The YRGBK droplet – Color separating with the Lab mode

The YRGBK droplet is a color separation script for Adobe Photoshop which generates a set of printable, complimentary colors from an RGB document. I use this script to begin the separation process.
Get it here.

Base color generator
A finished image can be processed through the YRGBK script to create a  set of standard colors for color separation work. The resulting channels can be used to build a simulated process color separation, or used as a base for spot color separation. By starting with a base set of standard colors, I can be sure all the color data is included in the separation. Depending on the image, some color channels will contain little or no pixels and can be discarded, while additional spot color channels can be added to customize a color separation.

munsell_Lab

A standardized approach
The YRGBK script provides a standardized approach to generating simulated process and spot color channels. The colors are pulled directly from the hue values in the Lab mode. The concept is simple and is based on the separation of color into Hue, Saturation and Value.

The Value in an image is handled by the L channel in the Lab mode, which is converted into printable Black and Gray channels. The remaining color channels are broken into 7 separate Hues; Yellow, Red, Green, and Blue, plus Cyan, Magenta and Purple. The Saturation is determined by the density of each channel.

This color wheel shows how the base colors and the Luminosity can be combined to make a 3 dimensional color sphere. Any color within this sphere can be represented with the combined channels.