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First Look: Zeiss CZ.2 70-200mm T2.9

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Ah, as if the 70-200 zoom field wasn't crowded enough, with each camera maker having one or four along with the Tamron 70-200 f/2.8 VC and the Sigma 70-200 f/2.8 OS, but Tyler decided we have to stock yet another one. So today I have to test yet another 70-200mm, the Zeiss 70-200 T2.9 CP.2.

 

One of these things is not like the others.

Comparing the Specs

The Zeiss is a bit pricier than the others lenses in this range, and a bit larger. But you get twice as many aperture blades for your money. Not to mention it has significantly more light transmission. Don't you wish photo lens makers had to use actual transmission (T) instead of theoretical calculations (f)? Looking at the table you kind of see why the camera makers might rather not.

Zeiss CP.2 Canon IS II Nikon VR II Tamron VC Sigma OS
Price$19,900.00$2,200.00$2,400.00$1,499.00$1,249.00
Weight (lb)6.23.33.43.23.15
Length (in)9.857.88.17.47.8
Aperture blades188999
Min. Foc Dist. (ft.)53.94.64.24.6
T#2.93.43.33.23.2

Ok, enough of the silliness. The Zeiss lens is clearly an entirely different beast and while we can mount it to our SLRs that's not what it's designed for. That extra money and weight go into making it a true cinema lens with long, smooth focus and zoom gearing. It's also really parfocal, meaning if you focus on something at 70mm and zoom out to 200mm the object is still in focus. None of the photo lenses are (although budget minded cinematographers desperately want them to be).

Just a Little Bit of Handling

I could go on for some time about how accurately it focuses (it does), how smoothly it zooms (totally true) or how it's not too heavy to hand hold for a while (a complete lie - it weighs almost as much as a Canon 500 f/4 IS II). This is a lens designed from the ground up to be mounted to a set of rails and focused with a geared follow focus system. It's perfect for that and built as solidly as any cinema lens we carry.

Cinema lenses, as a rule, are designed differently than photo lenses. Photo lenses are about rapid autofocus, which means rear or inner focusing. That in turn means focus breathing, often to the point of massive changes in focal length when you focus closely. Being parfocal is of little importance for a rapidly autofocusing photo lens. When you zoom from 80 to 150mm if the camera can autofocus in a split second, who cares if it's still in focus after the move? Not to mention the subject might be moving anyway. Being parfocal is very important for a cinema zoom.

We did a quick parfocal check, comparing it with the Canon 70-200 f/2.8 IS II, which is not parfocal (but actually sort of close to it). We simply set the lenses at 70mm and live view focused on the bush in the center with each lens.

 

Then zoomed to 200mm and took another image.

Here are 100% crops of the bush at 200mm with the Zeiss on the left, Canon on the right.

100% crops at 200mm after focusing at 70mm. As expected, the Zeiss (left) is parfocal, but not the Canon (right).

 

We did a quick check for focus breathing, too. I won't repeat the Canon lens, it breathes significantly and the focal length changes as you zoom close. The Zeiss 70-200 did not focus breath significantly from far to near focusing.

Yes, I Had to Run the Numbers

Absolute resolution, historically, has been far more important for a photo lens sitting in front of a high-resolution sensor than a video lens. Even 4K video is about 8 megapixels, not nearly as resolution sensitive as a 36 megapixel SLR. So when we've tested video lenses for resolution compared to photo lenses they've historically not held up well. Resolution isn't their primary focus.

But we thought we'd see if the Zeiss could hold its own against the best 70-200 f2.8 photo zoom we have, the Canon 70-200 f/2.8 IS II. Because the Canon is actually shooting at T3.4, we tested the Zeiss wide open (T2.9) and also stopped down slightly to T4. I'm not going to clutter up the tables with the T4 numbers - this lens is as sharp wide open as it is stopped down, with the exception that the corners get just a tiny bit better at T4.

These are Imatest MTF50 results using a Canon 5D II test camera showing point sharpness at the center, average over the entire lens, and average of the 4 corners.

Center MTF50 Avg. MTF50 Avg. Corner MTF50
Zeiss@ 70mm990775600
Zeiss@ 135mm915675575
Zeiss@ 200mm815575425
Canon@ 70mm875755575
Canon @ 200mm840720525

Well, as you can see from the table, the Zeiss 70-200 T2.9 takes the idea of video lenses being lower resolution and shows that at the right price point, you really do get it all. At 70mm it's clearly outresolving the Canon 70-200 f/2.8 IS II. The MTF50 decreases steadily at longer zoom lengths, but even at 200mm it's still as sharp in the center as the Canon, which is the highest resolving 70-200 zoom we've tested. And remember the Canon is working at T3.4 wide open, a half stop slower than the Zeiss.

Let's keep some perspective - if I were a photographer I wouldn't be spending this kind of money for a 6-pound 70-200mm zoom because it's sharper at the wide end. And even shooting 6k video I suspect you'd be hard pressed to detect a huge difference in your footage at 70mm. But now you can have a true cinema lens with long focus and zoom throws, properly geared for follow (and zoom) focus, parfocal and without significant breathing that's as sharp as any photo lens made.

While $20,000 is sticker shock for my photography colleagues, consider a set of three Cooke Panchro primes covering the same focal length at the same aperture costs $22,000 and doesn't even approach the Zeiss in resolution. Plus Zeiss lenses don't tend to spit out focus helicoid collars and require a $600 repair every 3 months like Panchros do.

 

Roger Cicala and Aaron Closz

Lensrentals.com

April, 2012

 

BTW - I know what you're thinking. Yes, I do love my job.

26 Responses to “First Look: Zeiss CZ.2 70-200mm T2.9”

Lee Saxon said:

Can you add the Nikon Imatest numbers, just for curiosities sake?

salim said:

Were the lenses mounted on the tripod or the camera body was mounted on the tripod. At such a heavy weight by zeiss there is going to be a small amount of rear element to sensor variation cause by gravity pulling the lens down causing lower performance in the corners (assuming you used center focusing)

LensRentals Employee

Roger Cicala said:

Salim, lens mounted to tripod for certain. It's far to heavy to put the weight on the camera mount.

LensRentals Employee

Roger Cicala said:

Lee, it's always real iffy comparing on different cameras because Imatest is comparing the camera/lens combination. But the Nikon is 875 center, 730 average at 70mm, 890 / 740 at 200mm on a D3x. All things being equal (which they aren't) the D3x should give about a 7% boost in numbers compared to the 5DII.

Roger

htf said:

Isn't your parfocal check a bit strange?

You are focusing at 70 mm, where the DOF is much larger than at 200 mm and you are surprised that one of the lenses shows an unsharp image at the 200 mm setting?

Focus at 200 mm and zoom to 70 mm ...

regards

Helmut

rastislav stanik said:

"I won’t repeat the Canon lens, it breathes significantly and the focal length changes as you zoom close."
as you focus close?
thanks for the research

CarVac said:

I find it appalling that a fully manual lens, especially of cinema-type costs, would ever be made so poorly that it would mechanically fail "every 3 months".

jseliger said:

But we thought we’d see if the Zeiss could hold it’s own against

The "it's" should be "its."

LensRentals Employee

Roger Cicala said:

Helmut, we did it both ways, of course. Results were the same.

Chris said:

Hi Roger
I wish photo lens makers had to use T stops instead of F stops too.
It would be much clearer.
Great article. Thanks. Chris

CarVac said:

Chris:

The reason we use f-stops is because people "care about depth of field", and that's what matters for DOF.

F.M. said:

Maybe is just me but, apart from video, I think a lens with no focus breathing would be an interesting approach to do focus stacking. Just dreaming, but if canon or nikon come with some kind of AF bracketing and some lenses like that, it would be very very useful.

Elmer said:

It's funny that the Zeiss lens has a text "Compact Lens 70-200" written on it when it is not compact at all.

(Haven't seen many pictures of cinema lens zoom though so this may really be compact).

Ben said:

In comparison you bet it is.

Markus said:

Roger,
do you know if the CZ zoom was a complete new development or is it based on some existing photo lens like the CZ compact primes? Maybe some Sony or Contax stuff?
I'm just wondering why they would exactly choose the 70-200/f2.8 specification and EF mount (instead of PL) and a FF image circle. Just screams 'photo' at me (and you - I've got this impression)

Thanks, Markus

Darren Evans said:

What is the diameter of this lens? we have one but it is not engraved. We need an adapting ring for a matte box.
Anyone know the diameter of this lens or where to look it up?

LensRentals Employee

Roger Cicala said:

Markus, I don't know whence the design. It may be they'll release a less expensive 'photo' version in the future, but the parfocal and lack of breathing makes me think it was designed cinema from the ground up. I would assume the found a lot of cinematographers were using 70-200s on 5Ds or full frame Canon video cameras.

Then again, being Zeiss, they might have just been showing off :-)

LensRentals Employee

Roger Cicala said:

Darren, all I have is the 95mm front element diameter.

Michael Turano said:

"It’s also really parfocal, meaning if you focus on something at 70mm and zoom out to 200mm the object is still in focus. None of the photo lenses are (although budget minded cinematographers desperately want them to be)."

I thought an earlier LenRentals article listed the non IS version of the Canon 70-200 as being parfocal. Has your opinion about that changed?

LensRentals Employee

Roger Cicala said:

Michael, the older version was fairly parfocal but the new one is not.
But what is parfocal is changing because sensors are larger. Back when we wrote that 2/3" sensors were considered top of the line, or nearly so, and they have a much greater depth of field than today's full-frame and APS-C size video sensors, which have shallower depth of field. The older lenses that were 'nearly parfocal' aren't always up to snuff with larger sensors.

Roger

RVB said:

This baby was designed from the ground up as a cine lens.. And in the world of cine lenses its not that big or heavy..

Arnold George Dorsey said:

OK, I admit it: you, Roger, and your son are my heroes. You both spent hundreds of thousands of dollars at the best universities, dedicated hours and hours studying in libraries or laboratories and made countless personal sacrifices so that you graduate as a physician and attorney, respectively. Yet, after all that, you both realize that your real calling--and bigger benefit to mankind--would be to start Lens Rentals. What Medicine and the Law lost we have gained. Another insightful review Roger. I love your fact-filled articles. Its not everyday I get to read a piece where the author uses concepts like "standard deviation". When we will see your review of Nikon's 800mm "Veyron"?

One last question: why didn't you just skip the whole university-med-school--boards--private practice thing and just go straight to being one of Photography's best gear-head?

JR said:

Hi Roger,

Can you please help me understand something?

In your "Revisit" of the Nikkor 24-120mm F4 you said: "The center, which was already quite excellent, doesn’t really improve with stopping down much except a bit at the long end. The corners do sharpen up nicely at f/5.6 and from a pure MTF 50 standpoint I’d call them acceptable at this aperture."
http://www.lensrentals.com/blog/2013/03/nikon-24-120-f4-vr-revisited

What is "acceptable" to you?

I see that in this post you have the Canon, "the best 70-200 f2.8 photo you have", with corner numbers in the order of 575 & 525. Are those also "acceptable"?

Did you test with the Nikkor 24-120mm F4 stopped down to F8?
I'm curious to see if the corners would be "acceptable" at that aperture.

Regards,
JR

LensRentals Employee

Roger Cicala said:

JR,

Remember I'm looking at things from the point of view of maximizing the camera's ability and Imatest (and DxO) are testing systems of cameras and lenses. That's why comparing a test on one camera like a D800 to another, like the 5DIII is always a soft comparison. Not only sensor size and resolution are being tested, but also microlens structure over the sensor, etc.

Corners of 450 on a 5D Mk II are quite good, while on a D800 I'd call them acceptable. Especially when comparing apertures that are different. As an example, the Sigma 35mm f/1.4 can get corners of 440 lp/ih at f/1.4 and 550 at f2.0 on a 5DII which is outstanding. The Canon zoom gets the numbers you mention at f/2.8 and f/4, again outstanding (given a zoom).

I expect D800 to resolve at least 15% higher on the same lens, so corners of 625 lp/ih get into my outstanding range there.

All that being said, the 24-120 is a really excellent lens, especially given it's 5X range. But what is excellent performance for a 5X zoom is not the same absolute performance you'd get from a prime.

Roger

JR said:

"I expect D800 to resolve at least 15% higher on the same lens, so corners of 625 lp/ih get into my outstanding range there."

Thanks, Roger! That's EXACTLY what I wanted to know; namely, what your criteria was for "outstanding" on the D800.

I currently own the Nikkor 24-120mm F4 and use it with a D600 as my go anywhere, mid-range zoom. I'm very happy with it and surprised by how well it performs on this sensor; and stopping down surely helps for landscape work, since corner softness is an issue at some focal lenghts. It doesn't have the center or corner performance of my 70-200mm f2.8, but that's to be expected!

I'm looking to switch to the 24-70mm f2.8. I've owned a comparable Canon lens(28-70mm f2.8) so I know how heavy and unruly it can be for travel and backpacking photography; which is how I'd use the 24-70mm f2.8 the most.

I'm hesitant about making the switch(can't afford to keep both) and was hoping you could tell me the the actual, or approximate, corner numbers for the 24-70mm f2.8 on the D600 or the D800. Does it resolve that "15% higher", as you'd expect from a pro-grade lens?

Basically, what am I gaining, if anything, by making the switch?

Your feedback is much appreciated,
JR

JR said:

Correction to my previous post. I meant to write "It doesn’t have the center or corner performance of my 80-200mm f2.8"! I don't own a 70-200mm.

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