when I got it. The paperwork that came back said: "Your product has been examined and it was found that the adjustment of the part was incorrect causing the auto focus to operate improperly," so there really was a problem.

One reason I didn't catch on right away was that, similar to Donald's point, I was just getting up to speed with a new camera body at that time (500D). My wife has just recently gotten me a 100mm L-series macro lens, and by the end of the second day, I was certain there was no problem with it. I haven't even bothered with the Imatest stuff. I probably should, just to have a baseline in case I drop it, but I have no doubts about the quality of the new lens.

So I agree with Donald: get the lens, learn it, and use it. If you think it isn't performing, send it to Canon: all it will cost is the shipping, and they'll at least clean it and calibrate it. You can also take it to a camera shop or something, but I think they charge you more than shipping costs.

Cheers,
Rick

Hi Peter,

Personally I'm not a big believer in the "bad copy" mantra - most of the time and "softness" seems to be due to a complete absence of capture sharpening. I'm the fussiest person I know - I've had "quite a few" Canon lenses - and never had anything less than 100% satisfactory.

If you want to test a lens though, simply photography something with fine detail (RAW) - apply capture sharpening - and examine in Photoshop at 100% magnification. If the results aren't satisfactory then send it to Canon to be recalibrated.

Not familiar with good or bad copies of lens, could it just be a poorly manufactured series?

There is a good story at http://lubowphotography.com/tamron-canon-test.htm.

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Originally Posted by peter2108

There is a good story at http://lubowphotography.com/tamron-canon-test.htm.

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All I can say is that that chap seems to have a lot of bad luck with Canon lenses. My 24-70 has been just fine, and I haven't needed to use the new microadjustment feature of the 1Ds3 either.