Chapter 11: Using a Brush Mask
The Brush can be used in either Paint mode or Erase mode to add to or subtract from areas of the mask. Clicking on the Paint option will add white areas to the mask. These areas will be preserved on the current layer. Brushing with Erase mode is handy for “trimming” overspray of the mask and making your selection more accurate.
To control a brush, click the Brush Settings drop-down menu (it’s next to the Erase option). In this window, you can configure all the paint brush settings such as Size, Opacity and Softness. In the center of the grid there are various presets for quick selection.
If you have a pen tablet attached, you can also configure Pen Pressure, which effects Radius and Opacity levels.
Here’s how to use the Masking Brush tool.
Click the Add Layer button (+ symbol) or choose Layers > Add New Adjustment Layer. Let’s add an obvious effect so it's easy to view.
With the adjustment layer selected, click the Add Filters button.
Apply the Dramatic effect and increase the sliders to a high setting.
Create a Layer mask on the adjustment layer by clicking the Edit Mask button.
Choose Brush from the pop-up list. You now have two options to decide how the initial mask is created.
Paint. Clicking with the Paint tool allows you to paint the effect onto the image.
Erase. Clicking with the Erase tool allows you to remove areas of the effect from the image.
Click the Visibility icon (eyeball) to view the Mask.
Continue painting the mask to get the desired results. Use the toolbar at the top of the window to control the behavior of the Masking Brush tool. Click the Brush Settings drop-down menu to control the shape and dynamics of the brush. You can also click on each property in the top toolbar to edit them individually
Size. Controls the diameter of the brush. You can also use the keyboard shortcuts [ and ] to make the brush smaller or larger.
Softness. Controls how much blending there is between the center of the brush and its edges. This can create a more gradual blend on any mask. You can also use the keyboard shortcuts of Shift + [ or ] to make the brush harder or softer.
Opacity. This controls the overall opacity in the brush. A brush at 100% has full impact. A brush set to 50% will only add or subtract half of its strength.
Pen Pressure. If you have a pen tablet attached, you can also configure Pen Pressure, Radius and Opacity levels. This allows you to draw on the tablet and have the force applied to the pen transfer to the size and density of the brush.
Click and paint on the canvas to modify the selected mask (layer or adjustment layer).
To refine the mask even more, click the Mask Menu to modify the Density and Feathering for the mask. This can control how the mask applies and help blend its results more.
Density. Controls the transparency of pixels outside of a mask so the overall the mask fades into the background better.
Feather. Blurs the edges of a mask to more naturally fade the mask adjustments into the image.
Toggle the mask visibility off by clicking the Visibility icon (eyeball) in the toolbar.
When satisfied with the mask, click the Done button in the toolbar.
