Bad copies of a 24-70

Well, I just spent the better part of the day at Henry's (a large camera chain in Canada) testing all 4 24-70 2.8 lenses they had to try and find a good copy. I got one for Christmas and took almost 400 shots with it over 4 days. The colour and contrast were amazing, but the focus was not what I expected. I am new to photograpy and this is my first lense purchase after the kit lens, so I wasn't sure what to expect from "L" glass.....but I expected more. I finally had a day without my 4 year old and decided to take it up and have someone who new what they were doing take some shots and view them. Man were they bad. He said he never seen one that was that far off (back focusing). He opened a new lens, it was better, but not great. In the end we went through 4 lenses before we had one that to him was acceptable. I exchanged it for my lens and will play with it over the next week or so. I guess my question would be "is this normal?" If it is, I can't believe that with this quality lens there are so many duds out there.

I believe it is normal, although many will argue that lens variation is a wild myth perpetuated by people who don't know how to use their equipment.

Variation seems to, err, vary, somewhat from maker to maker and model to model. From what I've read the 24-70 is one of Canon's less consistent lenses.

Did you try this focus tests on different bodies and other lenses which were known to have "good" AF? How do you know that perhaps your camera is misadjusted, and now you own the only misadjusted 24-70 in the store?

I have one on order so you must be wrong! (right??)

Rob.
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shoot!

Mike K said:

How do you know that perhaps
your camera is misadjusted, and now you own the only misadjusted
24-70 in the store?

Click to expand...

Presumably she has other lenses that work properly.

See my thread from a few days ago about a post Christmas present. I have a new one on the way, with the first copy going back...

http://forums.dpreview.com/forums/read.asp?forum=1029&message=16539465

I described my findings to Canon who themselves called it "defective". I don't know if it was defective or just not calibrated at all (still not sure what steps are actually taken in build process). Mine wouldn't focus on any number of targets at f2.8 no matter what. Wasn't the 20D, as that was recently calibrated, and shots with my venerable good old walk around 28-135 IS and 70-200 2.8 IS are tack sharp, as is 50mm MK1. Mine was horrific, there are no other words to describe it. It wasn't the optics, as I could manually focus and get tack sharp, but AF at f2.8 especially in the 24-50mm range was awful..

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Jay S.
Fuji 7000 / Canon 20D
http://jaysott.smugmug.com
http://www.pbase.com/jay_s

Yes, I myself was sceptical of the "bad copy" myth regarding the 24-70, until unfortunately I experienced it myself.

My first copy was so out of focus that it was much worse than my 18-55 kit lens, so it went back to the dealer immediately.

My second copy seemed much better, but over time I came to realize that wide open at the wide end (24-35 or so) it was much softer on the left hand side than on the right hand side.

I took it to Irvine to have it serviced. It came back much better, and at first I thought it was ok. It certainly was much better at the wide end.

However, I have now noticed that around 50mm and at large subject distances (> 10m) it is still too soft on the left hand side. I might have accepted the results if it had been a $100 consumer lens, but not for a $1000+ lens.

So, now it's at Canon Irvine for the second time. Hopefully, they'll get it right this time.

I tried to get them to comment on the greater copy-to-copy variation of the 24-70, compared to say the 70-200 lenses, but didn't get much of a response from them.

However, it does seem to be well documented in various forums that the 24-70 has more of a quality control issue than other Canon lenses. I don't know whether it has to do with its unusual design (of being longest at the wide angle range).

I have not had any front or back focussing issues with it. "Just" the softness on the left side.

--
'Great meal. What pots did you use?' -- Petteri

Wolfgang Bluhm
http://www.wbluhm.com/

that every maker has its problems with QC, whether sigmas 1850 or 2470, or tamron 2875, or canons 2470 or 70200. on balance i think each specific lens has MANY more good apples than bad, but QC issues are real for each maker.

--
http://www.pbase.com/fstopjojo/lenstests

“98% of all lenses are better than 100% of all photographers.” Michael Reichmann

Nice site and have viewed it for some of the test you've performed. So where do all the lenses come from?

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Jay S.
Fuji 7000 / Canon 20D
http://jaysott.smugmug.com
http://www.pbase.com/jay_s

That lens was a problem child when it came to working on the 10D (and it was the lens, not the body). I don't know what to say, Canon makes good stuff most of the time and on occasion some bad stuff.

I went through four 50mm f/1.4 lenses (drove all over Phoenix, AZ) before finding one that would work on both an EOS-3 and 10D; they would focus WAY past infinity (so bad even a blind person could pick it out just by looking in the viewfinder). So, I'm not surprised you have now discovered a bunch of bad 24-70 lenses in a short period of time.

I do have good news for you (and you don't have to buy Geico Insurance). If you call Canon and ask to talk to a supervisor (you must get past their front line of defense) he will send you a free shipper and you can have your new lens calibrated properly. Just tell them you got the best of the bunch and it still isn't good enough for your purposes.

Regards,

Joe Kurkjian, Pbase Supporter

http://www.pbase.com/jkurkjia



SEARCHING FOR A BETTER SELF PORTRAIT

We were actually using the stores body while we tested all the lenses....

Thanks, I think I will do that. I have only been able to take a few shots with the new lens and MAN what a difference!.
Thanks!

I had what I thought was a similar experience. The EF 24-70 f/2.8L on the hands of an amateur is a formidable lens. You had a "kit" lens and weight and the overall feel of the lens is very different. It took me a while to get used to my copy but now, I'm completely loving it. You have to take photos from f/2.8 to f/22 at all focal lengths. That's a good way to famililarize yourself. Secondly, use a tripod- a lot of 'blur' can come from camera shake. Good luck!
--
'You see, but you do not observe' Arthur Conan Doyle

What is causing the problem if top tier lenses can't focus sharply all the time? How long is this going to go on?

While reading the rest of this thread I imagined an experiment of monkeys left alone in a room with carts of lens subassemblies. They were expected to complete some assemblies after a few hours, but only played bumper carts while knocking the sub assemblies to the floor. I don't know what else to think, except I don't feel like buying any lenses when I read this stuff.

A K said:

That lens was a problem child when it came to working on the 10D
(and it was the lens, not the body). I don't know what to say,
Canon makes good stuff most of the time and on occasion some bad
stuff.

I went through four 50mm f/1.4 lenses (drove all over Phoenix, AZ)
before finding one that would work on both an EOS-3 and 10D; they
would focus WAY past infinity (so bad even a blind person could
pick it out just by looking in the viewfinder). So, I'm not
surprised you have now discovered a bunch of bad 24-70 lenses in a
short period of time.

I do have good news for you (and you don't have to buy Geico
Insurance). If you call Canon and ask to talk to a supervisor (you
must get past their front line of defense) he will send you a free
shipper and you can have your new lens calibrated properly. Just
tell them you got the best of the bunch and it still isn't good
enough for your purposes.

Regards,

Joe Kurkjian, Pbase Supporter

http://www.pbase.com/jkurkjia



SEARCHING FOR A BETTER SELF PORTRAIT

Click to expand...

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Torch

Should it be as sharp as other prime at f2.8?

I am happy with my 2470 for f4.0 and above (yes as sharp as other primes). Canon at Irvine caliberates it once, not much difference. I thought a zoom lense at wide open hardly can compete with a prime lense, I thought that's the general rule. Should I expect more form a L lense? Thanks.

my second 24-70 (the one I finally kept after the nightmare I had with my first one...) is good from f/4-16. 2.8 and 22 are not acceptably sharp.

good luck/

I tried two copies of this lens, months apart. Neither would perform on my 20D. I got more OFF shots than I care to share. At any rate, the weight to performance ratio just didn't pay off for me.

l lug a 70-200L 2.8 around often and I don't complain because the images just can't be beat. If you want the 24-70, just keep trying copies until you get it right. I've seen some stunning images from that lens.

"NT" means no text.

Joe Kurkjian, Pbase Supporter

http://www.pbase.com/jkurkjia



SEARCHING FOR A BETTER SELF PORTRAIT

Rends,

I ran all my tests on a tripod with a cable release and shutter speeds far exceeding the shutter speed to focal length ration. The focus wouldn't work at 2.8.. but I could manually focus the same image. Repeated in numerous situaitons for testing, indoors and out. Somethings are just not user error. That said, it is a handful of lens, and the weight is nothing to ignore. At f2.8 though, and say 1/400th of a second at a distance where the depth of field is more than 1/2 inch, the image should be in focus

Rends said:

I had what I thought was a similar experience. The EF 24-70 f/2.8L
on the hands of an amateur is a formidable lens. You had a "kit"
lens and weight and the overall feel of the lens is very different.
It took me a while to get used to my copy but now, I'm completely
loving it. You have to take photos from f/2.8 to f/22 at all focal
lengths. That's a good way to famililarize yourself. Secondly,
use a tripod- a lot of 'blur' can come from camera shake. Good
luck!
--
'You see, but you do not observe' Arthur Conan Doyle

Click to expand...

--
Jay S.
Fuji 7000 / Canon 20D
http://jaysott.smugmug.com
http://www.pbase.com/jay_s

Mine worked perfectly right out of the box. I expected it to be a bit off at the extremes but it is not. I'm shooting on a MkIIN and a 20D.

Actually, there is a tendency for the collective Internet to overstate quality and performance problems for all things, not just camera equipment. People that are dissatisfied with their lens, body, widget, what have you are a lot more vocal about it, and a lot more likely to post their experiences than those of us that are perfectly satisfied. Canon doesn't make things that don't sell (don't work maybe, but not don't sell). They must be moving off the shelf or Canon would have stopped making them by now. I can't help but believe that me and my two pro co-workers that love theirs must be the rule rather than the exception. Good luck!
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BBQBluesStringer