Originally Posted by NxNW
To quote Bill Clinton, it depends what "is" is.
Let me explain what I meant by my statement:
Option 1: Set the UB820 to output HDR; set the TV to HDR (which would use ST.2084 EOTF and BT.2020)
Option 2: Set the UB820 to output SDR/BT.2020; set the TV to the same settings as Option 1 other than changing the EOTF from ST.2084 to Gamma 2.4. Keep the same peak luminance as well as colour space (BT.2020).
Option 3: Set the UB820 to output SDR; set the TV to SDR mode (100 nits peak, BT.709)
In terms of the end result (what the user sees on the screen, not what the signal "looks like" to the TV), Option 2 should look
substantially the same as Option 1 (which is unquestionably HDR), whereas Option 3 is unquestionably SDR. (I'm focusing on the D
ange as in SDR
, aside from the colour gamut).
SDR2020 produces a signal in an SDR format. The resulting image will "look right" on a display that can go brighter than 100 nits and has a large color gamut. So in that sense the viewing experience "is" HDR. But the signal "is" SDR.
Actually you’re better off using BT.709 if your display does not have a BT.2020 mode, even if it has a “wider gamut”. BT.2020 uses completely different colour coordinates and the colours will all be wrong if the display expects BT.709 or DCI-P3.