Paper White - in HDR games
This article explains paper white from a gamers perspective. It's the least understood concept in HDR setup, and most games don't give us proper settings for it. At the end I will show how I estimate the paper white a game uses.
Games do not always call it paper white. Look for these names: Midpoint or Brightness Midpoint, or just Brightness / HDR Brightness.
What is paper white
Paper white (also called reference white or diffuse white) is the brightness of "normal white" things in the game. A white wall, paper, snow, bright daylight ground, and usually the UI and menus.
Paper white sets the overall brightness of the game — it's the brightest midtone a game will show. Everything below paper white is shadows and midtones. Everything above paper white is upper midtones — like clouds and sunlit surfaces, and above those the real highlights: the sun, fire, neon lights, reflections.
That's why paper white matters so much. It decides how bright the game feels, and how much room is left for highlights to pop.
How to set up paper white
There is no official standard for paper white in games. Some will say paper white is personal preference and depends on the ambient light in your room. That I agree with. But as gamers we need more specific guidelines than "set what you like".
So I use the HLG reference white values (from ITU-R BT.2408) as guidelines or starting points. They are made for broadcast, not games, but the idea behind them is exactly what we want: they scale paper white with peak brightness to keep the perceptual relationship between midtones and highlights. On a brighter TV we don't only want brighter highlights — we want to utilize our midtones too, so the whole image gets closer to real life brightness.
The HLG values:
You can also calculate it for your exact display here:
https://nikitamgrimm.github.io/hlg-reference-white-calc/
The logic is simple. On a 1000 nits TV, paper white at 203 nits leaves around 800 nits of headroom for highlights. On a 2000 nits TV, paper white at 343 nits keeps the same proportional headroom, but the whole game gets brighter. If you keep 203 nits paper white on a 2000 nits TV, the game looks darker in midtones than it should, and you waste your TVs capability.
"These are starting points, not rules. Games can handle paper white very differently — some have no paper white setting at all, some have a slider that changes more than just paper white, and some don't output the value the slider says. Personal preference matters too. Ultimately set up what looks most natural to you."
One important thing: I assume you play in a dark or dimly lit room. That's how HDR is meant to be experienced. If you play in a bright room, you might want to raise paper white to compensate — but that shrinks the distance between midtones and highlights, so bright objects lose their pop. And you lose detail in shadows in a bright room. HDR and bright rooms just don't go well together.
Most games don't have a proper paper white slider to let a 2000 nits TV owner, like myself, raise paper white properly. It's one of the biggest reasons I use RenoDX mods on PC.
How I find paper white in games
There is no software I know of that shows the paper white a game outputs. So I use an indirect method with Lilliums HDR analysis tool.
I look for a large, well lit, non-reflective (diffuse) white surface — facing away from the strongest light source, with no clouds, emissives or specular highlights in the frame. Full screen snow is perfect if the game has it. In such a scene, that surface should be very close to the actual paper white.
Be aware that many games use auto exposure (dynamic brightness adjustment), which can make the readings inconsistent.
I also measure the same surface at two different peak brightness settings. If the value doesn't change, the game has a fixed paper white. That's what most games do.
Snow is around 203 nits in both images, so paper white is 203 nits no matter the peak brightness. Paper white is 203 nits in most games, because that's the standard reference white in HDR content. Games keep it fixed and don't scale it for brighter displays.
In this image I looked at a white wall in Call of Duty Black Ops 7 to look for a paper white value. The area lit up by the bright lamp is 203 nits indicating paper white of 203 nits.
Disclaimer
I'm a gamer, just like you, not a developer, so I can't say exactly how a game handles paper white internally. My method is an estimate and my recommendations are written in plain terms to help gamers — not an exact science.