EF 24-70 MkII: Erratic performance

To the OP and other people that don't rate the mk2, you are up against a lot of people that are happy with their mk2's with some saying it has prime lens qualities.

EVERYBODY has their view whether we choose to like it or not, if you have a great example GREAT, keep it treasure it!! if not send it back or buy something else but prepared people on here do not like a bad word said about it!!

My view is its not so great for the money involved that's why I haven't bought it, seems a few others are not too impressed either...

I think it may well be a GREAT lens IF you get a good copy but there in lies the problem, it seems Canon QC let too many sub standard lenses through the net leading to conflicting reports.

Also in recent times we have been spoilt with the 70-200 mk2 performance and I think we expect the same from the 24-70 mk2 especially with that price tag compared to the mk1.

Oh, the trade show comment was aimed at me as I tried out several copies of the mk2 at a national show and didn't rate it, since then I have learnt that you cannot judge lens performance under artificial light or even what your own eyes tell you, you have to buy a lens on the grounds of all positive comments and reviews - or so I was told

Charlie wrote in post #15953077
I do think you're putting the chicken before the egg. 100 real world shots and 200 test shots seems backwards to me.

before I do test my cameras, I put them through the ringer with a lot of shots over different days. If you shoot as you normally do and have little issues, then no need to run test shots. Also, it might be a good idea to invest in Focal or something, to automate the process and take out human errors in testing procedures.

good luck with your findings.

I don't understand this comment. The OP did a walkabout of everyday usage and found a tremendous number of shots were mis-focused:

So then, being a good scientist/engineer, the OP performed a bunch of repeatable tests using a fairly standard test set-up. And confirmed his suspicions that the focusing behavior was erratic (non-repeatable for a given specific condition) and variable (front and back focused seemingly uncorrelated with any particular lens setting).

The same tests with the same camera body and other lenses did not exhibit the same erratic variability.

The OP came to a fairly sane conclusion (IMHO) that this particular copy of the lens is bad. What the OP would like to hear is whether there have been a larger-than-normal number of bad copies of this lens, or is the extremely rare? If a lot of bad copies, the OP was strongly considering returning the lens (rather than exchanging) and trying something else.

There were far too many negative-to-the-OP posts in this thread for this type of forum. We're supposed to be supportive of posters with issues, trying to help them solve their problem. Instead "we" are telling them the test rig was wrong (it wasn't), or that they aren't testing correctly (live view vs viewfinder, which had no reported difference), and that they should do more real-world tests and stay out of the lab until they are certain the lens is crap (seemed like a pretty easy conclusion to make after that first day, didn't need days and days of real world shots).

We could have approached this far better, even while making the same points overall (although I still think the questioning of technique was unwarranted):

"Hey OP, did you try Live View as well as through the viewfinder?"

"Hey OP, where do you focus the camera on that test rig? It looks like a simple tilted piece of paper to me."

"Hey OP, your tests don't mention anything about edge-to-edge focus. Did you try taking a photo of a flat textured wall parallel to the sensor to see if there is variability across the frame?"

Instead we get responses that assume the OP "did it wrong" and sniping about trade-show tests (which wasn't even the OP).

Yeesh.

This is just a lens, folks, not a religion or your children. It can be returned if deemed defective for the slightest reason.

And if not defective or the defect is easily fixed by Canon, then the OP has generated a future Canon Refurb Shop sale...

shinksma

...and that about says it all... Thank you Shinksma!...

When you get 3 photos of the same flower front focused, back focused and indifferently focused from 3 ft away, you know that it's either your technique, or the lens... Thus I chose to remove the technique question, although, I believe, I know my camera and its capabilities quite well.

If I can shoot these handheld (ok with IS, but at some tele length...)

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^^ super bad front focus. Doubt MFA would even fix if that far off.

Charlie wrote in post #15953464
^^ super bad front focus. Doubt MFA would even fix if that far off.

Yep! Shot at FL=41mm

Now compare this to this...

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I think you have a bad copy. I've not had any issues with mine. Haven't really used my 35L since getting this lens.

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You got a turkey to shoot!...

But then, so did I...

I hope that the next one is going to be better...

Still seems to be a bad copy to me. My 24-70mkii is one of my most reliable lens in regards to auto focus reliability. On a related note, I had a Sigma 50mm that had erratic AF and it had to do with the varying light conditions ( artificial lights vs outdoor, and red flowers vs blue flowers) . I sent it in to Sigma, and AF is great now. They did a firmware update and calibration but did not explain to me what was the problem.

MakisM1 wrote in post #15953410
If I can shoot these handheld (ok with IS, but at some tele length...)

I can't see any good reason for this:

If it consistently has this problem then I can't imagine that's how the lens is supposed to be. I would definitley return and try another. I wouldn't expect even an inexpensive kit lens to consistently miss focus as bad as you describe.

If you can clarify one thing. You said you tried Live View, but it wasn't clear if you had similar (or different?) focus problem when you did? If you had focus problems using LV and you tried it in decent light, then it's especially likely that something is wrong. LV tends to either miss focus because of lack of light or really lack of contrast, but it very rarely has only some front focus, for example. Instead it would usually be in focus or completely out of focus (might not be exactly the focus you want with thin DOF but it will choose something it is aimed at).

snake0ape wrote in post #15953677
Still seems to be a bad copy to me. My 24-70mkii is one of my most reliable lens in regards to auto focus reliability. On a related note, I had a Sigma 50mm that had erratic AF and it had to do with the varying light conditions ( artificial lights vs outdoor, and red flowers vs blue flowers) . I sent it in to Sigma, and AF is great now. They did a firmware update and calibration but did not explain to me what was the problem.

mine too. not saying there isn't something wrong with this lens but the attempts to knock the best medium range zoom made are pathetic, predictable and laughable .

ed rader wrote in post #15955418
mine too. not saying there isn't something wrong with this lens but the attempts to knock the best medium range zoom made are pathetic, predictable and laughable .

What is pathetic? Besides the lens that doesn't seem to do what it should?

Why do you feel the lens has to be defended? Especially if the lens is faulty?

What do you find pathetic about this story? Except the badly focused end results of that lens, that is?

clarnibass wrote in post #15955290
If it consistently has this problem then I can't imagine that's how the lens is supposed to be. I would definitley return and try another. I wouldn't expect even an inexpensive kit lens to consistently miss focus as bad as you describe.

If you can clarify one thing. You said you tried Live View, but it wasn't clear if you had similar (or different?) focus problem when you did? If you had focus problems using LV and you tried it in decent light, then it's especially likely that something is wrong. LV tends to either miss focus because of lack of light or really lack of contrast, but it very rarely has only some front focus, for example. Instead it would usually be in focus or completely out of focus (might not be exactly the focus you want with thin DOF but it will choose something it is aimed at).

The lens is on its way back since yesterday for an exchange. I hope that the next copy will prove more consistent.

The procedure with Live View which was recommended by the site which provided the target design required to focus manually until the confirmation chirp. The early results were all over the place, so I rationalized that by the time the confirmation beep was emitted, I might have turned the focus collar a fraction more. So, I went on Live View AF. The results were not any better, so I re-did a complete test matrix using the VF.

This is FL 35 mm at 60 in. Exif intact

pwm2 wrote in post #15955447
What is pathetic? Besides the lens that doesn't seem to do what it should?

Why do you feel the lens has to be defended? Especially if the lens is faulty?

What do you find pathetic about this story? Except the badly focused end results of that lens, that is?

that guys tend to shoot off at the mouth withpout knowing what they are talking about. sorta like you .

ed rader wrote in post #15955418
mine too. not saying there isn't something wrong with this lens but the attempts to knock the best medium range zoom made are pathetic, predictable and laughable .

Pathetic, not predictable and but very laughable is the quality of this OP's lens, Like ed if you have a mk2 performing as it should then I imagine you would defend it.

The issue is with Canon QC, if the OP had a great copy of the lens first time then i'm sure he would be here singing its praises and not putting it down...remember we generally only see one or two lenses before we purchase out of the thousands made, if yours is great then its the best all round standard lens if its bad then first impressions last and its hard to stump up $$$$ for something that is hit or miss..

So then you might tell what is wrong in this thread.

The only thing I have seen wrong is that the lens seem to be wrong. And a number of people seem to be busy defending the lens, not able to accept that sometimes a lens can be broken.

It's pathetic if people with problematic lenses will have to get them replaced in silence just to not get jumped.