In the Panel or window set and , and in the window set .
See also Sketch on a Cintiq.
Opacity is a way of representing how “see-through” a brush’s paint is. (Opacity is the opposite of transparency.) You cannot see anything underneath paint that has an opacity of 1. The lower the opacity, the more you can see through the paint. Paint that has an opacity of 0 is perfectly clear and invisible.
See Change the opacity of an image layer.
Most brushes in Alias have two types of opacity: brush opacity (controlled by the and options) and paint opacity (controlled by the option).
The difference between brush opacity and paint opacity becomes noticeable when you paint more than once over the same spot. If the brush opacity is less than 1, the paint will build up and become more opaque. If the paint opacity is less than 1 (and the brush opacity is 1), the paint will not build up.
In addition, you can make the brush opacity change based on how hard you press the stylus on your tablet. The is the minimum opacity for the brush (when you press lightly with the stylus) and the is the maximum opacity for the brush (when you press hard with the stylus). If you do not want the opacity to vary with stylus pressure on the tablet, set the and the to the same value.