Hi, I love ColorPick , but I'm kind of confused regarding the Hue-Saturation-Lightness model. I'm new to technical color theory, but I thought the Light parameter should be Value or Brightness the way it's being used in ColorPick. In the HSL model the Lightness goes from pure black (0) to pure white (1), whereas in HSV/HSB, the V/B goes from zero light to maximum light.

Thanks for the question. In the ColorPic the Lightness goes from 0 to 100, and the conversion factor used is the HSV model, so the label should really read 'Value' or 'Brightness' and not 'Lightness'. This is something that we will change the next version so it's less confusing.

ColorPic uses an algorithm similar to Photoshop's HSB (Hue, Saturation and Brightness) values, although I believe that the numbers are rounded slightly differently so you may see very minor differences when copying values between the applications.

There is some confusion about color spaces and the various different terms used. I defer to the following write-up from wikipedia: http://en.wikipedia.org/w...olor_space

From this we can take the HSB and HSV terms to mean the same thing, the brightness or value component being the maximum value of the red, green and blue components. HSL computes the lightness by summing the average of each of the R,B and B components.

There are still more color spaces and confusion reigns about the exact meanings of each of them. Apart from the two major HSV and HSL color spaces the third component can also be calculated perceptually based on color weighting as follows:
(76 * R + 150 * G + 28 * B) / 255

This follows the theory that a pure green is brighter than a pure red or blue.

I hope this hasn't confused you further.

If you'd like to take a look at version 4 of the ColorPic you;ll see that we've made some major improvements and moved over to the HSV model.

you could check this article to have a detail information about the two different color spaces
http://www.acasystems.com...-color.htm