Tutorial 159 - Photoshop's Mixer Brush - Reservoir and Pickup (Patreon)

This tutorial explains photoshop's concepts of the reservoir and the pickup well. We only need to keep these concepts in mind when using the mixer brush.

The reservoir 

The reservoir is simply the idea of a container holding the color that has been selected to paint with. When using the normal brush, our active color is displayed in the tools panel as a swatch (the foreground color) but for the mixer brush we need to look at the swatch displayed in the mixer brush options bar (seen only when the mixer brush is selected), and usually sits just above the document window. 

The pickup well 

The pickup well is another concept used by photoshop. We really don't need to think of this as a well at all, it's just color that is picked up by the brush after each stroke. The amount of color that is picked up by the brush can be controlled using the Wet percentage. We can see a small preview of the pickup in the mixer brush swatch, shown in my example as blue. This is an indication of color influence on our next stroke. 

The reservoir supply 

The reservoir supply can be controlled using the Load percentage, which essentially tells the brush how soon to run out of paint. Lower values mean less supply, so the brush, when making a stroke, will run out of paint sooner. At 100% the brush stroke has an infinite supply of paint. 

More about the reservoir 

The reservoir can also be empty, which will be indicated in the swatch with the transparency checker-board. This is similar to a dry brush. The reservoir can also be a stamp, cloned using the eye dropper. The "pickup paint from all layers" button needs to be activated (on the options bar, icon looks like a stack of layers) and we also need to have the "Load solid colors only" option unchecked (found in the drop down menu on the mixer brush swatch.

In the future tutorials we'll see how we can control the ratios of the reservoir and the pickup well using the Mix control as well as exploring ways we can get the mixer brush to mimic  traditional media.