Zeiss 18mm Distagon Review
A first look at the Zeiss Distagon T* 3.5/18 ZE. Along with tests vs the TSE 17mm and the 17-40 F/4 L
*(Updated 1/11/10 – added vignetting & distortion test)*
In a quest for the best possible optical quality in an ultra-wide-angle lens to accompany the high megapixels of today’s Canon DSLRs, I immediately became interested when Zeiss announced that it was finally going to release it’s legendary lens series in EOS mount. This announcement came well over a year ago and a lot Canon photographers (myself included) have been waiting patiently.
As I have written before, the 17-40 L is a great lens and a great value, but the softness in the corners and edges is so apparent, especially with higher-megapixel bodies, that if one wishes to make large prints (the kind these bodies were designed for) they will be disappointed in the corner-to-corner sharpness… This is what brought me to the TS-E 17mm and although that lens has proven to be quite possibly the answer in optical quality, it has a few inherent downfalls – most notably the lack of ability to use any front or rear filters. This brings us to the Zeiss line.
Zeiss has been making high-quality manual focus lenses for quite some time, and Nikon users have been able to benefit from this, as Ziess has manufactured Nikon-mount glass for a while now… Nikon and Pentax users may be familiar with it, but Canon users often aren’t. People with Canon bodies have had to use a third party adapter, often with inconsistent results. Now with a full line of legendary Zeiss lenses in EOS mount, a lot of photographers who don’t need autofocus are going to be very happy.
Build and construction
Without a doubt, this lens has the best physical quality of any wide angle lens I have ever used. The precision of the focus ring along with the weight and balance when mounted is second to none. Nothing Nikon, Canon or Sigma makes in this focal range is in the same league. If you are particular about your gear and the way it handles, you won’t be disappointed here. This is a precision instrument.
One of the first things you’ll notice upon opening the box is the Zeiss hand-signed and checked inspection list. I don’t consider myself as much of a gear fiend as many other photographers out there, but I’ll admit, I was very impressed at this lens fresh out of the box… As pictured above, the 18mm comes with a well made lens hood that locks firmly into place. Also included is a center-pinch front lens cap that makes removing and installing pretty easy with the hood attached.
The front thread for filters is 82mm, which can be a little more expensive and harder to find than the norm, which is 77mm. But the 82mm filter size serves an important purpose: it controls vignetting when front filters are used. Notice the picture below and you’ll see how the barrel dramatically widens at the front.
Short and compact, it weighs in at 470 grams (16.5 oz), which is about the same as the 17-40 L and much less than the TS-E 17mm which weighs 820 grams (28.9 oz).
This is why we all came… How does it perform optically against some other major players in the UWA range for Canon?
Zeiss 18mm vs 17-40 L vs 17mm TS-E
Above is the test shot where the 100% crops below came from. All photos were taken with a 1Ds Mk III which is Canon’s highest megapixel camera body to date (tied with the 5D2) and really exposes the weaknesses of a lens’s optics, which helps for this test. All shots were tripod mounted, with mirror lock-up enabled and cable release used. They were all taken at ISO 100 and each shot at the same shutter speed per aperture down the line. No sharpening or post processing was applied. The 17mm TS-E was (obviously) shot with no tilt or shift applied.
You will notice at the extreme corners, the difference in focal length. The 17-40 has enough distortion at 17mm to make it slightly wider than the 17mm TS-E, which is in turn just slightly wider than the Zeiss 18mm.
Note that the 100% test crops below may be slightly resized for the blog page. In this case, click the photo for the full size if you wish…
As you can see- in the center frame the playing field is very even, and although diffraction at F22 hinders all of the lenses, one could easily draw the conclusion that the 17-40 L is just as good as the other two much more expensive lenses in the center… But the other areas are a different story as you’ll see…
The main factor that becomes apparent with the above shots is the 17mm TS-E‘s ability to not only retain better detail than the other lenses, but completely control (if not eliminate) chromatic aberrations. The red/purple fringe is nowhere to be seen on the TSE crops, and seems worst with the Zeiss than even the 17-40, although that may simply be due to the softness of the 17-40…
Both Canon lenses slightly out-perform the Zeiss in sharpness on this side of the frame… Trust me when I say that human error in focus is not the factor here, as I thoroughly checked the center point focus with live-view on all three lenses, even after in camera focus confirmation. One must also remember that with lenses there is always copy variation, and when dealing with floating glass elements like in the Zeiss, a tiny fraction of difference can cause some slight softness…
Extreme left corner
(click on each photo group for full size)
This is where the Zeiss performs the best, and as you can see, it’s also where the 17-40 is at it’s worst… Both Canon lenses clean themselves up with smaller apertures, but the Distagon still wins the corner sharpness test. I’m not sure if it’s noticeable on these smaller crops, but I did once again notice a large amount of CA from both the Zeiss and the 17-40 on the edges of some of the mulch here. The TS-E had no CA to speak of.
Extreme right corner
Once again the Zeiss performs the best. Too bad it can’t keep the sharpness across the entire frame…
Another set of 100% Crops (from a different scene)
These are right side of the frame crops from the flare test shots below. All lenses were focused to infinity.
The following shots are unsharpened full frames shot toward the sun at f8. In fairness to the TS-E, I did not use the lens hoods on either the Zeiss or 17-40.
You will have to click on each thumbnail photo to see the full size image and do some zooming-in to see the flare spots (they are there) throughout each photo due to the dark scene. The conclusion is that even with it’s bulging front element, the 17mm TS-E controls flare slightly better than the Zeiss, which is in turn, far better at flare control than the 17-40 L.
Vignetting / Distortion
All three photos shot tripod mounted with the same exact exposure at F/4
Shots were leveled with both a hot-shoe bubble leveler and tripod base-leveler. I take no responsibility for the masonry.
(click on each photo to view full size)
It’s obvious the TS-E once again out-performs both of the other lenses in vignetting as well as barrel distortion, with the Zeiss in second place for distortion and third place for vignetting, depending on how you interpret the light fall-off… I’ll let you draw your own conclusions from the images…
Below are some more 100% crops. These are from the bottom left of the frame in the above test.
I’ll be the first to admit I’m a just slightly disappointed in the Zeiss 18mm Distagon. Not doubt it’s a great lens and a finely crafted piece of optical equipment, but I was hoping it could possibly replace my Canon 17mm TS-E for normal prime UWA use. It will, however most likely replace my 17-40 L as the lens I’ll use when I need something that can take a front filter mounted on it. (I rarely use the 17-40 at anything other than 17mm)
In almost all of the tests, it scores right in the middle, between the two Canons respectively. Coming in second to a $2,500 lens is nothing to be ashamed of.
If you are considering buying this lens, I’d weigh the options first… Remember that Zeiss does not make an autofocus lens, so you’re stuck with manual, which shouldn’t be that big of a deal for most people since lenses in this focal length are not usually used for subjects that require quick autofocus and when dialing in an exact focal length, one usually does this manually anyway. The 82mm filter thread can prove frustrating at times due to the fact that many manufacturers charge much more for this size and retailers are often out of stock as well. The Zeiss won’t blow you away in optical ability, but it is still a decent step up from both the 17-40 L and 16-35 L, in my opinion.
If you find yourself dealing with subjects that produce a lot of chromatic aberration, you won’t find the Distagon to solve your problems there. It is a great performer in corner to corner sharpness and flare, but not in CA control.
All in all, it’s a great lens and definitely lives up to the Zeiss reputation, but one should weigh the options before deciding. If you are posting mostly on the web and rarely print your photos past 10×15, the 17-40 is a much better value and will save you some money… But for my uses, it’s definitely worth keeping and although it can’t replace my 17mm TS-E as my main ultra-wide-angle prime, it does cost just over half of what the TS-E costs, weighs just over half as much, handles better and can hold it’s own in the sharpness department.
Thanks for reading