Octane’s lights differ from the majority of R’G’B’ renderers who are using the very standard intensity and exposure parameters “combined” via the math-formula for the “total light emission value” (simply said). Spectral light transport model versus a given R’G’B’ rendererĭisclaimer: I do not like doing A|B “versus” or “comparison”, in the sense that most of the time, on social and video platforms, they are being produced fallaciously - many often, evaluated based on a perceptual difference, without ensuring technical correctness.įor this comparison below, I wanted to keep it simple, using the same base-line but as I am using two different offline-renderers, the scene has some dissimilarities.įor time constraint reasons and because it is rather inessential, the lighting is not perfectly matched and as mentioned, it is inessential for this test. Many R’G’B’ renderers are that way: they support a few “spectra-features” that do not define them as spectral-renderer as they do not adopt a spectral light transportation model.
An other spectra-feature example is kelvin temperature for light-blackbody-radiation and/or emission shaders, for instance.
The pseudo-spectral renderer which is, at its core, an “RGB renderer” but with a few spectra-features.Ī well-known spectra-feature is “glass-dispersion” such as how it has been implemented in LuxCore (which makes LuxCore, currently, not a true spectral renderer). In very short and simply explained, It calculates spectrally and shows a preview on your monitor via an output device transform (by default, Linear-sRGB to sRGB display referred) “just for preview purposes” and so, maintains all the linear-scene-referred and high dynamic range data when rendering and exporting to OpenEXR | Suggested reading: CGI: Color Management 101 (“Survival Kit”).
The spectral-renderer that still converts to an RGB color space model outside of the spectral domain and in particular to the “sRGB” color space (BT.709 chromaticity primaries coordinates, sRGB EOTF and, assuming, a CIE Standard Illuminant E Series aka “white point”).