In PBRT-V3, the light has following spectrum in scene file(Note that the scene file is not come from PBRT itself):

"spectrum" [400.0 0.0 500.0 8.0 600.0 15.6 700.0 18.4]

then it's converted to following RGB in C++:

"rgb" [20.7467213 10.8233843 2.76458955]

is this correct? Why the RGB value exceeds 1? Whether this is used to indicate light intensity?

  • $\begingroup$ HDR lights or as you said it's basically color*intensity in a single rgb triple I guess $\endgroup$ Commented Aug 10, 2021 at 4:43
  • $\begingroup$ Color does not really jave a upper limit. What you see on screen is normalized for the screen device. But that does not mean a blue, brighter more intense blue does not exist. Just not what your monitor can show. $\endgroup$
    – joojaa
    Commented Aug 10, 2021 at 12:55


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