Bug 407246

Summary: Not possible to choose bright colors for onion skin for HDR animation
Product: [Applications] krita Reporter: Tiar <tamtamy.tymona>
Component: HDRAssignee: Krita Bugs <krita-bugs-null>
Status: CONFIRMED ---    
Severity: normal CC: griffinvalley
Priority: NOR    
Version: nightly build (please specify the git hash!)   
Target Milestone: ---   
Platform: Microsoft Windows   
OS: Microsoft Windows   
Latest Commit: Version Fixed In:
Attachments: Example animation

Description Tiar 2019-05-05 18:13:17 UTC
Created attachment 119855 [details]
Example animation

SUMMARY
Because Rec 2020 linear color space is both linear and allow for values higher than 1.0 (which are not clipped to 1.0, but shown properly), onion skin isn't that helpful on HDR or linear animations. It looks dark and doesn't really pop up as it does on my non-HDR laptop (which has a much lower grade display).

It looks like the reason for that is the color selector that doesn't allow for anything else than 8bit integer or values bigger than 1.0.

SDR animation isn't in a better situation though, because all SDR content is clipped to 80 nits, which is very low. But because there is nothing more bright than that on the canvas, it still somewhat work.


STEPS TO REPRODUCE
1. Make an animation using white circles. (Use HDR setup.)
2. Turn on onion skin.
3. Make sure the colors used for onion skin are the brightest possible red and the brightest green.

OBSERVED RESULT
Onion skin is rather dark, the contrast is not enough.


EXPECTED RESULT
Onion skin in 100% opacity and 100% of tint should be bright and pop out out of the image.


SOFTWARE/OS VERSIONS
Krita version: 4.2.0-pre-alpha (git fb08951)
Windows: 10
Qt Version: 5.12.2
Comment 1 Tiar 2019-05-05 19:29:06 UTC
Note: with lower values of tint it's possible to get HDR values in onion skin (check the included image with 0% of tint, it stays bright white).
Comment 2 wolthera 2019-09-21 15:58:31 UTC
This is also because these values are stuck in QColor sRGB.