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Quick Tamron 24-70 MTF Data

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We got a couple of Tamron 24-70 f/2.8 VC in Canon mount today and I was able to compare them, very briefly, with the Canon 24-70 f/2.8 L.

The Tamron is not quite the range of the Canon on the long end, clearly a few mm shorter than Canon (which is clearly a couple of mm short of 70mm). For anyone who doesn't know, manufacturers "round" up or down to give the numbers they actually put on the zoom. I can't see where being a bit shorter is going to affect anyone very much.

Autofocus is reasonably fast, although the Canon may be a bit quicker. Nothing dramatic like the Tamron 70-300 (which was horribly slow), though. Again, I can't see this making a ton of difference to anyone.

Imatest results were clearly in favor of the Tamron, though, at both the long and short ends. I was able to run 3 copies of the Tamron on 2 cameras and results were as consistent as we'd like them to be.

These are MTF 50 results (3 copies of each lens tested, best results of each copy averaged, variation +/- 2.5%) measured in line pairs / Image height on 5D Mk II test cameras from unsharpened raw files.  Ctr = the Center Point, Avg =  a weighted average at 13 points on the lens (center, 4 mid 1/3, 4 corners, top and bottom) The Tamron is clearly better on the wide end, particularly in the average number across the entire lens. At 70mm the centers are about the same (you couldn't see that difference, even in reasonably sized prints), but the average across the lens is again better with the Tammie

 


Canon Tamron
24mm Ctr 730 815
24mm Avg 605 765
70mm Ctr 705 735
70mm Avg 570 655

The Lens sharpens up even further at f/4, and a bit more, particularly in the corners at f/5.6 as shown in the graph below.

 

MTF 50 improves to f/4 in the center and f/5.6 in the corners.

So what does this all mean? It means the lens has potential to be good. We'll have to wait until some real world results and reputable reviews come in to get some real-world initial impressions.

 

 

 

21 Responses to “Quick Tamron 24-70 MTF Data”

Bob said:

Interesting stuff, especially since the Tamron has the extra Vibration Compensation glass elements inside.

As you said in your "Limits of Variation" article, the Canon 24-70 performance tends to deteriorate as the plastic screw collars wear out. Are the Canon 24-70 numbers you posted here from a group of recently-serviced lenses, or are they just three random lenses off of the shelf?

Brian said:

Thanks for the quick data point on this lens! How do those numbers compare to the Nikon 24-70? Debating whether or not to pre-order the Nikon mount version.

LensRentals Employee

Roger Cicala said:

Brian, these numbers are a little better than the Nikon 24-70, but being shot on different cameras makes a difference. I would not recommend translating Tamron for Canon results to Tamron for Nikon results. Could be the Nikon numbers are a bit better or worse.

Roger

LensRentals Employee

Roger Cicala said:

Bob, the Canon numbers are from lenses in our good data grouping - as you saw in that article we service anything not up to spec.

Benjamin Anderson said:

Looks like a nice potential alternative. It'll be interesting to compare it to the new Canon 24-70mm f/2.8L II when you can get your hands on it. Especially since it's $100 cheaper than the current L's street price and $1000 less that the II.

Though, it also has a 82mm filter diameter. It probably end up being cheaper to get the L, if you already have decent 77mm filters, and need them. Or even if you don't own them already...

Roger said:

I think it's fine even if it doesn't compare incredibly well to the Canon 24-70mm II. I think for many of us, the original Canon 24-70mm is still a lot of cash with only sub-par (at least wide open, and field curvature issues) performance. Why i sold it time and time again. This tammy could find itself in a nice price point for many - same price as the original Canon but better performance (let's hope, it's again too early to tell). That to me means VALUE and perhaps "good enough"performance to be content with. It may be easier to swallow $2300 for the new canon lens given the original's quirks. but with this lens thrown in, with image stabilization, the game is different. Right on Tamron - i hope it's a nice piece of glass.

Vikta said:

All this is interesting especially for others like me looking for f2.8 constants in this range with stabilization. I already orderd mine and will receive it tomorrow. I will be testing my copy on a 5Dmk3, later to leave first impressions on YouTube (vikta11). I have high hopes for this model since I'm personally having great satisfaction with f2.8 constants having stabilization compared to faster primes with out. I shoot in low light over 50 percent of the time and usually moving subjects like people. My 35mm f1.4L doesn't keep up with Canons 100mm f2.8L, 70-200 f2.8L ii and Sigmas 17-50 f2.8 DC. I love primes and they have there place, just the stabilization is the only systems able to keep up with moving subject in low light with out cranking the ISO to 3200 and above.

Scott McLeod said:

Thanks for this Roger! I am breathing a sigh of relief :) as this could be the FF walk-around lens I've been waiting for - I might hold off on the 28/2.8IS for a while. I look forward to seeing how it shapes up in other areas. For a lot of what I like to shoot, a high-quality stabilized zoom is invaluable, which is why I need an APS-C cam as well. I passed on the original 24-70L precisely because of the field curvature issues, but for the price of the LII it'd better be the best zoom ever made (and still no IS...)

Alternately it could resuscitate my D700 which is very "easy" on lenses. Either way it's great to see some real competition for the OEM FF standard zooms - with stabilization to boot!

Larry said:

Roger: Thanks for the quick review. This lens was not on my radar screen until very recently. I am about to take a trip to a rainforest. I'm looking for a lens to fit between a Canon 10-22 and a 100-400 on a 7D (1.6x crop) camera. I have the 10-22 and the 17-55/2.8. I am also considering leaving the 17-55 at home to take a 24-105/4; better range, slower aperture. If it's OK, I have a few questions:
1) You said that in reality, it is a few mm short of 70. Can you guess how short? If it's only 60mm, it gives me essentially nothing over the 17-55.
2) Any idea how the Tamron would do on a crop camera? I understand it would be 38mm eq at its widest.
3) Given it's non-EF-S mount, I could theoretically add the Kenko Pro 1.4x TC to it to get me a 70-100mm/4 range. Any guess on performance with the TC?
4) I am guessing that using an 82-77mm step-down ring would be no problem considering the 1.6x crop. Do you agree?

LensRentals Employee

Roger Cicala said:

Hi Larry,
I think the Tammie is about 64mm at the long end, since we measured the Canon 24-70 at 67mm at the long end and it's clearly a bit shorter than that. But remember the 17-55 isn't 55mm either, it's 53mm. The Tammie should be great on a crop camera since the biggest issue for some people seems to be vignetting on a full frame which won't be a problem. As to a TC, I could only guess, but I'd guess OK to poor. TCs just don't work very well on standard range zooms. I don't know about the step down ring, either, going down is always risky. It might work.

Roger

Eric said:

There is also a nice review at ephotozine. com- using the same Canon 5Dmk2.
I have already preordered my copy for Nikon D4.
Im eagerly waiting for mid june to get my lens.
I guess Tamron will be on par with the Nikon 24-70mm 2,8 plus having vibration compensation.
I had earlier the Tamron 28-75 f2,8 in D700 and it gave good results,but it seems that the new one is really better.

Ralph Conway said:

Thank you, Roger. That gives me some hope to have a chance to get a 24-70 WITH IS at the end.

Ralph

George said:

While the 24-70 VC seems to be an optically decent lens, I will not buy another lens from Tamron, Sigma or Tokina, until these guys finally get Zoom- and Focus-rings turning the right way round for Canon.

It is absolutely ridiculous they got away with this evil practice for so long. Canon-users deserve to be taken as serious as Nikon/Sony users. All that is required is one different cog-wheel in the gear box for focus and zoom-ring. So get to work, Tamron!

Larry said:

Roger, thanks for the quick feedback. I figured a TC would not be a good idea. As for the step-down ring, I've been pleasantly surprised sometimes. For instance, I routinely use a 67-58mm SD ring on the Canon 100L macro with a 1.6x crop camera. More amazingly, I took a chance that the Sigma 30mm/1.4 had to be designed to cover Nikon's 1.5x image circle -- it turns out it takes a 62-58mm SD ring just fine on a Canon 1.6x crop. Of course, the wider you go, the more risky it is. Thanks again, Larry.

Jon said:

I just received my copy of the Nikon version, seems fairly similar to the Nikon 24-70 but a little wider with more barrel distortion at 24 and slightly more vignetting. Very sharp with and without VC. It definitely helps video stability. Stills at 1/20 are way sharper with VC.
My question/issue is that I noticed that when zoomed to 70 with the barrel extended, if you look at the end that attaches to the camera, a lot of circuitry is exposed around the optics. Could any dust, debris, etc. fall out of this area and into the sensor of my new D4 during heavy use? All my Nikon lenses are sealed where they attach to the camera. I read your article on evaluating new lenses which is what got me to take a critical look at it. Is this a design issue worth worrying about? Thanks.

LensRentals Employee

Roger Cicala said:

Hi Jon,

A lot of lenses are like that. Dust and debris are going to get into any lens, even the ones that are weather sealed eventually. I hadn't thought about whether it could fall down on your sensor. It certainly could, but I'm not certain it's much more likely to make your sensor dirty than any other lens. Like lenses, sensors are all going to get dirty eventually.

Roger

Sotir Popovski said:

Hi Roger,

Thank you for testing this lens. As I live in Australia, I couldn't rent this lens and see how it performs on my 5d m2 so I decided to buy it instead. I don't have any previous experience with 24-70 lenses so I don't know what to expect from it. As you are a professional I would like your opinion if you have the time.
I did two tests. One is the newspaper test, and the other is a quadrant test to check if the lens is centered.
I have the newspaper test in RAW here: http://www.mediafire.com/download.php?sli3l6a82g20mkk (30MB size)
Same image converted to JPEG with Canon's software. Sharpening +5 Contrast +1 the rest of the parameters are set to default.
http://www.mediafire.com/view/?3sk3x3gbxf58gif (20MB size)
If you are short on bandwidth, here are the crops and centering test:
http://www.flickr.com/photos/22285064@N03/sets/72157630580733610/
I would highly regard your opinion, as I would like to know if I should keep this lens or return it...Or even send it back to Tamron to have it fixed. What is your say on this? Thank you in advance.

LensRentals Employee

Roger Cicala said:

Hi Sotir,

In looking at your images it appears they aren't perfectly square - it looks like the lens was tilted compared to the paper. I can't really tell anything of significance from them.

Regards,

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