Meeting Summaries 

ACES Output Transforms VWG 

← Use sidebar to navigate to a particular meeting.
Use Cmd+F or Ctrl+F to search this page.

Meeting #16, April 16th 2021, 1pm PT


Alex Fry
Kevin Wheatley
Scott Dyer
Nick Shaw

Rémi Achard
Lars Borg
Chris Brejon
Sean Cooper
Francesco Luigi Giardiello
Jean-Michel Gilbert
Harvey Landy
Zach Lewis
Thomas Mansencal
Michael Parsons
Joshua Pines
Matthias Scharfenberg
Daniele Siragusano
Jed Smith
Troy Sobotka
Raymond Yeung

Meeting Notes

  • Kevin Wheatley: We're proposing meetings every other week (same time) to give people more time to do things.
  • Chris Brejon: Can they alternate with OCIO meetings.
  • Kevin Wheatley: There are multiple OCIO meetings. We'll take a poll. One thing we haven't discussed is people's monitors and viewing environments. What do people have access to.
  • Thomas Mansencal: And calibration state.
  • Kevin Wheatley: Even a simple diagnostic pattern like this one I made would help. It could be more complex. Many factors – flare, EOTF, RGB primaries, white point, environment. We also need one environment to be the reference for the tone scale. Existing ref is dark cinema. Is that the right, or is something in the middle better.
  • Joshua Pines: 2 things in favor of cinema as ref. 1. this is under the Academy of Motion Picture Arts and Sciences. 2. A cinema projector is something we can be confident is fairly consistent everywhere, calibration and surround.
  • Kevin Wheatley: Indeed, that is a key reference. But I wondered if the tone scale should be based on just that, or if a more office environment could be defined or taken from a standard.
  • NS: It might make sense to reference something in the middle, so you adapt up and down, instead of only up from the darkest.
  • Jean-Michel Gilbert: Starting from an average it might be easier for Dolby Vision metadata to adapt.
  • Thomas Mansencal: A brighter surround as a default might make sense because the way people watch movies has changed. CG artist don't tend to work in the dark either.
  • Joshua Pines: Our displays are reference standards. End users' displays are uncontrolled. sRGB vs 2.2 gamma etc. Daniele has a great webinar on that. Avoiding sRGB conundrums is preferable. When we are evaluating shadow roll off in the tone map, we're all going to be looking at slightly different things.
  • Thomas Mansencal: Unless we get all of us to calibrate our displays to the same standard, and have the reference surround. The viewing conditions define the ODT.
  • Joshua Pines: You're also at the mercy of the application you use to view it.
  • Alex Fry: We need diagnostic images or the sRGB/2.2 difference if far greater than our tone scale adjustments.
  • Thomas Mansencal: Some who say it's too contrasty may just be viewing it wrong. Can we make a chip system to assess displays without colorimeters?
  • Alex Fry: I've been using camera phones to assess surround, where the monitor is a known constant.
  • Kevin Wheatley: The BBC did surveys using phone light meters.
  • Jean-Michel Gilbert: ICC profiles seem to be broken in Windows 10.
  • Joshua Pines: Not just in Windows 10.
  • Thomas Mansencal: Limiting participation to people with hardware calibrated displays would be limiting.