Nikon Z 9 N-RAW Lab Test (FW 3.00) – Rolling Shutter, Dynamic Range and Latitude

Lab Test

by Gunther MachuJanuary 31^st, 2023

Last year, the firmware V2.0 brought 8.3K N-RAW (internal) recording capabilities to the Nikon Z 9 and we immediately asked ourselves, how this new feature will impact the lab test results we published back in December 2021. Curious to know more? Then read on …

[UPDATE June 23rd 2023]
After firmware update V4.00, our updated lab test results are as follows for N-RAW, H.265 and ProRes 4:2:2 HQ (numbers are stops of Dynamic Range):

You can find all results for fimware V3 and FW V4 in the Camera Database.

[Original article continues]

As my colleague, Jakub said in an article on the firmware V2.0, “Perhaps the most impressive new feature of the firmware v2.0 is the addition of the in-camera RAW video formats – 12-bit N-RAW video at up to 8.3K (8256×4644) 60p as well as internal 12-bit ProRes RAW HQ up to 4.1K 60p. In regards to the infamous RED patent, I am not entirely sure how Nikon managed to include internal ProRes RAW when so many other camera manufacturers needed to remove the codec from their devices, but it is definitely good news”.

We used firmware version V3.00 to test N-RAW on the Nikon Z 9. (Current camera version is 3.01 which brings small improvements that are not related to video picture quality). We did not test ProRes RAW – for one, it is limited to 4.1K and secondly, you cannot import it natively into DaVinci Resolve – hence, we discarded this option altogether. Thanks again to my dear colleague Florian, who helped with shooting this test.

So without further ado, let’s jump into the results of our Nikon Z 9 N-RAW Lab Test!

Nikon Z 9’s Rolling Shutter in 8.3K N-RAW Full Frame

There’s nothing new to report on this front, as we get exactly the same result as with Z 9’s other full-frame codec options:

As I wrote back then, that is about 1ms better than the Canon EOS R5 and about 2ms better than the Sony A1. The king of the castle for mirrorless full-frame cameras in this price bracket is still the Sony a7S III with an 8.7ms rolling shutter in full-frame mode. On top of the list is the Sony Venice 2 with less than 3ms.

Nikon Z 9’s Dynamic Range using N-RAW at ISO800

When importing the Nikon N-RAW files into DaVinci Resolve 18.1, we have the following options in the Camera Raw tab (see image below). Basically, all you need to do is expand the image values using “Lift” and “Gain” to get a bit more contrast, set the color space to Rec709 (other options are P3 D60 and Rec2020), and the Gamma to N-Log (with Gamma 2.4, 2.6, Linear and Rec709 as other options) and you are done.

If you are not familiar with how we test dynamic range, please head over here. The following waveform is obtained when shooting the Xyla21 chart (setting “Lift” and “Gain” back to “0”):

12 stops are visible above the noise floor, similar to our earlier findings. It’s a bit of a pity that there is no newer N-Log profile available. N-Log, as it is now, is very flat in the shadows, almost cutting off the noise floor.

Imatest calculates 10.2 stops at a signal-to-noise ratio (SNR) of 2 and 11.9 stops at SNR = 1. Also, beyond the blue line tagged with “11.9” in the middle graph below, there is maybe one additional stop visible. Hence, about 13 in total.

N-RAW is obviously using less signal processing (like noise reduction) than the other internal codec options we tested earlier, which is good. Noise reduction can always be added in post-production. Therefore at first glance, the IMATEST results are worse than, for example, when using H265 8K internally (11.6 stops at SNR = 2 and 12.7 stops at SNR = 1).

However, there is a big advantage when shooting N-RAW, which will become very obvious in the next section: the latitude test – N-RAW is recorded at 12 bits!

EDIT: some readers (Thatcher Freeman and others) suggested that potentially a color space transform in DaVinci Resolve from N-RAW using linear to another log profile would circumvent the deficiencies in the shadows of N-Log. I tested that, using “Linear” as the gamma in the Camera Raw tab and Rec709 as the Color Space, and also using that as an input in the color space transform node. Then setting the output to ARRI Wide Gamut 3 and ARRI LogC3 and developing the files in IMATEST. Here is the result:

As can be seen above, IMATEST calculates slightly higher results (SNR = 1 is now 12 instead of 11.9 stops, slope based DR = 13.4 instead of 13.2), while SNR = 2 is the same 10.2 stops. Interestingly (due to the ARRI LogC3 Gamma), shadows are not cut off so abruptly – there is about 1 more stop in the shadows, seen in the middle diagram above the blue curve labelled as “12”. In the latitude section below I have added one image using ARRI LogC3 as well.

Nikon Z 9’s Latitude result shooting N-RAW at ISO800

As written before, latitude is the capability of a camera to retain detail and colors when over- or underexposed and pushed back to a base exposure. This test is very revealing, as it pushes every camera to its absolute limits – not just in the highlights but also in the shadows.

Our studio base exposure is (arbitrarily) chosen as having an (ungraded) luma value of 60% on the forehead of our subject, in this case, my colleague Nino on the waveform monitor.

Now, the first positive surprise: with N-RAW, we can go to 4 stops of overexposure and bring back the image to base exposure. As you can see below, in the waveform the red channel on Nino’s forehead is fully intact (before bringing it back to base exposure):

With N-Log and internal 10bit H265 8K recording, we could only overexpose by 3 stops.

Now, let’s underexpose and bring back the image. We do this by closing the iris of the lens from f1.4 to f2, f2.8 until f8, and then we increase the shutter speed from 1/25s to 1/50, and so on.

In post, using DaVinci Resolve 18.1 there is another very positive surprise. The “Exposure” slider in the Camera Raw tab goes from +5 to -5. So, bringing back the over- or underexposed images is super easy.

Here is the 3 stops underexposed image, brought back:

A fine noise starts to appear, but the image still looks really good without any further editing. Now, this is already one stop better than the results we got one year ago with internal N-Log 8K H265.

Because N-Log is so flat in the shadows, there is almost no code value difference between the stops. Shooting 10bit H265 internally in our first lab test, even 10bit did not provide enough code values between the stops leading to banding, and therefore a rather bad latitude result of only 6 stops.

With 12-bit N-RAW, there is no banding visible so far. Let’s move to 4 stops under, pushed back:

Noise kicks in, which can be removed by noise reduction, but as you can see from the screenshot below, a rather high chroma noise (spatial) and temporal noise reduction is used:

Other than that, all is good. We are at 8 stops latitude, which is already the best result we got so far for consumer full-frame cameras in this price bracket – with the Panasonic S1H, S1, and S5 as well as the Sony A1. That is 2 stops better than with the 10-bit internal 8K H265 codec. That’s the power of RAW!

Now, the 5 stops under, pushed back image starts to fall apart – also adding a very greenish tint to the image:

Even heavy noise reduction in post cannot completely save it:

As can be seen above, we are already using a maximum of “100” for the spatial chroma noise reduction, and quite a lot of temporal noise reduction.

It still looks quite OK, however image details in the shadows (for example in the lower right-hand corner next to Nino) are fading away.

That gives a solid 8 stops of latitude performance, with some wiggle room towards 9 stops!

Edit: using the N-RAW “Linear” to ARRI LogC3 color space transform in DaVinci Resolve and applying noise reduction yields the following image:

A bit more pink in the image, less greenish, and a bit more contrast in the shadows – apart from that little to no difference.

Summary: obviously, a color space transform circumventing N-Log does not yield improved results unfortunately. Nevertheless, thank you to our reader Thatcher Freeman for pointing out a potential improvement path! We really appreciate this discussions with our readers in the comments section below!

Summary

With the inclusion of internally recorded N-RAW, the Nikon Z 9 really makes a huge leap forward. Not only does it show strong results in rolling shutter performance (as it did before), but it’s now also capable of recording 8.3K 12bit up to 60 frames per second. As expected, N-RAW is noisier because not so much internal signal processing is going on – leading to lower IMATEST results of 10.2 stops at a signal-to-noise ratio (SNR) of 2 and 11.9 stops at SNR = 1 (compared to internal 8K H265 N-Log).

But looking at the latitude results, the 12-bit combined with the power or RAW in terms of exposure adjustments make all the difference.

2 if not 3 stops more latitude compared to 10bit H265 recording bring it to the top of the list of full-frame consumer cameras with 8 stops of exposure latitude (with wiggle room towards 9).

Nikon has come a long way with the video features on their photo cameras, and it shows.

What do you think of this Nikon Z 9 N-RAW Lab Test and our results? Have you shot N-RAW on the Nikon Z 9? What are your experiences? Please share your thoughts in the comments section below.