ODT/DRT - ST2084/PQ @ 48 nits for Dolby Cinema 3D

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ACES 1.1 introduced the 108 nit PQ DRT/ODT, which works great for 2D Dolby Cinema grading in ACES. However, and forgive me if this is a total n00b question (I have searched this forum/google for similar questions), there doesn’t seem to be a simple, one-touch equivalent for grading in 3D at 48 nits in PQ. There are workarounds, but I was wondering if there’s an ACES-approved way of doing this, apart from “don’t go above 48 nits on your scope”? Thanks!

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There’s no 48-nit PQ ODT supplied by default but it’d be trivial to make one in CTL.
The real question will be how to get that in a form that you can easily use in whatever tool you’re using.
It would probably be fairly simple to get this in DCTL for use in Resolve, especially leveraging all the work that @Paul_Dore has done for the community.

How do you need the transform formatted? What tool(s)/software are you using?

Thanks Scott, we would need a Baselight DRT and ACES ODT in Resolve. Both currently have the P3-D65 ST2084 108 nit option, as per the ACES 1.1 update.

Hi there everybody! Has somebody tested the 108nits ST2048 odt in comparison to regular BT1886/Rec709 Gamma on an OLED Screen? Is there a visible contrast benefit to use the PQ Curve instead of the Rec709 curve in regards of percevied contrast? I am asking because I have more affinity towards a filmic low brightness look but with the added information in the low register/shadows.

Hi Roman, the 108 nit ODT is designed for theatrical screens, it’s always looked pretty dark when I’ve viewed it on reference monitors. PQ values are absolute, so you should still be able to achieve the same detail in the dark areas whether you use the 108 nit ODT or a 1,000 nit ODT, or whichever max brightness your monitor goes up to. You can keep things dark but use the extra dynamic range to push your speculars if so desired. That’s my view as an engineer, actual colourist opinions may vary…

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Thank you very much for your input! This is very useful information regarding the absolute values, and yeah it might be wasted potential to leave the higher registeres untapped. Depending on the content of course. The main question is still where the actual nit limit of a certain consumer monitor lies ( also depending on the window size ) and there the dynamic tone mapping starts. Is there a way to export Dolby Vision Files with included Metadata to set the monitor into dolbyvision mode? What can I do when I exported a mezzanin file by Resolve. How would I then go about delivering dolby vision content. I am not netflix or amazon ;), but as an independent video artist, would love to have tonemapped a frame by frame consistent interpretation of the PQ Curve in 12bit H265 content.

Netflix provides documentation on their required workflow on their website, which may give you a better understanding.
As far ad Dolby vision, it provides the metadata (scene or Frame) in the (your project) Resolve setup and transferred upon render as opposed to the static HDR10 metadata - if this is what you are asking.
Your settings i.e., ST2100- BT2020 set the EOTF/PQ telling the (Capable) Display how to emit / display the data it’s being fed.
OLED Televisions are just now hitting the market at 1000 cd/m2 levels affordable enough to the general public (LG’s C9, CX, Sony 900 & 950H) So the timing is right.

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Welcome James,
Thanks for your first post!

Steve T
ACESCentral Admin