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• Convert spectral distribution to RGB color

• Is it possible to insert new colour schemes into ColorData?

• Convert spectral distribution to RGB color

• Is it possible to insert new colour schemes into ColorData?

cf. "VisibleSpectrum" similarly over gray blended in XYZColor and RGBColor respectively:

Note that neither rendering of this spectrum has the vibrancy of newVisibleSpectrum.

Notice:

Simon Woods did just this months ago for an answer I missed:

• Convert spectral distribution to RGB color

It seems that it can. By spelunking ChromaticityPlot I found:

Image`ColorOperationsDump`$wavelengths Image`ColorOperationsDump`tris 

These are a list of wavelengths and their corresponding XYZ color values used by this plot command:

ChromaticityPlot["sRGB", Appearance -> {"VisibleSpectrum", "Wavelengths" -> True}] 

We can therefore use them to generate a new color function:

ChromaticityPlot; (* pre-load internals *) newVisibleSpectrum = With[ {colors = {Image`ColorOperationsDump`$wavelengths, XYZColor @@@ Image`ColorOperationsDump`tris}\[Transpose]}, Blend[colors, #] & ]; 

A comparison with the old function:

ArrayPlot[ {Range[385, 745]}, ImageSize -> 400, AspectRatio -> 0.1, ColorFunctionScaling -> False, ColorFunction -> # ] & /@ {"VisibleSpectrum", newVisibleSpectrum} // Column 

589nm is now the bright sodium yellow that it should be:

Graphics[{newVisibleSpectrum @ 589, Disk[]}] 

If you wish to integrate this into ColorData see:

• Is it possible to insert new colour schemes into ColorData?

As requested by J.M. red-green-blue plots for each function:

old = List @@@ Array[ColorData["VisibleSpectrum"], 361, 385]; new = List @@@ ColorConvert[Array[newVisibleSpectrum, 361, 385], "RGB"]; ListLinePlot[Transpose @ #, PlotStyle -> {Red, Green, Blue}, DataRange -> {385, 745} ] & /@ {old, new} 

Clipping occurs during conversion to screen RGB; the newVisibleSpectrum function actually produces unclipped XYZColor data. For example projected over gray:

newVSgray = With[{colors = Array[{#, Blend[{newVisibleSpectrum@#, ColorConvert[GrayLevel[2/3], "XYZ"]}, 0.715]} &, 361, 385]}, Blend[colors, #] &]; ListLinePlot[ List @@@ ColorConvert[Array[newVSgray, 361, 385], "RGB"] // Transpose, PlotStyle -> {Red, Green, Blue}, DataRange -> {385, 745}, ImageSize -> 400] 

Which corresponds to the plot:

ArrayPlot[{Range[385, 745]}, ImageSize -> 400, AspectRatio -> 0.1, ColorFunctionScaling -> False, ColorFunction -> newVSgray, Background -> GrayLevel[0.5726]] 

Notice:

Simon Woods did just this months ago for an answer I missed:

• Convert spectral distribution to RGB color

It seems that it can. By spelunking ChromaticityPlot I found:

Image`ColorOperationsDump`$wavelengths Image`ColorOperationsDump`tris 

These are a list of wavelengths and their corresponding XYZ color values used by this plot command:

ChromaticityPlot["sRGB", Appearance -> {"VisibleSpectrum", "Wavelengths" -> True}] 

We can therefore use them to generate a new color function:

ChromaticityPlot; (* pre-load internals *) newVisibleSpectrum = With[ {colors = {Image`ColorOperationsDump`$wavelengths, XYZColor @@@ Image`ColorOperationsDump`tris}\[Transpose]}, Blend[colors, #] & ]; 

A comparison with the old function:

ArrayPlot[ {Range[385, 745]}, ImageSize -> 400, AspectRatio -> 0.1, ColorFunctionScaling -> False, ColorFunction -> # ] & /@ {"VisibleSpectrum", newVisibleSpectrum} // Column 

589nm is now the bright sodium yellow that it should be:

Graphics[{newVisibleSpectrum @ 589, Disk[]}] 

If you wish to integrate this into ColorData see:

• Is it possible to insert new colour schemes into ColorData?

As requested by J.M. red-green-blue plots for each function:

old = List @@@ Array[ColorData["VisibleSpectrum"], 361, 385]; new = List @@@ ColorConvert[Array[newVisibleSpectrum, 361, 385], "RGB"]; ListLinePlot[Transpose @ #, PlotStyle -> {Red, Green, Blue}, DataRange -> {385, 745} ] & /@ {old, new} 

Clipping occurs during conversion to screen RGB; the newVisibleSpectrum function actually produces unclipped XYZColor data. For example projected over gray:

newVSgray = With[{colors = Array[{#, Blend[{newVisibleSpectrum@#, ColorConvert[GrayLevel[.66], "XYZ"]}, 0.715]} &, 361, 385]}, Blend[colors, #] &]; ListLinePlot[ List @@@ ColorConvert[Array[newVSgray, 361, 385], "RGB"] // Transpose, PlotStyle -> {Red, Green, Blue}, DataRange -> {385, 745}, ImageSize -> 400] 

Which corresponds to the plot:

ArrayPlot[{Range[385, 745]}, ImageSize -> 400, AspectRatio -> 0.1, ColorFunctionScaling -> False, ColorFunction -> newVSgray, Background -> GrayLevel[0.567]]