At least on Apple TV, you absolutely do need to occasionally change Lumagen’s DTM settings depending on content. It’s really just DynPad from my observations, and not a big deal. It takes about 2 seconds at the start of a film. It’s tied to the Apps on ATV. All iTunes content is consistent, but sometimes on Netflix, Amazon, or HBO, HDR content will require tweaking to DynPad or MaxLight. No question about that.His screen is larger than yours because he is zoomed out to fill, so the pixels are slightly larger on his screen than yours. His screen is roughly the equivalent of a 133" diagonal 16x9 screen.
Also, with regards to set and forget, the only reason one would need to change a setting on the Lumagen tone mapping is because Lumagen did a change to how it works and settings need to be reconsidered based on improvements to processing. Once the proper settings are in place, the need for changing is nearly 0. This is definitely NOT the case with the JVC tone mapping. It is quite good, but it still requires somewhat regular intervention and even with that it still struggles with quite a bit of content that doesn't so much as cause a blip with the Lumagen tone mapping.
Unless you set MaxLight to a low value, so that all content looks good. But if you do that, you are ‘leaving ”light” on the table’, as you can get more range on certain content.
Example: Set MaxLight to the scene in The Meg so there‘s no clipping.
Then watch an iTunes HDR film, like Ford vs Ferrari, and it looks great.
Then watch an Apple TV+ series like Amazing Stories, and it’s too dark. Dropping DynPad from 5 to 2 usually does it; on rare occasions I will drop MaxLight.