The Sponge tool, which is located in the group with the burn tool and the dodge tool, is used to increase or decrease the colour saturation.

 

 

When you increase colour saturation, you are increasing the brightness and strength (intensity) of a colour to make it more vivid. Desaturating is the process of making a colour less vivid (duller or less intense).

 

To use the Sponge tool, first select it from the toolbox and then adjust its options in the options bar.

 

 

In addition to the standard brush options, you will see two additional options called Mode and Flow. From the mode drop list you can select either Desaturate, which will make the colour less vivid by drag your mouse over the image, or saturate, which will make your colour more vivid when you drag.

 

You can use the Flow slider switch to control the strength of the sponge tool’s effect. Higher values strengthen the effect, and lower values weaken it. To begin, use a lower flow setting. Remember, you can always repeat your strokes to make a stronger effect as an alternative to increasing the flow value.

 

As with the burn and dodge tools, use small brush sizes for detailed work, and larger brush sizes for large evenly blended areas.

 

Do not confuse the results from the Desaturate setting for the sponge tool with the results produced by the dodge tool. The sponge tool desaturates colour, that is, it makes the colour less pure or intense. The dodge tool affects the lightness of the colour.

 

After you select the sponge tool and set up its options, you can create your desired effect by dragging your mouse pointer over the specific region of the image that you want to saturate or desaturate, as the case may be. It is probably best to start with a lower flow value until you become accustomed to using the sponge tool.

 

In the images that follow, the eagle on the left has had its beak saturated with the sponge tool. The brush size used was 17 pixels and the flow was set at 17%.