Tolerance measurement

[ilgk48]

Good afternoon to all,
maybe an old question but I do not find an answer.

How Tolerance is measured?
Example: If I wish to substitute with RGB(123,147,201) (casuals numbers ) the color RGB(57,65,124) with a Tolerance of 10, which are the colors similar to RGB(57,65,124) affected?
Maybe +5 and -5 relatively to the Hex code of the color RGB(57,65,124)? ... I do not know.

Thank you.
Paolo

[LeviFiction]

It depends on the tool and the mode. Sorry, but there is definitely not just one way in which tolerance is defined.

Take the Magic Wand tool. RGB mode is indeed just R±Tolerance & G±Tolerance & B±Tolerance. The other modes, have their distinctions and I am uncertain what all goes into the math or how tolerance affects it. Just going by the descriptions of how they select colors for each mode you can probably tell why tolerance works little differently between modes.

• RGB Value — selects pixels that match the red, green, and blue values of the pixel you click
• Color — selects pixels that match the shading variations of the pixel you click
• Brightness — selects pixels that match the perceptual lightness value of the pixel you click
• Perceptual — selects pixels that match the perceptual shading variation and lightness of the pixel you click
• Traditional — selects pixels that match red, green, and blue values, with a bias toward lightness variations. This match mode is therefore more discriminating than the RGB Value match mode.

[ilgk48]

Thank you Levifiction,
sigh!
Anyway very, very useful
Paolo