Thanks to this thread I did some experimenting with my PS4 and OLED B7. Things I've learned:
- Tonemapping in HDR Game Mode is almost the same as HDR Cinema. It preserves detail in bright areas but is overall dimmer. HDR Standard clips brightness instead. The sun in SotC will produce just a giant patch of super bright sky, while on the other modes you can see it shining through the clouds.
- The Witness seems to have exactly the same problem as Monster Hunter: there are no blacks in HDR. Even the darkest cave is only gray, while in SDR the same spot looks pitch black.
- Testing HDR Standard in the Witness, I noticed image retention for the first time on this TV, after looking at a puzzle panel for only 10 seconds. This game is an extreme case due to its stark color contrasts, but considering you can look at puzzles for 15 minutes easily, you can see there's a reason for Game mode not being as bright.
- Tonemapping in HDR Game Mode is almost the same as HDR Cinema. It preserves detail in bright areas but is overall dimmer. HDR Standard clips brightness instead. The sun in SotC will produce just a giant patch of super bright sky, while on the other modes you can see it shining through the clouds.
- The Witness seems to have exactly the same problem as Monster Hunter: there are no blacks in HDR. Even the darkest cave is only gray, while in SDR the same spot looks pitch black.
- Testing HDR Standard in the Witness, I noticed image retention for the first time on this TV, after looking at a puzzle panel for only 10 seconds. This game is an extreme case due to its stark color contrasts, but considering you can look at puzzles for 15 minutes easily, you can see there's a reason for Game mode not being as bright.