Resolution Tests

Canon 24-70mm f/2.8 II Resolution Tests

Published September 11, 2012

Here it is, only 6 months after announcement! The Canon 24-70mm f/2.8L II has finally arrived.

I’d love to say something like: “Never have so many forums contained so many threads containing such strong opinions from people who’ve never touched a lens.” But that would be silly. It happens just about every time a new lens is released.

Depending on whose opinion you read, the new lens is either the sharpest zoom every made or an overpriced piece of junk that nobody should buy. It’s been trashed for its price, for not having image stabilization, and for its filter thread size. Posted images made with it have been praised as sharper than primes and condemned as no better than its predecessor.

I can’t say I’m thrilled with the Mk II’s price, but the original Canon 24-70 could certainly be improved on. The original is a good lens, but not up to the standards of, say the Canon 70-200 f2/8 IS II. It definitely has some reliability issues and a lot of copy-to-copy variation, at least some of which relate to its design.

On the other hand, the Tamron 24-70 provides the image stabilization so many people want, but it’s beginning to show some reliability issues, too. Still, it’s $1,300 and has image stabilization. The new Canon is a breathtaking $2,300. For that kind of money it better have world-beating performance. Heck, for that kind of money it ought to carry my camera bag, frame the shots, and do the post-processing for me.

The Usual Disclaimer

This isn’t a lens review. I am not a reviewer. I don’t spend days evaluating a single copy of a lens for all of its traits and characteristics, nor do I take hundreds of really great photos with it and describe how it works in the field.

What I do is test multiple copies of the lens for resolution and other basic stuff. I think that is particularly important with this lens, as its predecessor has, perhaps, more copy-to-copy variation than any high-quality lens I know of.

 A Quick Comparison

Looking from the side, the old and new lenses aren’t hugely different. The new one is a bit shorter.

 From the front, the larger 82mm filter ring is apparent.

They extend a similar amount but the Mk II is extended when shooting at 70mm, like most lenses, while the old one extends to shoot at 24mm.

With hoods mounted you don’t notice the old version extend, since the hood is fixed and the barrel extends inside of it.

At 1.77 pounds, the 24-70 f.28 II is not a lightweight, but it is a bit lighter than the original 24-70’s 2.1 pounds.

Resolution Results

We measured 5 copies of the 24-70mm f/2.8 II at 24mm and 70mm. For purposes of comparison I’ll add the numbers we know from multiple tests of the original Canon 24-70 f/2.8 and Tamron 24-70 f/2.8. Since the sharpest Canon zoom we have at 70mm is the 70-200 f/28 IS II lens, I’ll add its numbers at 70mm. Just to make it really interesting, I’ll also add our sharpest 24mm lens, the Canon TS-E 24mm f/3.5L II (but remember, we’re comparing it at f/3.5 to the 24-70 at f/2.8).

Lens24mm Ctr24mm Avg70mm Ctr70mm Avg
Canon 24-70 f/2.8 II954831950809
Canon 24-70 f/2.8730605705570
Tamron 24-70 f/2.8 VC815765735655
Canon 70-200 f/2.8 IS IIxxxx885765
Canon24 f/3.5 TS-E915775xxxx

We also checked distortion at both ends. The Mk II has 2.45% barrel distortion at the wide end, 1.34% pincushion at the long end. The 70mm pincushion is exactly the same as the version I lens, while the barrel distortion at 24mm is slightly worse than the original’s 2.15%.

This is short, sweet, and simple. The resolution absolutely, positively kicks butt and takes names. It is way better than the lens it replaces. It’s better at 70mm than the best Canon zoom I know of, the 70-200 f/2.8 IS II. It’s even better at 24mm than the sharpest 24mm prime we have, the Canon 24 TS-E. In the center, in the corners, it doesn’t care. We only had 5 copies to test, but they were all very similar with little copy-to-copy variation.

Resolution is not everything, of course. But it’s certainly an important thing. Unless the real lens reviewers find some dramatic problems with this lens, I’d have to lean towards worth-the-money on this one. I can’t believe I’m saying that a $2,300 standard zoom is worth the money.  But then again, I can’t believe I’m seeing a zoom lens out resolve a $2,000 world-class prime, either.

Roger Cicala

September, 2012

Author: Roger Cicala

I’m Roger and I am the founder of Hailed as one of the optic nerds here, I enjoy shooting collimated light through 30X microscope objectives in my spare time. When I do take real pictures I like using something different: a Medium format, or Pentax K1, or a Sony RX1R.

Posted in Resolution Tests
  • I returned the lens to Canon Uk and they told me it was within Canons Spec’
    It might be sharper in the centre than my old mk 1,but flare,distortion and vignetting are worse.
    Thanks again for you help though.

  • Hi Roger,
    I’m getting awful flare, even when the sun is not in the frame and quite high.Its not even attractive flare.

    Is there any thing that can be done apart from trying to shield it?



  • Thanks Roger for all your help.
    Ill get In touch with Canon Uk. Mind you after my last experience with them I won’t hold my breath. It took them 3 attempts to calibrate my bodies/ lenses. So I’m not sure…Can I ship it over to you guys….

  • Roger Cicala


    It certainly can be. Canon can adjust them back to where they should be. Just be specific where the problem is – which focal lengths, what part of the lens at what aperture, etc.

  • Hi Roger,
    Last question, promise.
    My copy isn’t, so can it be brought up to spec ?

  • Roger Cicala

    Andy, at f/5.6 it should. At f/8 it would be very close. The sides should be at least as sharp as the center.

  • Sorry Roger, I don’t think I was very clear in my previous question. What I meant to ask, should at f8 or 5.6 (50mm) give you the same sharpness at the centre edge (left & right) as in the middle of the frame?
    Thanks again,

  • Roger Cicala

    One thing I will note is the 24-70 II is going to be softer in the center at f/8 than at f/5.6. It is at maximum sharpness at f/4. After that diffraction, while mild, is definitely going to be present. That’s unusual to see at this aperture but most lenses are getting sharper stopped down and that more than offsets diffraction. The 24-70 II is not getting sharper stopped down past f/4 so all you see is the diffraction, at least in the center.

  • Thanks for the reply Roger.
    I thought not also.
    I picked up another copy today and it is a lttle better across the frame, but still not as sharp as the centre @ f8.
    With the second copy, colour moire is stronger and also red CA on the chart I am using for testing. Sorry to ask, but is this normal? In a way I hope so, as I don’t think the shop will let me have another copy. I wish I could send you a sample to look at.

  • Roger Cicala

    Andy, definitely not. Sounds like it may be a decentered copy. It should be tack sharp across the frame.

  • Hi Roger,

    I’m finding with my copy that even at f8 a little soft towards centre edge of frame when taking full lengh portraits @ 50 mm.
    The body will be pin sharp but the face is definitely a little soft, even using live view to focus on the face.
    Should this be the case?

  • Roger Cicala

    Michael, it sounds like you may have a decentered copy. The lens should be better than what you describe.

  • michael

    Hello , i got that lens a week ago.I noticed softness issue on the right side of the images ( corners up and down ) at 24mm and 35mm from F2.8 – F4. The left corner is not that bad but the right is a little bit softer. I compared my 24-70 2.8 ll with the 70-200 2.8 ll at 70mm and to be honest im very impressive. I found that 24-70 ll is little bit sharper at 2.8 in the center and in the corners. At F4 they are very similar even in the corners. Why there is softness? probably this lens produce sharp images from edge to edge?

  • John M

    A lot of people have noted that the original lens barrel extended as the focal length decreased, backwards from what we’re used to. Maybe I’m missing something, but with the hood fixed, this is as it should be if you want the hood to function at both 24mm and 70mm. At 24mm, the barrel is closest to the front of the hood so the tulip edges allow a wide field-of-view. At 70mm, with the barrel fully retracted, the hood now allows a smaller FOV which is correct if you’re trying to minimize the effect of light sources out of the FOV.

    The Mk II lens hood attaches to the barrel. If we assume that the hood is designed to be tight at the 24mm setting (just barely out of the FOV, causing minimal vignetting), then at 70mm the hood does nothing but act as a bumper to protect your lens. It certainly won’t do much to prevent haze from strong side sources.

  • lisa

    I also want to know how the operation work? did anyone answer doc searls??

  • Another difference: zoom operates in the normal way, becoming longer toward 70 and shorter toward 24. The old lens worked the opposite way, and drove me nuts.

    I’m renting one of Roger’s new lenses right now and loving it.

  • Bob B.

    Roger…you do a GREAT job and I TRULY respect your information because you qualify everything you say with solid logical information an intelligent references that have meaning. Plus all of your experience. The other thing is…you generally never take yourself all that seriously and you are open to all info and opinions, but you can still stand your ground when you believe in something.

  • Roger Cicala

    Eric, all of our measurements are ‘best cener focus’ based. So field curvature would make the corners appear softer than they are.
    There’s no ‘right’ way to do it, we feel this is most like real world.

  • Eric Meola

    As most wide angle lenses (and the 24-70mm II at 24mm is not an exception) have a significant amount of curvature of field, how do you determine edge resolution figures that you feel are accurate ? In other words, if you are testing a telephoto lens, photographing a flat field is relatively more reliable in terms of measuring resolution out from the center. But when a lens has significant field curvature, how can you come up with numbers that accurately indicate sharpness away from the center?

  • Jarj

    I have owned the 28-70 f2.8, the original 24-70 f2.8, the 24-105 f4 and now the 24-70f2.8 II. I am not a professional reviewer or a dealer and I get nothing whatsoever from Canon. All of the equipment I own I buy retail preferably from my local dealer. The new 24-70 f2.8 II is an exceptional lens. The first 24-70 was a great lens which good detail, colors, contrast, etc. The 24-105 f4 was also a great lens, slower but longer and with IS. The detail on the 24-105 was crisper compared to the 24-70 I but ultimately I preferred Leica and Zeiss rangefinder lenses. I eventually decided the Leica and Zeiss lenses were better because the detail was real, not computer generated. The new Canon 24-70 f2.8 II is closer to the Leica and Zeiss lenses. The image straight out of the camera is close to great without any post processing and I only sharpen about half of what I did with the earlier lenses. More importantly everything is sharp, not just the edges of lines and the image seems more real, almost three dimensional. Now the only reason to own a fast prime is to get shallower depth of field.

  • Gerd

    Thanks for the Info. It really helps to make a decision.
    For my opinon resolution is one of the major issues for crisp images.
    It brings it closer to apo correction, white shows white and black shows black.

  • Clyde

    Much thanks for the info. Your approach certainly inspires confidence to give one a sense of having a grasp of the overall significance of this lens release. Do you think it is at all likely that Canon will do an upgrade of the 90mm t/s anytime soon? If you have it available, I would really appreciate having the resolution figures of the present version of the 90 t/s as well.


  • Scorpius

    BTW.. Many thanks for posting this Roger…

  • Scorpius

    Looks like an amazing piece of glass,loving the fact that its lighter too.. hopefully the 85mm 1.2L will get this treatment soon.. it’s fab but a monster in weight.

  • Roger Cicala


    Hopefully next week. I’ve gotten some good information but I have to find out whether I can quote my resources or not.

  • Kai


    Any chance you will have time to follow up on your promise from Sept 11 2:27pm, on getting focus accuracy data up in a new article?

    Thanks, Kai

  • Roger Cicala

    Hi Michael,

    I think there probably is some truth to the more experienced photogs with better cameras tending to have the 24-70 Mk II right now. On the other hand I do think the Canon II is the sharpest lens. I can’t comment much about bokeh, I just don’t evaluate that.

    I see the Tamron as a very good compromise lens: not quite the sharpness (or range, it’s not as long) and a bit more distortion. But it does have IS and it’s sharper than the original Canon, which makes it a very nice option.

    I think the Canon II is the better lens, but I wouldn’t go so far as to say it’s worth the price difference. You can buy a decent prime lens and the Tamron for the same money as the Canon.

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