Is Krita ready for HDR painting? | Hacker News Reader

Is Krita ready for HDR painting?

notes.ericjiang.com

30 pointserjiang6 comments

I talked to the Krita devs about adding HDR support to get Krita to be used in VFX, while I worked at DNeg in 2007/2008.

They didn't see the point/understood how this could be important, at the time.

Why would you want to do HDR painting?

Games, TV, Movies, other media that have digital artwork, all can render within a High Dynamic Range. If you produce artwork for those media, you would likely want to be able to match the capabilities.

But in that case does artwork made for HDR render well on non HDR screen or do you need to do the double amount of work to support both?

There aren't yet that many people using HDR screens. Even 4K is still kind of a niche in most parts of the world as most people don't replace their TV more than once every 10-15 years and when it breaks they aren't necessarily ready to pay a premium for a quality they haven't experienced yet.

It is always the same issue. Why buying better stuff if there is no content and why make content if there are so few users? [1]

[1] the answer is porn.

Display technology will continue to improve like audio hardware has over the decades. We haven't matched the human eye yet.

Cameras are shooting 12-25 bits of dynamic range. Displays can't yet render this, but the data is being captured and better reflects what the eye can see as it adjusts looking around a scene. This gives a lot of latitude when processing RAWs (sensor data) to render out a final image in a chosen format (Currently commonly SRGB 8bpc but moving to 10bpc 709/2020)

No reason paintings or created works couldn't also fill out at least a ~24 bit dynamic range similar to audio (Hence the move to 10bpc, which gives roughly ~1.07e9 (2^10)^3 possible colours compared to ~1.67e6 (2^8)^3)

In painting this would let you have a lot more contrast before blowing out a highlight (hitting the digital limit in brightness representation and clipping or losing information), and a proper tonemapping curve combined with dithering can fold this down for lower capability displays. This also gives you a lot more range to work with when digitally colour mixing.

A similar thing already happens with 3D rendering workflows in Blender/C4D/Maya/etc. where an output curve is applied for tonemapping and colour correction.

This lets you work in an unconstrained space for processing/creating and then incorporates a mastering/release specific step for rendering out to a given display format. The great part is, as technology improves the original work can just be displayed as is. (Think about the progression from wire recording -> tape -> cassette -> CD -> direct master renders sold in lossless file format)

In my case, I wanted to edit some HDR environment maps. They are a 360deg image of the environment used for 3D work. They need to be floating-point so that arbitrary brightnesses can be captured and used to calculate the lighting in the scene correctly.

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