SOLVED: HDR minimum brightness is to dark on android phone

[Jasper Michal]

I have a number of 4k Blu Ray rips on my jellyfin server. They look great on my other HDR compatible devices (tv, Windows PC using mpv-shim), but on my pixel 6 pro dark scenes in most movies are so dark as to be unwatchable in anything other than a dark room. It's not a peak brightness problem, since brighter scenes and highlights like the sun or stars are as bright as you would expect from HDR.
For context this is using the jellyfin app integrated player and directplay.

The only way I can playback dark scenes at a watchable brightness without covering my head with a blanket is to force jellyfin to tonemap them to SDR (or use an external player that tonemaps them to SDR).

I'm aware this isn't necessarily a jellyfin issue since I get the same result playing the files in VLC (on my phone), but I'm at a loss and hoping someone here may have encountered this? Maybe some way of calibrating the screen to increase the minimum brightness?

[TheDreadPirate]

Whenever I watch HDR content I have to crank the brightness to max. Findroid has a quick gesture to do this. I don't recall if the official app has one.

[Efficient_Good_5784]

The Android app's native player has a setting to swipe up/down on the screen to change the brightness or volume. It's the same for some of the other 3rd party players like MPV or VLC.

Just swipe up on the left-side of the screen to get max brightness.

Also, what are the screen specs of your other displays (tv, Windows pc)? I looked up the screen your phone has. Your issue may be because your phone has an amoled display. The point of that type of display is to show actual black colors. And HDR (as its name implies) will show a big range from true darkness to 100% brightness. What you're looking for is to increase the floor at which the video will display dark scenes, which technically lowers the dynamic range of brightness (you can't push past 100% phone brightness to compensate for the lowered dynamic range), the opposite of what HDR is trying to achieve.

My phone has an oled screen, and I also at times can't see parts of a video when it has some dark scenes and I'm out in some form of daylight.

[Jasper Michal]

Thank you both for the insight, I think I figured it out. The computer monitor I'm comparing to is a QD-OLED with a peak brightness of 980 nits. My phone has a peak brightness 842 nits but I learned that apparently, it will only hit that if its increasesing the brightness automatically at the behest of the ambient light sensor. I.E., it only gets that bright in direct sunlight. Under normal circumstances, the peak brightness is 495 nits. So I thought I was comparing two screens of similar brightness, but in practice, I was comparing a brighter screen to a dimmer screen.