HSL stands for Hue, Saturation & Lightness and it’s one of the main ways to represent RGB color values. You’ll also often see HSB, for Hue, Saturation & Brightness, which is essentially the same thing. It can be confusing at first to understand what it all means, so here’s a short post to help you make sense of it all. This should help you when it comes time to play with colors in Photoshop and color toning your photos. I can also help with proper use of the different blend modes.

The main advantage of defining colors in terms of hue, saturation and lightness is that it’s often more intuitive than defining a color only in terms of the Red, Green and Blue values. It’s easy to picture how a less saturated version of a color would look like for example.

Hue

The Hue is what we most often think as color. It’s calculated in degrees of the color wheel and it’s refers to a color wheel that goes from red, to yellow, to lime, to aqua, to blue, to magenta, and finally back to red. For this reason, 0° on the hue color wheel is red and then 360° is red again. Hue always refers to the base color.

Hue Value Wheel

Saturation

Saturation is how pure the hue is. A full saturation means that the pure base hue is used. Saturation is calculated as a percentage value between 0% and 100%. 0% saturation will always be black.

Saturation Value

Lightness / Brightness

Lightness (or brightness) is the amount of white or black mixed in with the color. It’s also calculated as a percentage value between 0% and 100%. 0% lightness will also always be black.

Lightness Value

Final Tip: In Photoshop, you’ll be able to see how HSL get calculated. In the main color picker, if you move the color point from left to right, you’ll see that the Saturation value gets updated, then if you move the color point from top to bottom, it’s the Lightness (Brightness) value that gets updated. Finally, if you you select a different base color to the right of the vertical color picker, the hue gets updated.