The Nikon 24-70mm f/4 is one of the sharpest zoom lenses we have ever tested, which is especially impressive for what is fundamentally a kit lens. There certainly are some areas in which it falls short of perfect performance, but many of its drawbacks are relatively easy to correct in post-production (such as vignetting). We’ll cover all the most important points below.
We tested four copies of the 24-70mm f/4 to check for differences in sharpness numbers. The sample variation from copy to copy was impressively small, among the lowest deviation we have ever seen in a zoom. The overall sharpness is also quite high, regardless of focal length, even in the corners. Below are our sharpness measurements at 24mm, 35mm, 50mm, and 70mm. The next page of this review compares these numbers to the Nikon 24-70mm f/2.8 VR and 24-120mm f/4 F-mount lenses, but I’ll mention first that these are very impressive numbers, among the best we have seen so far on wide to normal range zoom lenses. Here is what the lens looks like at 24mm:
As you can see, the lens resolves a lot of detail in the center, even at f/4. Stopping down to f/5.6 helps a little, but you won’t be able to see the difference. Where it does get better as you stop down is in the mid-frame, but the edges of the frame stay about the same. Here is the lens at 35mm:
Wide open, we can see that the lens performance is pretty consistent with what we see at 24mm. However, the 24-70mm f/4 S gets noticeably better when stopped down to f/5.6 in the extreme corners.
Center and mid-frame sharpness gets even better at 50mm, although at the expense of the extreme edges due to field curvature. Stopping down the lens to f/5.6 makes things look drastically better though, so keep this in mind when shooting in the field.
As expected, sharpness levels do drop a little at 70mm, although mostly at the extreme edges of the frame. Stopping down to f/5.6 helps quite a bit, but if you want the best overall sharpness across the frame, it is desirable to stop the lens down to f/8.
As you can see, this is a very strong lens. It looks like the sweet spot of the lens is at f/5.6 for landscape and architecture photography, although when shooting at longer focal lengths, you might want to stop down between f/5.6 and f/8 to get the best results. When photographing people, you don’t need to stop the lens down at all – this is one of the sharpest zoom lenses out there in terms of its wide open performance in the center. To understand how good this lens is, you really need to look at the comparisons with other Nikon F-mount lenses.
8. In-Body Image Stabilization Compatibility
Although the 24-70mm f/4 S does not have vibration reduction lens elements, it does work with the Nikon Z camera sensor to produce better in-body image stabilization (IBIS) results than with non-native lenses.
Specifically, Z-mount lenses allow Nikon Z cameras to use all five axes of stabilization: pitch, yaw, roll, X, and Y movements (whereas adapted lenses only allow pitch, yaw, and roll). The result? Nikon claims up to five stops of image stabilization, and that proves itself to be essentially true in practice. With careful technique, you can get anywhere from 4-6 stops of improvement compared to the standard “1 / focal length” handheld rule.
And here is a 100% crop of the above image, taken with one-second shutter speed at 70mm:
This is quite an impressive performance. The images above range from two to six stops of image stabilization performance compared to the standard “1/focal length” rule.
9. Field Curvature
This lens does have some mild field curvature which can be visible under certain conditions, although is not especially objectionable. The field curvature is not particularly heavy, however, and it won’t be the primary cause of blurry photos even at its worst. You can minimize the problem by stopping down to f/5.6 or f/8 in critical cases. In short, if you’re getting blurry photos with this lens, it is much more likely to be a focusing error or a miscalculation of depth of field.
There is relatively high vignetting on the 24-70mm f/4 S, particularly at 24mm, but also at 70mm when focused at infinity. Here is a chart showing the stops of vignetting at each focal length and aperture, both close focus (CF) and infinity focus (IF):
In practice, an image with uncorrected vignetting at 24mm and f/4 – the worst levels – looks like this:
Using a slim polarizing filter is not a problem with the Nikon Z 24-70mm f/4 S – many of the images in this review were taken with a polarizer attached.
The Nikon Z 24-70mm f/4 S has high levels of distortion, although, interestingly, not all photographers who use this lens will ever notice it. In Lightroom, as well as Nikon’s own post-processing software, an automatic lens profile is applied, without any software option to remove it. This practically eliminates a photo’s distortion, making it appear as though the lens has little to no distortion at all. (You can change the image’s metadata to cheat around this in Lightroom, but few photographers will ever do so.)
However, looking at the actual RAW file in software like FastRawViewer, or even some editors like Capture One, shows that the 24-70mm f/4 S has quite a bit of distortion indeed – barrel at the wide end, and even more extreme pincushion at the telephoto:
In practice, that means RAW photos in Lightroom look a lot more corrected than they are in their original RAW format. Take a look at the below before and after comparison that shows an image that was exported from RAWDigger (before), as well as Lightroom (after):
As you can see, there is quite a bit of barrel distortion visible in the original RAW file. Lightroom automatically corrects distortion and chromatic aberration issues and you cannot easily disable that. Note that this auto distortion profile also, as a side effect, makes the extreme corners of an image look less vignetted, since you are essentially cropping out the darkest portions. My opinion is that this distortion correction is one of the reasons behind the differing opinions online about whether the 24-70mm f/4 has normal vs high levels of vignetting.
To me, the main problem is that it isn’t possible to access the non-corrected RAW file in Lightroom at all (at least through ordinary means). How often have you taken a photo with just a slight error in composition, where you wish you could include just a hair more information on one side of the crop or another? Lightroom users, as well as Nikon Capture NX users, may never realize that the underlying RAW photo actually held that data all along. Even though the distortion looks unsavory in certain cases, I would prefer at least the option to disable corrections, as has been the case with Lightroom and Nikon cameras in the past.
12. Chromatic Aberration
The Nikon Z 24-70mm f/4 S has hardly any visible chromatic aberration, even when left uncorrected. It takes up just a pixel or so at most, a small enough amount that automatic correction in post-processing software will rarely leave any detectable traces. Here is a graph showing the focal lengths and apertures with the highest levels of lateral chromatic aberration (red/green fringing):
The following 100% crop is a worst-case scenario – extreme corner, 36mm, f/4, sharp-edged subject. Even then, chromatic aberration is minimal:
Even more importantly – since it’s harder to correct – is that the 24-70mm f/4 has almost nonexistent levels of longitudinal chromatic aberration (color fringing in out-of-focus regions). This can be a major problem in some lenses, harming the quality of bokeh and making defocused lights look strange. The sample photos in the following section demonstrate practically nonexistent longitudinal chromatic aberration.
Normally, a midrange f/4 zoom isn’t ideal if you want blown-out backgrounds with beautiful bokeh. You will want to be at 70mm and f/4, and ideally focused fairly close, in order to have a strong out-of-focus background anyway. When you meet those conditions, is the Nikon Z 24-70mm f/4 S up to the task? Let’s ask Chester:
Chester says yes.
And here are a couple more sample photos if you are not convinced:
Bokeh is in the eye of the beholder, but I like how the images above look.
14. Focus Shift
In our testing, we found practically no focus shift – change in focus when adjusting aperture – with the 24-70mm f/4, regardless of focal length. The levels were negligible, perhaps even nonexistent. This is not unexpected for an f/4 lens (usually more of a problem on wide-aperture primes), but nonetheless is encouraging to see.
15. Focus Breathing
Nikon’s promotional material made an effort to point out that this 24-70mm lens has very minimal focus breathing – change in focal length when focusing. This is not particularly relevant to photographers, except in extreme cases (like the early Nikon 70-200mm f/2.8 VR for F-mount, which had excessive focus breathing). However, for videographers, it can be a significant problem. The reality lives up to Nikon’s claim, though; this lens has only a very small amount of focus breathing, enough to be irrelevant for most users.
16. Ghosting and Flare
For landscape photography, one of the most important overlooked factors in lens performance is flare. In backlit situations, some lenses have excessive internal reflections that appear in the photo as ugly blobs. Other lenses will drastically lose contrast in what is known as “veiling flare.” The Nikon Z 24-70mm f/4 S has some of the lowest flaring I have seen in a zoom lens, even when the sun is directly in the frame. I have only been able to get flare in a few isolated real-world cases, and even then it was not objectionable. For example, there is only a tiny green flare to the top-left of the sun in the image below, and this is about the worst I’ve seen so far:
Note that the rest of the image is extremely high in contrast, meaning there is very little veiling flare. Try as I might, I couldn’t get anything worse than this in a real-world image. The 24-70mm f/4 just has very impressive flare performance.
17. Starburst Performance
Because of the 24-70mm’s 7-blade aperture, you will end up with 14-point starbursts/sunstars in your photos. The starburst overall is quite well-defined with this lens, although individual blades are wider than on most other Nikon lenses. This leads to a rather unique look to starburst effects:
Personally, I like the look. When I first posted this image, some readers disagreed. It’s all a matter of taste. Maybe I’ll change my mind after spending more time with this lens and getting used to the effect, but for now I leave you to make up your own opinion.
With some lenses, pinpoints of light in the corners will blur into a pattern known as coma, especially visible at wide apertures. This is mainly relevant for something like astrophotography, although some nighttime cityscapes also apply. It is not usually something that photographers care about when their lens has a maximum aperture of f/4. However, with the relatively low number of Nikon Z lenses released so far, there is a good chance that early Z-system users will adopt this lens for astrophotography. If that applies to you, I am happy to report that the 24-70mm f/4 S has practically no coma, as you can see from the sample image and crop below:
On the following page, we compare the Nikon Z 24-70mm f/4 versus two of its F-mount competitors in terms of sharpness.