What should the LLDV max luminance value be set to for most users?
For most users the default LLDV max luminance of 1000 nits works well.
Why do I have a red tint and colours that look over-saturated?
If you set the DV primaries to DCI-P3 and send LLDV to a display that has no DCI-P3 colour profile, the display applies a BT2020 profile instead, which makes colours more saturated and adds a red tint that is most visible on faces. The solution is to send BT2020 rather than DCI-P3.
My display supports DCI-P3 but my streaming stick only outputs RGB and YCbCr. Can I force DCI-P3?
When you set the LLDV primaries setting to DCI-P3, the source is told that the display wants DCI-P3 instead of BT2020. Even if the source has no DCI-P3 output option of its own, the Dolby Vision to LLDV tone mapping performed by the Dolby-provided software should output DCI-P3 colours. The Apple TV 4K has no DCI-P3 output option either, and it does send DCI-P3 colours when the DV EDID is configured for it.
How do I set an Oppo UDP-203 or UDP-205 to output LLDV instead of Dolby Vision?
In the Oppo HDR settings, set Dolby Vision Processing to Player-led. HDR can stay on Auto if you only want LLDV for Dolby Vision discs. If you want the player to convert SDR and HDR10 to LLDV as well, set HDR to Dolby Vision.
How can I tell whether an Oppo UDP-203 or UDP-205 is actually outputting LLDV?
Long-press the Information button on the Oppo remote and scroll down to Output Information. It should read Format: Dolby Vision and Colour Space: 12-bit. That confirms LLDV output.
For the controls themselves, see the DV section chapter. For the background on how Dolby Vision capability travels through EDID, see the Dolby Vision EDID guide.