While grading my most recent S-log3 HDR video, I realized I’d failed to reduce brightness levels down to proper values in my previous ProRes RAW HQ HDR sample. In both videos, I’m wearing an orange cap and black jacket and sitting in a dark room a few feet away from a window on an overcast day.
With the help of the HSL qualifier, we see that the brightest pixels are in the windowsill and the alpha insignias on the cap and jacket.
If we want to preserve every last bit of texture in the threads of the alpha insignias and in the windowsill, we’ve got to maintain brightness below 100 nits for sure. If we’re willing to lose a little detail in the shiny threads in order to more accurately reflect what our eyes see in real life, we can push a little further. Which is why the brightest highlights measure no more than 200 nits in the waveform monitor of the NLE.