When you use a brush in Photoshop and you want to reduce its effect, there are two main settings you can use (you could also adjust the gray, but that’s another tip): You can lower the Flow or lower the Opacity in the Options Bar. This enables you to build up your color in multiple passes and thus get better blending of brushstrokes. So, which one do you use? The short answer is that, for most things, use Flow, which adjusts how fast the “paint” comes out, and this allows you to get smoother blending. The exception is when you’re looking for a consistent tone. Flow is relative, whereas Opacity is absolute. What that means is, if you don’t lift your brush while painting, Opacity will apply everything at the same amount. If you use Flow, it will spill out more paint the longer you hold the brush down. If you’re using pen pressure, Opacity will build up as you move the brush, but won’t pass the set amount if you don’t lift your pen.
This tip originally published in Colin Smith’s “Photoshop Tips” column in the January, 2023 issue of Photoshop User magazine.