Ninja V C-Log 3 Cinema Gamut

Don’t Use C-Log 3 / Cinema Gamut on the Atomos Ninja V

How to get the best possible 4K video quality with the Atomos Ninja V and Canon C-Log (and what you should absolutely avoid)

Earlier this year I posted a video to my YouTube channel demonstrating how to setup the Atomos Ninja V monitor to record video externally from the Canon EOS R5 and R6. In that video, I mentioned that 4K video recorded externally on the Ninja V appears virtually identical to 4K video recorded internally on either the EOS R5 and R6.

And for the most part, that remains true, as evidenced by the following comparison shot using C-Log BT.709. 4K internal video on the left, 4K external video on the right.

C-Log 3 BT.709 Internal on the EOS R5 (Left) / C-Log 3 BT.709 External on the Atomos Ninja V (Right)

But since I made that video, Canon updated the firmware of the R5/R6 to include support for C-Log 3 and the Cinema Gamut color space. Great news for both cameras, but the Ninja V does not render Cinema Gamut correctly.

For example, take a look at the following comparison. C-Log 3 Cinema Gamut recorded internally on the left, C-Log 3 Cinema Gamut recorded externally to the Ninja V on the right.

C-Log 3 Cinema Gamut Internal on the EOS R5 (Left) / C-Log 3 Cinema Gamut External on the Atomos Ninja V (Right)

The colors in the Ninja V footage appear oversaturated, and there is a noticeable skew towards yellow. You can especially see the saturation push in the magenta, purple and green color chips, and the amount of yellow that has been pushed into the color of the table at far right.

I spoke with Atomos support about this in October, 2021 and they said this was a known limitation with the Ninja V. How long this has been a problem, or when/if it will be resolved, I’m not sure.

What I do know is that (for now) it’s best to avoid C-Log 3 Cinema Gamut when recording externally to the Atomos Ninja V. C-Log 3 BT.2020 and BT.709 are fine, as is C-Log BT.709 (as demonstrated earlier) on the Ninja V, but Cinema Gamut will cause a lot of headaches in post when color correcting footage.

Video

Here is the “Complete Setup in 5 Minutes” video for the EOS R5/R6 and the Atomos Ninja V.