Focusing Characteristics
Few lenses focus as quickly and accurately as the Nikon Z 600mm f/4 TC VR S. Even among Nikon’s blazing-fast autofocus on today’s camera, this lens is in a different league. The only Nikon lens that focuses even better than this one is the Nikon Z 400mm f/2.8 TC VR S due to the f/2.8 maximum aperture, allowing it to work in lower light.
![](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/MV-Z9A-20230403-1388.jpg/w=960)
Even with the internal teleconverter, the focusing speed does not let up (unless the light is so low that f/5.6 causes problems for your camera). It didn’t feel any slower than using the lens without a teleconverter at all.
![Nikon Z 600mm f4_sample images__LVP8254-NEF](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/02/Nikon-Z-600mm-f4_sample-images__LVP8254-NEF.jpg/w=960)
The lens focused quickly regardless of which camera we placed behind it. You’ll see photos throughout this review from the Nikon Z9, Nikon Zf, and even the Nikon Z6. In a worst-case scenario – my old Nikon Z6, in dull light, with the internal teleconverter engaged – it felt like the Nikon Z 600mm f/4 TC VR S elevated the camera to unusual levels of focusing speed and accuracy.
![Nikon Z 600mm f4 TC VR S on Nikon Z6 at 840mm](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Nikon-Z-600mm-f4-TC-VR-S-on-Nikon-Z6-at-840mm.jpg/w=960)
![Nikon Z 600mm f4 TC VR S on Nikon Z6 at 840mm 100% Crop](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Nikon-Z-600mm-f4-TC-VR-S-on-Nikon-Z6-at-840mm-100-Crop.jpg/w=960)
Does this mean you’ll never take an out-of-focus picture again? Absolutely not. No lens is magical, and it still requires careful choice of your AF area mode, plus good reaction time. But the 600mm f/4 TC VR S approaches the best focusing capabilities that a lens can achieve.
Distortion
Distortion is generally irrelevant for exotic supertelephotos like this one – it’s not all that likely that you’ll be using this as your primary architectural photography lens. Nevertheless, we always test distortion in the lab for reference, and here’s how it measures on the Nikon Z 600mm f/4 TC VR S:
Regardless of the combination of teleconverters used, the lens never has particularly high distortion. The bare lens has no meaningful amount at all, and only with the built-in TC does it rise over 1%, with 1.40% pincushion distortion as measured in the lab. This is nothing to worry about at all.
Vignetting
The Nikon Z 600mm f/4 TC VR S has very minimal levels of vignetting. It’s a little worse as you focus further away, but even the maximum that we measure – 1.11 stops when using the bare lens at f/4, infinity focus – is no concern. Here are the charts as measured in the lab:
This performance is excellent, as expected. Supertelephoto lenses usually don’t have as much vignetting as wider lenses, but it’s still good to see here.
Lateral Chromatic Aberration
There is hardly any lateral chromatic aberration on the Nikon Z 600mm f/4 TC VR S as a bare lens. However, adding the teleconverters in various combinations can lead to more CA, which is not unusual where teleconverters are concerned. Here’s the chart:
This is one area where the built-in 1.4x teleconverter has a minor advantage over the external 1.4x teleconverter. The difference is quite small, though. If you’re shooting against strong backlight – such as an animal in a tree against the bright sky – it may be noticeable, but not by much.
Doubling up teleconverters (in any combination) increases chromatic aberration further. However, this is still a lot better than most supertelephoto lenses. In the past, we’ve seen well over 3.0 pixels of lateral CA when using a teleconverter on some lenses. By comparison, this lens never quite reaches 2.0 pixels, even when pairing two teleconverters together. Quite a good performance!
Sharpness
Everyone knows that the Nikon Z 600mm f/4 TC VR S would be a sharp lens. It comes with the territory when you’re spending $15,500 on such exotic glass. But how does it measure up in the lab, and what do you lose with the teleconverters?
To start, here’s how it performs at 600mm:
This is nearly perfect performance – as sharp as a tack throughout the frame, with f/4 being the sharpest aperture through most of the frame.
What about at 840mm? Here’s how the lens performs with the internal 1.4x TC, followed by its performance with the external 1.4x TC:
We’ve lost a little sharpness here, but much less than you might expect. The lens remains exceptionally sharp with either 1.4x teleconverter. The widest aperture is still the sharpest, and frankly, the results at f/5.6 here are within striking distance of f/5.6 on the bare lens. What an impressive performance with a teleconverter!
For what it’s worth, the two results above are extremely similar to one another. This is the same story as we saw in our Nikon Z 400mm f/2.8 TC VR S review – there is only a negligible sharpness benefit to the internal 1.4x TC compared to the external one.
While that may be surprising, I want to provide some context. About a year ago at Photography Life, we tested three copies of the Nikon Z 1.4x teleconverter (and three copies of the 2.0x teleconverter) and only kept the sharpest one of each. What you’re seeing above is therefore a best-case scenario with the external teleconverter. I don’t expect that the average Nikon Z 1.4x TC will perform quite as well as the average built-in teleconverter on this lens. But it looks like an optimal copy can match it, or at least come extremely close.
My takeaway is that Nikon’s external TCs – and their internal TCs – are simply about as good as a teleconverter can be. Therefore, the benefit of the internal TC over an external TC is not so much the added optical performance, but rather the added convenience.
Now let’s look at 1200mm. There are two ways to reach 1200mm on this lens: combining 1.4x teleconverters, or using the external 2.0x teleconverter.
These are some strikingly sharp results for doubling the magnification of a lens! Of course, it’s not as sharp as the bare lens, but 2x teleconverters never are. This is arguably the best performance we’ve seen on any lens when a 2x teleconverter is attached.
Which of the two ways to get to 1200mm is sharper? Neither – the results are totally interchangeable, within the margins of what the human eye can detect. (I found something similar when testing the Nikon Z 400mm f/2.8 TC VR S with its two different ways to reach 800m.)
That said, if you want to reach 1200mm and have both external TCs on hand, my recommendation is to use the 2.0x teleconverter, unless you have rigorously tested your own copy of the lens. The interaction between two 1.4x TCs and the lens is likely to be more variable and unpredictable than the interaction between a single 2.0x TC and the bare lens.
Finally, how does the Nikon Z 600mm f/4 TC VR S perform when you double up the internal 1.4x TC and the external 2.0x TC? Here’s what we measured:
I couldn’t believe my eyes when I saw this result. It’s barely worse than a typical lens at f/16! Seriously, there are plenty of lenses that don’t reach these numbers at f/16 as a bare lens. Getting this result with not one, but two teleconverters engaged – increasing the focal length of the lens by a factor of 2.8 – is unheard of. That explains the sharpness of the grizzly bear cub crop on the previous page of this review.
Early Access:
See all of our sharpness tests weeks (or months) before we publish the full review when you become a Photography Life Member. Photography Life Members can also access our Online Workshops, monthly photo critiques, Creative Landscape Photography eBook, and more. Thank you for supporting Photography Life – we are an ad-free website thanks to you!
Bokeh
Bokeh is another word for the qualities of the background blur in a photo. “Good” bokeh is completely subjective, since different photographers have their own preferences for how the background blur looks. That said, photographers commonly want their background blur to be soft, not distracting. Out-of-focus highlights that are round, uniform, and soft-edged are usually considered favorable.
The Nikon Z 600mm f/4 TC VR S has beautiful bokeh, not to mention an exceptional ability to throw backgrounds out of focus in the first place. The degree of out-of-focus blur that you can achieve with a given lens can be described with the size of its entrance pupil (focal length divided by aperture) – and the 150mm entrance pupil of the Nikon Z 600mm f/4 TC VR S is larger than that of any other Nikon Z lens. Even with the Nikon Z 400mm f/2.8, you’ll need to approach more closely to your subject if you want to get a shallower depth of field than the 600mm f/4 can achieve.
![Nikon Z 600mm f4 TC VR S Sample Image Bison](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Nikon-Z-600mm-f4-TC-VR-S-Sample-Image-Bison.jpg/w=960)
![Nikon Z 600mm f4 TC VR S Sample Image Bison Bokeh Crop](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Nikon-Z-600mm-f4-TC-VR-S-Sample-Image-Bison-Bokeh-Crop.jpg/w=960)
As with other lenses, the quality of the background blur diminishes a little when you attach a teleconverter. The edges of specular highlights become harsher, and the bokeh itself takes on some more texture. It’s not enough that I see any reason to avoid the teleconverters, but it is an effect you’ll notice from time to time. However, if the background is sufficiently out of focus, any negative effects of the teleconverter go away completely.
![Nikon Z 600mm f4 TC VR S with 1.4x TC engaged, Nikon Zf](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Nikon-Z-600mm-f4-TC-VR-S-with-1.4x-TC-engaged-Nikon-Zf.jpg/w=960)
In any case, it’s hard to find better bokeh than what the Nikon Z 600mm f/4 TC VR S can achieve. Images with out-of-focus backgrounds with this lens have a beautiful, luxurious quality to them. There is a little bit of cat’s-eye shape in the far corners at maximum aperture, but nothing distracting.
Backlit Conditions
The Nikon Z 600mm f/4 TC VR S has excellent coatings that help this lens perform to a very high standard in backlit situations. Supertelephoto lenses sometimes have high levels of veiling flare because of their complex constructions, but not this one. Even in the stress test below, the lens retains great contrast and the main subject remains a silhouette.
![Flare and Backlight Test Nikon Z 600mm f4 TC VR S](https://photographylife.com/cdn-cgi/imagedelivery/GrQZt6ZFhE4jsKqjDEtqRA/photographylife.com/2024/05/Flare-and-Backlight-Test-Nikon-Z-600mm-f4-TC-VR-S.jpg/w=960)
You can safely use this lens even in the most extreme backlit situations. Just don’t point it directly toward the bare sun, or you’ll quickly burn a hole in your camera sensor due to the lens’s high magnification.
The next page of this review dives into the sharpness numbers a bit more, with some comparisons against other lenses that Nikon users may be considering. So, click the menu below to go to “Lens Comparisons”:
Table of Contents