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Continue to ChatQuery : How do I know how dark a color will print in black and white? I've recently been looking into how to obtain a measure of a colour's perceived brightness, for similar reasons, although https://vmapp.org/query/24478/How-Do-I-Know-How-Dark-A-Color-Will-Print-In-Black-And-White-I-Ve-Recently-Been-Looking-Into-How-To-Obtain-A-Measure-Of-A-Colour-S-Perceived-Brightness-For-Similar-Reasons-Although/