How to visualize visible colors in CIE Lab?

[hminle]

Hi Colour Team,

Is there a way to visualize visible colors in CIE Lab?
Like this example: https://en.wikipedia.org/wiki/File:Visible_gamut_within_CIELAB_color_space_D65_whitepoint_mesh.png

Thanks

[KelSolaar]

Hello,

We don't have a direct way to visualise it with Matplotlib but the solid can be built with the colour.volume.solid_RoschMacAdam definition that produces CIE XYZ values that can then be converted to CIE Lab.

We are using it there for example: https://www.colour-science.org:8020/

Note: I think the Axis labels are flipped, I need to do a pass on that!

[KelSolaar]

Sorry, just to clarify, are you talking in 2D or 3D here?

[hminle]

Hi, it's 3D, CIE Lab in 3D

[KelSolaar]

We have limited 3D support in Colour and visualising the Rosch-MacAdam solid is not implemented atm. Given the poor state of MPL with 3D, it might never be.

[hminle]

I got it. Thank you anyway

[hminle]

Hi @KelSolaar , on the above visualization that you posted from https://www.colour-science.org:8020/
Is there any way to make the 3D visible gamut colorful?

[hminle]

Hi @KelSolaar , just curious about the Rosch-MacAdam solid in CIE 1931 XYZ.
If we can visualize all visible colors in CIE XYZ, the values of them can go beyond the range 0-100 in the axis X and Z?
Like this figure

[KelSolaar]

Hey @hminle,

This is a great question, technically, ignoring photoreceptor bleaching and saturation, there is no limit, it is however useful to bound them for practical purposes. Here we use a series of square pulses whose bandwidth grows from 1 wavelengths to the entire set of wavelengths to produce the Equal Energy and Unity Illuminant E. If you assume that E is the maximum possible relative radiance, then this is the limit of the Rosch-MacAdam solid.

Cheers,

Thomas

[hminle]

Thank you, I got it.