in RAW land, all this is very different if you use cinema DNG, jpeg2000, EXR, or RAW.
cinema DNG/ RAW is accessed directly right click source settings or in newer version, under master clip, exposure.
for EXR and jpeg2000, read below.
The only way I know of “accessing” rec. 2020 data natively in premiere is tricking it into thinking its HDR footage.
The new HDR lumetri interface only supports HDR within two separate containers – JPEG 2000 with a PQ (Dolby Vision/2084/Rec. 2020) curve(Dolby Vision Mezzanine files), and Open EXR.
So you’d have to transcode everything….
How to:
in scopes, switch to HDR
in lumetri color, click checkbox on HDR
you can now use HDR white and HDR specular
There’s a massive gotcha though. it disables input LUT’s in lumetri!
as a side note:
Premiere Pro’s J2K exporter now includes a 12-bit PQ option. When you select the RGB 4:4:4 12-Bit PQ option from the Chroma and Depth pop-up menu, a new drop-down list allows you to select the Color Space: Rec709, Rec2020, or DCI P3.
https://helpx.adobe.com/premiere-pro/using/whats-new-November-2015.html
and HEVC checking HDR renders log looking ST2084 gamma of rec. 2020
unless using SDR conform for non-HDR devices.