Originally Posted by jpiddy
What is the benefit to more nits on screen with open iris if it also raises the black floor? Brighter highlights, I assume, but at the cost of raised blacks and reduced contrast. It seems like a properly tone mapped source would benefit most from higher contrast. Seems like most calibrates/pros on the forum recommend open iris or max light output for HDR so I’m sure that I’m missing something.
The main benefit is less highlights compression. With 125nits on screen, you can watch more scenes exactly as intended, with zero tonemapping.
Open iris is recommended for most sources that don’t do dynamic tonemapping ( UB900, Oppo, UB900 etc), as they use the same tonemapping for the whole film.
With madVR and the Radiance Pro, you can actually have a lower target overall because each scene is optimized with an optimal brightness factor.
But it’s still a trade-off, especially with the DI in its current state.
The raised black floor is mostly visible on fade to black. With most content, you won’t notice it.
The native goes from 30,000:1 fully open to 40,000:1 at -8. Again, not a very significant difference. Perceived contrast is about the same.