The pickup well is one that has paint flowing into it and continuously mixes the colors of where you paint with the color that’s contained in the reservoir well. This is the color you see displayed in the Load preview swatch. The reservoir well color is defined by the current foreground color swatch in the tools panel or by Option/Alt-clicking in the image canvas area.

The mixer brush tool has two wells: a reservoir and a pickup. In the meantime, let’s take a look at the Options bar settings for the mixer brush that’s shown below in Figure 1. Fortunately, the Tool Presets panel can help here and the easiest way to get started is to select one or two of the new brush presets and experiment painting with these brush settings to gain a better understanding of what the new brush settings can do. It’s not particularly easy to pick up a brush and play with it unless you have studied all these brush options in detail and can understand how the user interface is meant to work. The brush controls are split between the Brush panel, the Brush Presets panel, the Options bar and the new Bristle preview. The only downside is that the user interface has had to become even more complicated. The combination of the mixer brush and bristle tip brushes provide a whole new level of sophistication to the Photoshop paint engine. The mixer brush can be used with the new bristle tips or with the traditional Photoshop brush tips (now referred to as static tips) to produce natural-looking paint strokes. With the mixer brush you can mix colors together as you paint, picking up color samples from the image you are painting on and set the rate at which the brush picks up paint from the canvas and the rate at which the paint dries out.

The mixer brush tool allows you to paint more realistically in Photoshop.

How to make brush strokes in photoshop