Photoshop CIELAB values

Question

So I'm just starting to experiment with Photoshop's Lab channel for colorimetric research, but the values seem to be different from the standard numbers of the CIELAB color space. For instance, the L channel is supposed to have a range from 0-100, while the a* and b* channels have values from -110 to 110, yet when I do a pixel selection, all the values given in the histogram are almost always higher than that. For example, I tested the color values of a yellow dye, and it gave me L = 145.06, a* = 115.90, b* = 171.88, which are out of range. Am I doing something wrong? Or is there a way to convert the above values to something that will fit the color space gamut?

Thanks

Test Screen Name · Answer

In an 8 bit file, in every colour space, the numbers are actually represented as integers from 0 to 255. These are mapped to the actual values you see by the user interface. My guess is that the histogram function only reports these raw numbers, and doesn't map them.

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