How many times did you return (L) lenses to get a good copy?

[Marsu42]

I just bought a new 17-40L, and I'm happy that I didn't get it from ebay (the offers weren't good enough vs the current Canon rebate program) because the lens shows visible decentering - see attached 100% crops of bottom vs. top, my first thought was that the chart was tilted... but it wasn't me or the camera and now I'm going to get a replacement from Amazon.

I wonder how many times your lenses were exchanged (or how many copies you tested side by side) until you received a lens that was a good copy?

Looking at the crops, would you also have returned the lens, or is something like this to be expected and I'm spoiled by better lenses?

Btw, if anyone wonders: As far as I tested it the 17-40L is a good (landscape) zoom lens for the money even on crop, it's just the corners and that it doesn't reach max. sharpness wide open but needs to be stopped down a little to f5.6+

Edit: afma should be no issue @f4+ and my 60d doesn't have it anyway ... with this 17-40L copy I couldn't tell lv from phase af. The crops are of course focused with contrast af and shot on tripod with mirror lockup.

 

[rs]

Re: How many times did you return lenses to get a good copy?

Sigma 50/1.4, once. The first copy front focused so much that even thumbnails of the images appeared badly OOF. My second copy nails the focus.

 

[neuroanatomist]

10 L-series lenses bought new (and thus, able to be exchanged), all of them good copies (at least, based on resolution testing with an ISO 12233-type chart, etc.). Next lens will likely be the 24-70/2.8 II, hope my streak holds...

 

[Dark Reality]

I've never returned any of my lenses for a new copy. I rarely even test them to the degree that many seem to. I take a bunch of test shots before buying, but that's pretty much it. I have the first versions of the 24-70 2.8, 70-200 2.8, and have owned at one point several other L lenses, and honestly, I know I didn't have a "bad" copy, but I couldn't tell you if it was good, or just average or whatever. I've never noticed a problem and either has anyone else. Maybe I'm lucky, idk.

 

[Meh]

10 L-series lenses, all of them good copies (at least, based on resolution testing with an ISO 12233-type chart, etc.). Next lens will likely be the 24-70/2.8 II, hope my streak holds...

I'd suggest a trip to the casin0 but I suspect the odds of getting 10 good L lenses are more favorable than most card games.

I have 4 L lenses and as I can tell they are all good. Never shot a test chart though... perhaps I should.

 

[Meh]

FYI... c a s i n o appears to be a blocked word in comments... Security Alert!!!

 

[CharlieB]

I own eleven Canon lenses at the present. I've owned sixteen in total - some having gone to friends.

Gotta say, I've never had a bad one. I have had ONE lens - a 50/1.4 that had some issues which Canon cheerfully took care of in their usual expedient manner (about two weeks as I recall).

I have a 7D that was a real hoot for focus... it simply would not focus... but Canon also fixed it up, and while some lenses still need AFMA on that body, as they do on other bodies for absolute best performance, it has become my focusing favorite now that Canon has massaged it a bit.

 

[jeffabbyben]

I had to return a 16-35 that was absolutely unacceptable in the left and right lateral 1/4-1/5 field of view at f8 and beyond. Second copy was much much better. Didn't even need a test chart for that one ;D I have owned/own 5 different L lenses so I feel I have had a very good experience.

 

[mrmarks]

I have 5 L lenses and never had any "real" issues with them to justify a return, even after thousands of shots. I did AFMA tests on all of them and none really had any need for any adjustment with my 5D2 and 5D3 bodies.

 

[East Wind Photography]

Tried 3 copies of the 100-400L and ended up returning the last one in favor of the 70-200 2.8l is II and 2xiii extender. At 400mm the 100-400 was soft enough wide open that it interfered with AF lock. It also focused slower than the latter with the extender.

I didn't see the point of suffering. I don't believe they were all bad copies but rather a design "flaw"

 

[birtembuk]

Got 4 so far, and all are just fine. I don't order but buy from what I would call a pro shop. The guys there let me try and test with 100% view on comp. I prefer to pay some premium for those premium lenses rather than to take the risk to have a copy that doesn't satisfy me. My next is 16-35 and then 24-70/II and I will sure take the time to check those babies fine. Heck, when we get our plastic to overheat so much, we want to ensure the best, don't we?

 

[neuroanatomist]

Tried 3 copies of the 100-400L and ended up returning the last one in favor of the 70-200 2.8l is II and 2xiii extender. At 400mm the 100-400 was soft enough wide open that it interfered with AF lock. It also focused slower than the latter with the extender.

I didn't see the point of suffering. I don't believe they were all bad copies but rather a design "flaw"

Interesting. My 100-400 at 400mm is slightly sharper than my 70-200 II + 2xII or 2xIII, which is consistent with the TDP data (ISO 12233 crops). I find focus speed in simple situations (bird on an isolated branch or flying with open sky behind) to be faster with the 100-400 at 400mm, but in complex situations (small bird in a thicket, for example) the 100-400 has trouble locking whereas the 70-200 II + 2x does not.

 

[RC]

First copy of my 24-105 had an air bubble in the outer element. Replacement copy was just fine.

 

[distant.star]

.
All my lenses are the real things. I'm not putting out that kind of money for copies!

 

[RC]

.
All my lenses are the real things. I'm not putting out that kind of money for copies!

 

[East Wind Photography]

Might also have to do with the body it's used with. The AF issue is related to diffraction when the lens is wide open. Images taken wide open show halos on highlights softening the edges. The AF system has trouble getting a good lock due to unsharp edges. It's a good test up front when a lens produces soft edges wide open it will often have difficulty locking on images that have noisy backgrounds or low contrast. The 70-200 was sharp wide open so the AF system works more efficiently.

Tried 3 copies of the 100-400L and ended up returning the last one in favor of the 70-200 2.8l is II and 2xiii extender. At 400mm the 100-400 was soft enough wide open that it interfered with AF lock. It also focused slower than the latter with the extender.

I didn't see the point of suffering. I don't believe they were all bad copies but rather a design "flaw"

Interesting. My 100-400 at 400mm is slightly sharper than my 70-200 II + 2xII or 2xIII, which is consistent with the TDP data (ISO 12233 crops). I find focus speed in simple situations (bird on an isolated branch or flying with open sky behind) to be faster with the 100-400 at 400mm, but in complex situations (small bird in a thicket, for example) the 100-400 has trouble locking whereas the 70-200 II + 2x does not.

 

[Badger]

I'm a bit embarrassed to admit this, but I'm not even sure what to do to test a lens. I have had lenses I was frustrated with, but always assumed it was me. Can you all give me some guidance on how to test lenses? I do have two L lenses including a new 25-105 IS that I got with my 6D. I am honestly not too excited about it when it comes to sharpness.

 

[East Wind Photography]

Look up Reikan FoCal Pro. See if your camera is supported. You can run focus tests and recalibrate yourself. It also can run through all F stop settings to determine which stop provides the sharpest image. It's not 100% but its nice to know where your lens sweet spot is.

I'm a bit embarrassed to admit this, but I'm not even sure what to do to test a lens. I have had lenses I was frustrated with, but always assumed it was me. Can you all give me some guidance on how to test lenses? I do have two L lenses including a new 25-105 IS that I got with my 6D. I am honestly not too excited about it when it comes to sharpness.

 

[crasher8]

Believe it or not I just returned a 135 f/2. Bad copy, soft. Turns out I'm not the only one this has happened to. I Gogled it.

I also have returned 2 17-40's. I take that back, I sold one and returned the other. I have an outstanding 24-105, 100 Macro , 40 pancake and 50 1.4. An UWA zoom for me is the toughest decision I have ever made. I am tempted by budget to try for a better copy of a 17-40 but I can't take the soft corners any longer. The 16-35 isn't good enough to justify the price and I would pick up the Tokina 16-28 in a heartbeat if the front element was protected and took filters. What to do?

 

[rpt]

I'm a bit embarrassed to admit this, but I'm not even sure what to do to test a lens. I have had lenses I was frustrated with, but always assumed it was me. Can you all give me some guidance on how to test lenses? I do have two L lenses including a new 25-105 IS that I got with my 6D. I am honestly not too excited about it when it comes to sharpness.

http://www.canonrumors.com/tech-articles/how-to-test-a-lens/
Hope this helps