When I received the Zeiss Milvus 21mm f/2.8 Lens, my first declaration was that it was the world's most beautiful lens. The Zeiss 18mm f/2.8 Milvus Lens is a lightly smaller version of that lens and, with a slightly higher cuteness factor, may take that title from its sibling. With a repeat performance, the Milvus 18 feels at least as good in your hands as it visually appears and mechanically functions perhaps even better. The always important image quality factor has not been left out here.
Zeiss has unleashed a complete lineup of Milvus lenses in the last year and a half and, while all of these lenses share many significant upgrades over the Classic line, not all incorporate a new optical design. A fact made obvious by the incorporation of a wider aperture than found in its Zeiss 18mm f/3.5 Classic Lens predecessor is that the Zeiss 18mm f/2.8 Milvus Lens indeed has received a new optical design (unlike the just-referenced Zeiss 21mm f/2.8 Milvus lens). This Milvus refresh brings a nicely improved lens, from both an aesthetic perspective and from a durability one (including weather sealing), and few will be disappointed by the image quality delivered by this lens.
Before reading any further, you need to know that this lens, like all other Zeiss Milvus lenses, is manual focus only. If AF is on your requirements list, this lens will not satisfy you. If you think a manual focus only lens might work for your applications, this lens is worthy of consideration.
Make focal length selection a priority when choosing a lens because focal length matters. While focal length determines working distance and therefore perspective, very wide angle focal lengths are a lot about making foreground subjects large in relation to the background subjects and about including a lot of background in the frame. The 18mm angle of view is notably able to give the viewer a sense of presence in the images captured by it.
I consider 18mm to be a "scapes" focal length. It is useful for most photography terms that "scapes" can be naturally appended to, including landscapes, nightscapes, cityscapes, buildingscapes, roomscapes, etc. Landscape photographers should have the 18mm (or at least close to 18mm) focal length covered in their kit. The 18mm angle of view will take in a large portion of the night sky or show the big picture of a city. Architects will appreciate this angle of view and real estate photographers will find uses for this lens inside and out.
Include peoplescapes in the list, with environmental photos of individuals and groups captured at a wide range of locations from scenic landscapes to birthday parties in small rooms being a 18mm capability. However, care must be taken when photographing people at wide angles. For example, if multiple people are in the 18mm frame and their distance from the camera varies significantly, those in front will appear larger than those in the back. Also, too-close human subjects may result in unpleasing perspectives.
Talking about people, weddings are all about people and helping to cover these and similar events is a big strength of this lens. Capture a bride getting ready with her attendants surrounding her. Capture the first dance at the wedding reception, with this lens capturing the bride and groom large in the frame with the guests encircling them in the background. Of course, capturing moving subjects with a manual focus lens can be challenging, but using Live View (especially magnified on the area of optimal subject framing) can increase one's in-focus success rate.
Videographers can find many uses for 18mm.
I like to look at focal lengths in comparison format and, since this lens has only one focal length, I'll borrow a comparison from the Sigma 12-24mm f/4 DG HSM Art Lens review that also covers 18mm.
On an ASP-C sensor format body, the 18mm focal length provides a narrower angle of view than on a full frame body, similar to approximately a 28.8mm lens mounted on a full frame model. As hinted to by many lens manufacturers having 28mm prime lenses in their lineup (including one of the two current Zeiss Otus lenses), this focal length is also quite useful. Falling between two extremely popular focal lengths, 24mm and 35mm, the 28mm-equivalent angle of view also falls into the middle of the uses covered by these focal lengths. While there is overlap in the list of uses for 18mm on full frame vs. on APS-C, the overall lists are somewhat different with 28.8mm having more general purpose appeal. This angle of view is useful for photojournalism and other similar uses with a more-natural perspective being typically obtained.
While an f/2.8 max aperture is 2/3 of a stop faster than the previous Zeiss 18mm lens and while f/2.8 is often considered fast, f/2.8 is not especially fast for a prime lens. Still, at least until the announced Sigma 14mm f/1.8 DG HSM Art Lens arrives, the Zeiss 18mm f/2.8 Milvus Lens has the widest aperture available in a major brand full frame prime lens wider than 20mm. But, that is not saying a lot as there are many f/2.8 full frame zoom lenses covering this focal length.
A wider aperture invariably means heavier weight, larger size and higher price. So, the f/2.8 aperture happens to be where Zeiss targeted this overall package. And again, f/2.8 is rather fast and useful for stopping action and camera motion in relatively low light levels. This aperture is wide enough to create a bright viewfinder and wide enough to show some background separation using shallow depth of field.
Here is an example of the maximum background blur this lens can produce:
For this image, the lens was set to its minimum focus distance with a somewhat distant background.
This lens has an f/2.8 aperture and you will not be afraid to use it. Images captured at f/2.8 (assuming proper photographic technique) are sharp across the frame.
As illustrated by our demanding test chart, the center of the frame details show a nice contrast increase gained by stopping down from f/2.8 to f/4 where the results become razor sharp. You may have trouble seeing this improvement in real world results such as in this comparison:
The above images were captured with an EOS 5Ds R in RAW format and processed in DPP using the Standard Picture Style with sharpness set to "1". The center of the frame was then cropped to 100% resolution. Within the center of the plane of sharp focus, differences are challenging to see in this comparison.
Full frame corners have very good resolution at f/2.8 and, especially with contrast increasing as vignetting clears at narrower apertures, corners are looking excellent by f/5.6. Landscape photographers are among those who value sharp corners and ... this lens will impress in this regard.
The first three crops shown below are from the extreme top left corner of the frame and the second set are from the bottom right.
All four corners were similar in sharpness, indicating that the lens is properly aligned and results captured at close distances were similar to those captured at long distances.
I mentioned vignetting and all full frame lenses show this at their widest apertures when mounted on full frame cameras. The question to ask is "How much vignetting is there?" There is a noticeable amount at f/2.8 – between 3.5 and 4 stops. The shading clears quickly at narrower apertures with just over 2 stops remaining at f/4 and just over 1 stop at f/5.6. While that amount is just-noticeable in some images, stopping down does not remove the last stop of shading.
Though few will consider 3.5-4 stops of vignetting to be less than strong, these numbers are noticeably improved over the predecessor lens – by approximately 1 stop.
Vignetting can be corrected during post processing with increased noise in the brightened areas being the penalty. Vignetting can also be simply embraced, using the effect to draw the viewer's eye to the center of the frame.
The most frequently noticed type of CA (Chromatic Aberration), lateral (or transverse) CA, shows as different colors of the spectrum being magnified differently with the mid and especially the periphery of the image circle showing color fringing along lines of strong contrast running tangential (meridional, right angles to radii) as this is where the greatest difference in the magnification of wavelengths exists. I'll call it "LatCA" and in a prime lens, latCA is usually very well controlled.
There should only be black and white colors in this top left corner of the frame 100% crop, so in this case, the amount of LatCA showing in the corners is noticeable. Fortunately, lateral CA is easily software corrected by radially shifting the colors to coincide with little penalty paid in terms of image details.
A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light, or more simply, different colors of light are focused to different depths. Spherical aberration along with spherochromatism, or a change in the amount of spherical aberration with respect to color (looks quite similar to axial chromatic aberration, but is hazier) are other common lens aberrations to look for. Axial CA remains at least somewhat persistent when stopping down with the color misalignment effect increasing with defocusing while the spherical aberration color halo shows little size change as the lens is defocused and stopping down one to two stops generally removes this aberration.
In the real world, lens defects do not exist in isolation with spherical aberration and spherochromatism generally found, at least to some degree, along with axial CA. These combine to create a less sharp, hazy-appearing image quality at the widest apertures.
Shown below are a pair of 100% crops from a single EOS 5Ds R-captured image. The just-described aberrations would readily show in this image with different colors surrounding the foreground and background blurred highlights.
While perhaps not 100% perfect, this lens is looking very good in this regard. The silver stays, essentially, silver from in front of the plane of sharp focus through behind it.
The Zeiss Milvus 18mm f/2.8 Lens is very impressive in its ability to avoid flaring and is much-improved over the 18mm Classic. The effects of flare can be very destructive to image quality and it is sometimes extremely difficult to remove these effects during post processing. Even with the sun in the corner of the frame and the aperture narrowed to f/16, very few flaring effects can be seen and few lenses perform better in this regard.
Lenses vary in their ability to render details precisely and the difference becomes especially noticeable in the image periphery. The tiny point light sources that stars in the night sky provide are a good subject to use for this differentiation. One of the lens defects commonly made apparent by peripherally-placed stars is coma. Coma is generally recognized by sharp contrast towards the center of an image and long, soft contrast transition toward the image periphery. Coma is most visible in wide aperture corners and significantly resolves when the lens is stopped down.
The above image is a near-top-left corner crop from an image captured with the EOS 5Ds R. This position in the frame was directed toward the north star to help avoid star trails. Stars do not have wings and they should be slightly rounder in shape, but relatively speaking, this lens is not performing badly here.
Low or no linear distortion is an advantage typically held by a prime lens, though this lens does show some slight barrel distortion. The older Zeiss 18 had some mustache/wave distortion, so most will see this change as positive. The image below shows the entire top-of-the-frame width and the horizontal lines are close to, but not quite, parallel.
While an 18mm f/2.8 lens is not going to produce the world's strongest background blur, the quality of the blur that this lens creates, referred to as bokeh, is nice. Here are two examples of out-of-focus background specular highlights.
These highlights stay nicely rounded at narrower apertures and the centers are reasonably smoothly filled.
This lens' 9 aperture blades, when stopped down, turn point light sources into 18-point stars. Here is an example using a point light source we all share in common:
Optically perfect lenses do not exist, but this one ranks quite high on the list. Many would agree that the strong vignetting is this lens' weakest point and in that regard, it compares relatively well to other options.
Image quality is highly dependent on accurate focusing and, with all manual focus lenses, including the Zeiss Milvus line, that accuracy is completely in your hands. Fortunately, Zeiss Milvus lenses deliver the ultimate manual focusing experience.
The extremely smooth focusing ring has a huge 144° of rotation with very precise manual focusing available at all focus distances.
The focus ring diameter is flush with the lens barrel with a modest size, consuming the rubber-coated portion of the lens and the extremely well-marked (etched) focus distance values behind it. It is not difficult to find the focus ring as it is located just behind the tapering section of the lens, though gloves increase this challenge. The focus ring resistance is ideal and there is no play. As I've been saying, there are few non-Zeiss lenses as nice to manually focus as the Milvus lenses.
As with all Milvus lenses, infinity and minimum focus distances are hard stops. That feature means that focus distance settings/marks are easily repeatable, an attribute highly valued by videographers. Distant subjects (such as stars) are typically sharp before the hard stop at the infinity end due to adjustment provided for the actual infinity focus position to potentially change with temperature.
The Zeiss Milvus 18mm f/2.8 provides a full DOF (Depth of Field) scale including etched aperture marks covering the entire aperture range, from f/2.8 through f/22. While some other other-brand lenses include depth of field markings, few lenses provide markings wider than f/11.
Subjects change size slightly as this lens is focus racked. While this attribute is not unusual, photographers intending to use focus stacking techniques involving focus distance adjustment, videographers pulling focus and anyone very-critically framing a scene will care about this attribute.
As mentioned, focus accuracy is 100% your responsibility with a manual focus-only lens. In the old days, manual focusing was all we had. However, in those days, we were given bright viewfinders with split image rangefinders and microprisms.
Today's DSLR viewfinders are optimized for autofocusing and the provided focusing screen makes precise manual focusing a challenge. Focusing screens can be replaced (either via accessory drop-in replacements or via a service provided by a third party camera service center), but one challenge potentially remains and that is focus calibration. If the focusing screen is not precisely calibrated with the imaging sensor, perfect viewfinder-based focusing can result in a front or back focus condition.
The viewfinder's in-focus indicator light will come on when the camera thinks that accurate focus has been acquired, but this is an imprecise indication. Ideal is to use live view (on the back of the camera or in an electronic viewfinder) under maximum magnification where very precise manual focusing can be very reliably established. The downside of course is that not all situations permit use of the magnified live view method. Though depth of field is related in part to the reproduction ratio being used at the time (with distance to the subject and focal length being factors), I often use wide angle lenses such as this one to take in the bigger picture and in those cases, I have a greater manual focus success rate using the stock focusing screen.
A 9.8" (250mm) MFD (Minimum Focus Distance) from an 18mm wide angle lens is not going to impress you with the resulting MM (Maximum Magnification) spec. Still, the 0.14x figure is a significant improvement over the Zeiss 18mm f/3.5 Classic's 0.09x MFD.
|Canon EF 16-35mm f/2.8L III USM Lens||11.0"||(280mm)||0.25x|
|Canon TS-E 17mm f/4L Tilt-Shift Lens||9.8"||(250mm)||0.14x|
|Canon EF 20mm f/2.8 USM Lens||9.8"||(250mm)||0.14x|
|Nikon 14-24mm f/2.8G AF-S Lens||11.0"||(280mm)||0.15x|
|Nikon 19mm f/4E PC Lens||9.8"||(250mm)||0.18x|
|Nikon 20mm f/1.8G AF-S Lens||7.9"||(201mm)||0.23x|
|Sigma 20mm f/1.4 DG HSM Art Lens||10.9"||(277mm)||0.14x|
|Tamron 15-30mm f/2.8 Di VC USD Lens||11.0"||(280mm)||0.20x|
|Zeiss 15mm f/2.8 Milvus Lens||9.8"||(250mm)||0.11x|
|Zeiss 15mm f/2.8 Classic Lens||9.8"||(250mm)||0.11x|
|Zeiss 18mm f/2.8 Milvus Lens||9.8"||(250mm)||0.14x|
|Zeiss 18mm f/3.5 Classic Lens||11.8"||(300mm)||0.09x|
|Zeiss 21mm f/2.8 Milvus Lens||8.7"||(220mm)||0.20x|
Here is a MFD and MM example:
I'm guessing that this picture does not say "indoors in the middle of winter in Pennsylvania" to you, but ... sometimes one needs to be creative to fill a need. I simply spread sand on (and around) a large piece of paper in direct sunlight, smoothed the sand, scattered loose sand on top (to get the grain), placed the sand dollar, set the lens to its MFD, adjusted the framing distance until in focus and captured the photo. Fortunately, I had all of the "around" sand vacuumed up before my wife came home.
What the image demonstrates is that this lens' maximum magnification would allow many of the 2.8" (71mm) sand dollars to fit side-by-side into the frame. So, while this lens can still show a wide perspective and can create a sense of presence for the viewer, it will not be confused with a macro lens.
Magnification from wide angle through standard/normal focal length lenses is generally significantly increased with the use of extension tubes. These are basically as their name implies, hollow tubes (typically with electronic connections) that shift a lens farther from the camera. Doing so allows the lens to focus at closer distances (at the expense of long distance focusing). However, at this wide angle, even a relatively short 12mm extension tube reduces the focus distance to shorter than the lens hood. While you might be able to photograph something with this lens in front of a 12mm ET, you are going to have a hard time lighting the extremely close subject and the corners are going to be blurred.
If you spend a lot of time with a camera in your hands, I'm sure that you appreciate using a quality lens. All of the Zeiss Milvus lenses feel like precision instruments and nearly assured is that simply using these lenses will be a fun time. All photographers can appreciate the aesthetically pleasing curved lines they incorporate.
Here is a look at the two Zeiss 18mm lenses with the Classic lens appearing on the left and Milvus on the right.
There were some substantial design changes made to the Milvus lens and the similarities are few.
We first saw the fundamentals for the new Milvus design with the introduction of the Zeiss Otus line. The Milvus lens series has inherited the smooth overall flow and the smooth rubber focus ring is similarly Otus-like. All lettering and other markings on this lens are etched into the metal lens barrel, focusing ring and lens hood. Having the focal length and aperture easily visible on the hood is especially nice, making lens ID easier (especially if one also owns the Milvus 15 and Milvus 21).
This is a fixed-size, rear-focusing lens. Focusing causes the rear element to shift in and out slightly, but externally, this lens does not change size with focusing.
With autofocus, image stabilization, a zoom range and any other similar features omitted, this lens needs no switches and that leaves nothing but focus ring and lens barrel. Just enough fixed lens barrel is available behind the focus ring to grasp for mounting and dismounting.
Merge a very high quality build with few features and high reliability can be the expected result. Featuring an all-metal exterior, the Milvus lenses all feel like they would last a very, very long time even with regular professional (ab)use.
A new feature for this lens and the entire Milvus line is dust and moisture sealing. While most of this lens is black with high-visibility white markings, a touch of Zeiss blue found in the lens mount gasket gives this lens an even classier appearance.
The Zeiss Milvus 18 is a medium-small lens that is sized nicely for use and weighted lightly enough for even long term use. But, a strong build quality will often show up on the scales and as might be expected, this lens is relatively heavy for a prime lens with these specs. The table below shows manufacturer specs and that Zeiss includes the 1.6 oz (45g) lens hood in the weight spec should be taken into consideration.
|Model||Weight||Dimensions w/o Hood||Filter||Year|
|Canon EF 16-35mm f/2.8L III USM Lens||27.9 oz||(790g)||3.5 x 5"||(88.5 x 127.5mm)||82mm||2016|
|Canon EF 20mm f/2.8 USM Lens||14.3 oz||(405g)||3.1 x 2.8"||(78 x 71mm)||72mm||1992|
|Nikon 14-24mm f/2.8G AF-S Lens||34.2 oz||(969g)||3.9 x 5.2"||(98 x 131.5mm)||mm||2007|
|Nikon 19mm f/4E PC Lens||31.2 oz||(885g)||3.5 x 4.9"||(89 x 124mm)||mm||2016|
|Nikon 20mm f/1.8G AF-S Lens||12.6 oz||(357g)||3.2 x 3.1"||(81.3 x 78.7mm)||77mm||2014|
|Sigma 20mm f/1.4 DG HSM Art Lens||33.5 oz||(950g)||3.6 x 5.1"||(90.7 x 129.8mm)||mm||2015|
|Tamron 15-30mm f/2.8 Di VC USD Lens||38.8 oz||(1100g)||3.9 x 5.7"||(98.4 x 145mm)||mm||2014|
|Zeiss 15mm f/2.8 Milvus Lens||33.4 oz||(947g)||4 x 3.9"||(102.3 x 100.2mm)||95mm||2016|
|Zeiss 18mm f/2.8 Milvus Lens||25.5 oz||(721g)||3.5 x 3.7"||(90 x 93mm)||77mm||2016|
|Zeiss 18mm f/3.5 Classic Lens||16.6 oz||(470g)||3.4 x 3.3"||(87 x 84mm)||82mm||2010|
|Zeiss 21mm f/2.8 Milvus Lens||30 oz||(851g)||3.8 x 3.7"||(95.5 x 95mm)||82mm||2015|
For many more comparisons, review the complete Zeiss 18mm f/2.8 Milvus Lens Specifications using the site's Lens Spec tool.
Since there is a rather wide range of lens options to compare, I'll split the visual comparison between the primes and zooms with the primes obviously coming first:
Positioned above from left to right are the following lenses:
The same lenses are shown below with their hoods in place.
And now, comparing the Zeiss to a set of f/2.8 zooms covering the 18mm focal length:
Positioned above from left to right are the following lenses:
And, as before, below are the same lenses with affixed hoods.
Use the site's product image comparison tool to visually compare the Zeiss 18mm f/2.8 Milvus Lens to other lenses.
This lens accepts standard 77mm front filters, smaller than the 82mm size utilized by the Classic lens. While 82mm filters are increasingly common, 77mm filters are even more common and being smaller means a modestly lower price. Note that using a standard thickness circular polarizer filter will increase light falloff in frame corners by nearly .5 stops. A slim model such as the B+W XS-Pro is highly recommended for this lens.
All of the Zeiss Milvus lenses come with a very strong metal hood included in the box. These hoods are designed to beautifully integrate with the lens body, providing a substantially enlarged and very comfortable working surface. This sculpted hood is so well integrated that the lens doesn't look quite right without the hood in place.
The 18's hood is large enough to provide significant protection from bright light and impact while circular polarizer filters remain accessible for adjustment even with the hood in place. I am happy to report that, unlike the predecessor lens, the Milvus 18's hood cannot be installed in a position that causes strong mechanical vignetting. Reversed, Milvus hoods stow compactly. These hoods feature interior flocking for maximum light blocking.
Milvus line lenses come with an upgraded lens cap. While a lens cap may not seem important, it is a part of the lens that most of us use a lot and the cap staying properly attached is important for protection of the lens. The Zeiss Milvus front lens cap is one of the nicest I've used, featuring an easily grippable center-and-side-pinch design.
The rear cap features a double-wall design, a change from the older single-wall cap included with the pre-Milvus lenses. Zeiss says that the purpose for the rear cap redesign is purely aesthetic, though it appears to be a slightly more protective design.
Zeiss does not miss with the out-of-the-box experience. Remove the outer box sleeve to find a somewhat large but very protective hinged box with cut-out foam cradling the lens and hood in place. This box is nice enough that I wish Zeiss had taken the next step of providing a hard plastic shell case with latches or something similar that would hold up better for use in the field. At review time, the Lowepro Lens Cases get my vote for very nice and affordable solutions for single lens storage, transport and carry.
"I bought the Milvus 18mm f/2.8 Lens because of its low price!" is a statement that you will here no one make. There is a price to be paid for superior quality and the price of this lens will be a hurdle for some. The peace of mind that comes from having a reliable lens has value and a lens that doesn't fail during a big shoot has far more value.
The Zeiss Milvus 18mm f/2.8 Lens is available in Canon (reviewed) and Nikon mounts. At this point in the review, I always include my standard disclaimer, warning of potential issues when using non-camera manufacturer brand lenses. Since the Zeiss Milvus lenses do not include autofocus, I view the risk of incompatibility in existing or future camera introductions as being quite low. Zeiss Milvus lenses include a 2 year warranty, twice as long as Canon's USA and international warranties, but less than half as long as Nikon USA's 5-year lens warranties.
The Zeiss Milvus 18mm f/2.8 review lens was retail sourced.
The wider the focal length, the greater the difference 1mm makes in the image. That said, there is only one other 18mm prime lens in our database and that is the Zeiss 18mm f/3.5 Classic Lens. So, it seems logical to make that the first lens to compare the Zeiss 18mm Milvus to.
The Milvus lens has a wider aperture, shows less vignetting, less flare, less distortion and less LatCA. The newer lens is larger, heavier and weather-sealed. Overall, the Milvus is a strong upgrade and I'd much rather have this option, but ... the Classic is considerably less expensive and that fact garners attention.
Add 2mm to the focal length and a trio of alternative prime lenses show on the board. Those are the Canon EF 20mm f/2.8 USM Lens, the Nikon 20mm f/1.8G AF-S Lens and the Sigma 20mm f/1.4 DG HSM Art Lens. All three of these alternatives feature autofocus to their advantage. The Canon costs about 1/4 as much, the Nikon costs under 1/2 as much and the Sigma also costs under 1/2 as much as the Milvus. The Nikon and Sigma have wider apertures.
The Zeiss is considerably sharper in (especially) the periphery of the image circle than the Canon and Nikon. At f/2.8, with the Sigma stopped down two stops, the Sigma is sharper in the center, though it has modestly more aberrations affecting corner performance. At f/4, the Sigma is sharper mid-frame but it shows more LatCA in the corners. At f/5.6, the Sigma loses the last of its advantages.
The Canon has slightly more vignetting, the Nikon has less and at f/2.8, the Sigma has much less. The Zeiss wins the flare contest and the Canon loses by the most. The Canon has less distortion, the Nikon is similar to the Zeiss and the Sigma has the most distortion.
The Canon has only 5 aperture blades (vs. 9) and is modestly shorter. The Nikon has 7 aperture blades, weighs just over half as much and has a much higher MM (0.23x vs. 0.14x). The Zeiss' focus ring has a greater rotation amount than the others and has fixed stops with easily repeatable marks. The Zeiss is weather sealed.
If I had to bet on one lens model holding up better than the others, I'd pick the Zeiss. However, the features and price of the Sigma 20mm f/1.4 are going to win a lot of comparisons.
If 18mm doesn't seem just right to you, Zeiss also has 3mm wider and 3mm longer covered in similar Milvus lenses. The Zeiss 15mm f/2.8 Milvus Lens and Zeiss 21mm f/2.8 Milvus Lens are excellent alternatives.
Far more popular than prime lenses are zoom lenses and in this case, one does not need to give up any max aperture to go with a zoom option. In addition to having a range of focal lengths available, all of the zoom lenses referenced in this review have autofocus, another highly useful feature.
The top zoom contender to the Zeiss Milvus 18 is the Canon EF 16-35mm f/2.8L III USM Lens. Priced nearly as high as the Zeiss, the Canon has f/2.8 image quality that slightly bests the Zeiss. We tested the Canon at 16mm and 20mm, so 18mm results must be interpolated, but ... the Canon proves very similar to the Zeiss in most image quality regards (a remarkable feat). The Canon is longer and weighs slightly more. The Canon's MM is significantly higher, though that advantage happens at 35mm (0.25x vs. 0.14x). The Zeiss prime is less complicated in its build and therefore most likely will prove more reliable than any zoom under rough use.
On the Nikon side of the fence is the very popular 14-24mm f/2.8G AF-S Lens. Although we don't have an apples-to-apples comparison between these two lenses, the Zeiss appears to be sharper and to have less LatCA. The Nikon shows less vignetting, more flare and slightly more distortion at 18mm. The Nikon is larger, considerably heavier, does not accept standard threaded filters, has a much shorter focus ring rotation (60° vs. 144°) and is modestly less expensive.
Another lens worth including in this comparison is the Tamron 15-30mm f/2.8 Di VC USD Lens. The Tamron brings a valuable feature not included in any of the other lenses so-far discussed here: Vibration Compensation. The Zeiss is slightly sharper. The Tamron has less vignetting, more distortion and, along with having more lens elements, it shows more flare. The Tamron is very noticeably larger, is considerably heavier, has a higher MM at 35mm (0.20x), does not accept standard threaded filters and ... is a little more than half as expensive at review time.
If you want the best image quality possible at 18mm, few lenses surpass this one. If you want the best-built 18mm lens, perhaps no lens surpasses this one. The beautifully-designed Zeiss Milvus 18mm f/2.8 Lens reliably delivers greatness and if an 18mm manual focus lens meets your needs, this lens deserves a spot on your short list.
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