How to Expose N-Log for the Nikon Z6

How do you expose N-log correctly for the Nikon Z6 (AmazonB&H)? Watch this video:

What is N-log?

Easiest way to explain is with an example. Imagine an image where you wished you had underexposed because the sky blew out, or if you don’t have shadow detail because the blacks are crushed:

In color grading you would bring down highlights and bring up shadows, hoping for the best:

That’s exactly what the camera does in the sensor, it brings down the highlights and raises the shadows so at least the information isn’t clipped. The downside is – you reduce contrast, the image looks flat:

In color grading, it is your job to bring back the image once again:

With higher end cameras like the Alexa, Red and so on, they provide you an official LUT that works like magic.

Guess what? Nikon doesn’t give you any such thing.

Thankfully, Nikon did publish some kind of white paper on N-log, but sadly, it is bereft of important information that should have been included.

Characteristics of N-log

This is the unofficial N-log curve, as measured by me on the Nikon Z6 (AmazonB&H):

Important: The theoretical total adds up to 14.3 stops, not 15.3 stops.

All you have to know is middle grey is at 35 IRE. So if you put an 18% grey card and expose for it, the IRE value will read 35.

The really shitty part of the Nikon Z6 is, you don’t get an in-camera meter to expose for the grey card, so you must use an external recorder with a waveform or false color tool, as I show in the video.

Black is at 7.5 IRE roughly. 90% white falls at about 61 IRE. I did these tests for different ISOs, and I won’t bore you with all the tests, just the results – what you need to expose N-log in the field.

How to expose N-log

Just follow these steps:

  1. Custom White Balance! If you get this wrong from shot to shot, they won’t match.
  2. Select the following settings in HDMI:
    • 10-bit 4:2:2
    • Full Range
    • N-log
    • View Assist: On
  3. Native ISO of 800 (you can go to ISO 6400 without much penalty)
  4. Keep anything important details above 20 IRE
  5. Keep skin tones below 85 IRE. That’s roughly 2 stops below clipping. This includes specular highlights. Ideally, you want to keep skin tones below 70 IRE generally speaking.
  6. Expose normally. You can do this because of the great low light ability of this camera. You don’t really have to overexpose like you do with other cameras that only give you compressed log. Still, there’s no harm in overexposing by a half a stop to one full stop with this camera.
  7. Use Zebras to help you with highlight clipping and skin tone clipping.
  8. Use the False Color tool and Waveform for perfect skin tone exposure.
  9. The color space for N-log is Rec. 2020.
  10. Even though N-log has a theoretical maximum of 14+ stops, in practice you only get about 12 stops. With 12-bit RAW, you will get the maximum possible dynamic range. N-Log is the next best thing.

You don’t want to worry too much about precision, because in the field, you won’t have the time to really stress about getting it right, especially when you have to match shots in editing.

Differences between S-Log3, V-LogL and N-log

Here are the differences between the three log profiles:

Levels

S-Log3

V-LogL

N-Log*

Black (0%)

3.5

7.3

7.5

Middle grey (18%)

41

42

35

White (90%)

61

61

61

*As measured by me, specific to the Nikon Z6. Nikon only published middle grey (18%) at 35 IRE.

Does this work for the Nikon Z7?

Even though N-log values are the same for the Nikon Z6 (AmazonB&H) or Nikon Z7, it doesn’t mean you can use the precise IRE values for the Z7, due to differences in dynamic range, color and noise characteristics. Therefore, I urge you to test the Z7 and find your upper and lower limits.

It won’t be too far from the Z6, but it wouldn’t be accurate to use the values from the Nikon Z6 for the Z7.

That’s it for exposing N-log!

The second part of the problem is grading N-log. Once you know how to grade N-log, you’re all set, and you can get better dynamic range and cinematic videos than most people. Please sign up if you haven’t already, and get that video and more delivered to your inbox:

Exclusive Bonus: Download my camera settings and 7 cinematic custom picture controls for the Nikon Z6. Setup your camera for cinematography, ready to shoot.

And, get bonus videos - How to expose and grade N-log, and How I have tweaked my favorite picture control for video - delivered to your inbox!

 

11 replies on “How to Expose N-Log for the Nikon Z6”

  1. Awesome series of articles! Thank you!
    My Atomos Ninja V (OS 10.01) shows a scale of 0 to 1600 in the waveform or parade, I believe these are nits (not documented!?) and not necessarily equal to IRE in the case of HDR. How do you get your Shogun to show 0 to 100 IRE?
    Also, using the VLogL LUT – wouldn’t that clip the highlights at 81IRE or over aggressively remap them?
    False colour works well ?

  2. Thank you so much, Sareesh! I have had my Z6 for a while now, but I was still somewhat clueless when it came to recording with NLog. That was until I found your guides! However, I get this flickering on my monitor at certain ISO values. Should that be a concern?

    1. You’re welcome. Use the shutter speed/flicker reduction in camera to eliminate flickering.

  3. Absolutely great help from You. A big thank you from Germany and the Philippines. I just bought my Z6 and there is really almost no usable advice in the internet about the Z6. All either fanboys or sponsored stuff and not constructive input like yours. I am looking so much forward for your color grading because i am now struggling with getting it to Rec709 without noise in my red shirt. Or maybe you know why i have those noise in their.

    1. Thank you! You might be underexposing, otherwise I don’t see any reason for noise in the red channel.

  4. Thanks so much…watched this the first time and then went back with my Z6 in hand (and your settings installed) and went step-by-step. Following your instruction is getting me faster up to speed than anything else. Will continue to support your efforts – thanks again.

  5. Nicely put, Sareesh. I did Geof Boyle’s style test to determine ISO rating, etc. for Nikon Z6. You can check it here: https://vimeo.com/322204952. Basically for interiors and situations where you need a better response/balance in the shadows it would be advisable to rate the meter at 400 ISO or even 320 (while the camera is set at ISO 800) to shift the range towards cleaner shadows. But that’s true for many high end cameras as well. I’m almost done on Alexa based monitoring LUTs which really show how good this camera is for skin tones and color overall. Message to everyone: please DO NOT USE ATOMOS provided REC709 LUT when monitoring video from Z6. It’s awful and doesn’t do justice to the camera’s capabilities! I’ll make sure to share the basic LUT for everyone to use.

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