CHROMiX

Why is the gamut of flatbed scanner profiles so wide?

It’s inconvenient because I can not attach screeen captures but you can easily compare those. Anyway, flatbed scanner profiles generated using IT8 targets show enormous gamut, looking a little weird. Digital camera profiles generated using GretagMacbeth ColorChecker SG are smaller in gamut, looking pretty normal.
I suppose the scanner profile gamut is obviously affected by the IT8 reference target values, but as you know the gamut represented by the IT8 target patches’ Lab values is quite small. Then what makes the scanner profiles so large in gamut? What exactly defines the gamut of scanner profiles? Any explanations?

I’ll hazard a guess here. If your talking about a scanner profile generated from a transparency, then you’ve got the scanner emitting light. The camera profile is probably of a reflective target.

If you’re talking about a scanner profile generated from a reflective target then I guess there’s the intensity of the lamps and their proximity to the target. Isn’t light intensity the inverse of the square of the distance?

Yes I was talking about reflective scanner. When it comes to light intensity, the sunlight used to generate camera profiles would be much much stronger, but camera profiles don’t show that wide gamut. Thanks anyway for your answer. I welcome any thoughts.

I thought this topic sounded familar. Another user was asking about scanner profiling a few weeks ago under the ColorValet topic heading, and I went into our scanner profiling service at some depth.

[one.imports.literateforums.com/t/scanner-profiling-colorvalet/338/1)