what is gretamackbeth colorcheker
 

What is it exactly? as far as i have seen is a color card with i suppose a software to identify each color. But is it compatible with any edition software? is it easy to use? and the price?

Gretag-Macbeth ColorChecker
 

The original Macbeth color chart with 24 colored squares has been around for a long time, at least 30 years. It was intended for use as a standard color reference to permit photographic prints to have accurate color (basically, you fiddle with your development process until the printed image corresponds closely to the original color chart.) You can use it other ways; I have used it to compare video cameras, see for example http://www.bealecorner.com/gl1/color/mac790.jpg

The company is now called GretagMacbeth and they have various products including a more complicated "ColorChecker DC" chart for digital cameras which may have software associated with it for color calibration of monitors or printers; I'm not sure- you can check their webpage at
http://www.gretagmacbeth.com/Source/Gm.asp