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Simple Understanding of Real-World Lighting Values

Discussion in 'High Definition Render Pipeline' started by Phenomonaut, May 18, 2020.

  1. Phenomonaut

    Phenomonaut

    Joined:
    Sep 30, 2012
    Posts:
    61
    If I set the directional light "sun" in my scene to 128,000 lux, which is a real-world value of the sun, then I have to crank an interior point light source to 100,000,000 lumens to light up a room, when that light in real-world terms should only need to be 1,000 lumens. What am I not understanding here?





     
    Last edited: May 18, 2020
    Phenomonaut, May 18, 2020
    #1

  2. SebLazyWizard

    SebLazyWizard

    Joined:
    Jun 15, 2018
    Posts:
    234
    The ambient light (mostly from the sky) is several times more intense than your interior light, so you can barely see it.
    And since there's no global illumination going on in your scene, the ambient light uniformly illuminates everything.
    GI is essential for indoor rendering, atm your room is just as bright as it is outside.
     
    Last edited: May 19, 2020
    SebLazyWizard, May 19, 2020
    #2

  3. SebLagarde

    SebLagarde

    Unity Technologies

    Joined:
    Dec 30, 2015
    Posts:
    934
    Physical light unit and interiror/exterior light have always been challenging, even in real world. When you want to have both at the same time, you need to tweak your value, sadly no choice. Here you must lower the range of your sun, which movie industry do with puting darkening gel on windows usually.

    I recommend this talk for this issue: https://www.gdcvault.com/play/1023284/Lighting-the-City-of-Glass
     
    SebLagarde, May 19, 2020
    #3
    keeponshading and Phenomonaut like this.

  4. DotTeam

    DotTeam

    Joined:
    Feb 12, 2016
    Posts:
    196
    Let me thank you please, as the link provided is top-notch!
     
    DotTeam, Dec 24, 2020
    #4