There have been reports that the new Nikon Z6 III may have a more limited dynamic range than the old Z6 II. This observation was made by William Claff at Photons to Photos, who do in-depth testing of camera sensor performance and many others. Claff’s findings show that the Z6 III maxes out at 10.44 EV of dynamic range at ISO 100, compared to the Z6 II’s 11.26 EV at the same sensitivity. The Z6 III continues to trail its predecessor by 0.6-0.7 EV all the way up to ISO 800, where the two cameras perform very similarly:
Read more: Nikon Z6 III review
Now Claff obviously knows his stuff and has been testing sensor performance for years, so I’m not going to criticize his results or testing methodology. However, I can say that when I tested the Z6 III in the lab, I found that (contrary to Claff’s results) the dynamic range of the Z6 III was almost identical to that of the Nikon Z6 II at lower sensitivities, even though the new camera fell behind. previous generation by 0.5-1EV at ISO 6400 and above.
While this is surprising and disappointing, in my opinion the more notable difference between the two cameras is their signal-to-noise ratio – or how much image noise each camera produces at a given ISO speed. In our signal-to-noise ratio test, I found that the Z6 III and Z6 II generate very similar noise levels at lower sensitivities, but at ISO 1600 the new camera begins to produce noticeably noisier images than the Z6 II, and the trend continues. up to ISO 25,600 – our highest tested sensitivity.
And we’re not the only ones who’ve noticed that the Z6 III produces noisier images at higher ISOs – check out this detailed image noise comparison between it and the original Z6 from YouTuber Test Cameras:
Watch
While you’d be forgiven for assuming that the new camera will perform better in every test metric than the camera it replaces, that’s often not the case. More often than not, a new camera model with a higher megapixel count than its predecessor often produces a lower signal-to-noise ratio because cramming more pixels onto the same size sensor—whether APS-C or full-frame—makes each pixel smaller, less sensitive to light, and therefore more prone to generating noise.
But in the case of the Z6 III, its 24.5 MP resolution is identical to that of the Z6 II. The difference here may be more in the new partially stacked construction of the Z6 III sensor. Again, this is unproven speculation, but if a partially stacked sensor improves sensor readout speed for faster sequential shooting and reduces rolling shutter distortion, it may also have a detrimental effect on image noise and dynamic range. This is also supported by the sensor results on Photons to Photos, which generally show dynamic range performance from stacked sensors to be slightly lower than equivalent, non-stacked chips.
The best camera deals, reviews, product advice and unmissable photography news straight to your inbox!
I can’t give you a convincing explanation as to why a folded sensor would compromise image clarity and dynamic range, but I doubt it’s due to the design of the folded sensor itself. Simply layering sensor elements does not have to hinder image quality. Rather, using this design to increase sensor read speed is likely to be the culprit, although logically it doesn’t really contribute either. To capture a single still image, the sensor in the Z6 III uses the same (or very nearly the same) number of pixels as the sensor in the Z6 II. Both sensors have identical dimensions, resulting in identical pixel sizes. If the image is then taken at the same shutter speed and ISO, both cameras should produce very similar noise levels and dynamic range, assuming the Nikon image processing is also comparable. And yet our lab test results agree with those from other testers: The Z6 III doesn’t fare as well as the Z6 II (or even the original Nikon Z6) in terms of dynamic range and image clarity, so the increased sensor readout speed remains the most obvious cause.
But before you rush off to return your new Z6 III, let’s “slow down” for a moment. The differences in image quality between the two Z6 models highlighted in our lab tests and William Claff’s model are relatively small. In our case, we’re testing with all high ISO noise reduction disabled and all dynamic range enhancements turned off to keep the playing field level. When using these systems in a more “real world” setting, would you really be likely to notice such subtle differences in image quality if you weren’t deliberately looking for them? It’s unlikely.
Then when you consider the benefits a higher read speed can bring for increased burst speed, higher video resolution at a faster bit/frame rate, and other image quality improvements such as reduced rolling shutter distortion; many would argue that this increased versatility of a hybrid camera is worth the small trade-off in noise and dynamic range.