If you use Photoshop (version 7 and CS), whether it is to paint textures for your 3D-models or for classical digital art, a really good tool is to build your own custom brushes. A custom brush can add that special texture or help speed up your workflow.
You can, for example, use a combination of custom brushes to quickly add cracks, dirt and scratches to textures or images. A digital colorist might need them to paint a underlying texture (skin, cloth, leather, metal) to a section of the painting.
This tutorial will take you through the design of two very basic but effective brushes, and hopefully give you a good idea of how to make your own designs. I will not write about all the settings available, only the ones used for the first brush. A tip though is to use Photoshops help to learn more about the settings, or just go by trial-and-error (the fun way to do it).
How does a brush work?
There's always good to know some of the basics. A brush consists of a basic shape, repeated along the brush stroke to simulate a line. In a basic brush, the shape is a filled circle, with hard edges or soft, blurred edges. The custom settings can use that shape to design many different brushes. Among the examples I have here, we will first take a good look at the "Rough line" brush and then I will give you my settings for one of my favourites, the "Soft dirt" brush.
"The Rough Line"
1. The Brush Tip Shape
First of, we will set the basic size and form of the shape. Since the actual shape is saved as a pixel image, you should design the brush for the size most commonly used. You can make it smaller or larger, but that will change the quality of the stroke. In this tutorial we will build a basic shape, but in some brushes like the "Soft Dirt" below, you will have to use an already existing brush with a completely different basic shape.
Diameter - I will be using this brush for tiny cracks
and for hand-sketched designs, so a low pixel
dimension will be fine.
Angle and Roundness - These are basic settings for the form of the brush shape. I will keep them at default for this brush.
Hardness - Here I adjust the edge of the brush, making it blurred or sharp. I will need some blurry edges later on for the additional effects, so the lowest value will be good.
Spacing - I now set how much space the brush will have between each brush shape. If spacing is checked the shapes will be distributed evenly using the spacing value. By not checking spacing at all, the brush shapes will be distributed in time intervals, with the effect that a slow movement will generate a compact line and a faster movement will create a dynamic dotted line.
It's now time to get the basic roughness into the line. By changing values for how the shapes will follow the brush stroke, we can make the stroke uneven. (Think of it as a simple "noise" effect.)
Scatter - I have a fairly low scatter setting, since I still want the stroke to look like a line (not a jitter of particles). You can decide if the spread should be only along one axis, out from the line center or in both directions (also scattering along the line).
Count and Count Jitter - Since I now have a nice scattering effect along the line, it's time to decide how many shapes I want to use and how much "noise" effect I want. For this brush I will need a low count (don't want too many particles) but I want the actual shapes to mix good. (The scatter setting will keep them in place along the line anyway.)
3. Dual Brush
We now have a nice and rough line. It's a little thick, but that will change a little now. When you create a custom brush, you can add another brush type and use Photoshops layer effects to blend the two. This opens up many variations since you can mix your old custom brushes with your new ones for extra "flavour".
Settings - The settings here are a mix of our two earlier stages, allowing you to design a brush tip shape and customize a scatter for it. I want a fairly basic brush, similar to the one I'm building. Will that have any effect? Yes it will, because here, the magic comes from the "Mode" setting. I choose to let the new brush burn away the edges of the custom brush, giving me a thinner line with an additional smudge quality to the roughness.
4. Other Dynamics
So far, we have a rough but very black and compact line. Since this brush will be used for rough sketching, I want a good opacity blend within the line (also with a noise quality).
Settings - Here we can use the settings to make the brush shapes vary in opacity when they are distributed. both of the controls have similar effect, but not quite. They both control different values in a Photoshop brush (look at the settings for a brush, you have an opacity control and a flow control, both with percent values). You can also control if the jitter should be pressure sensitive, or if you might want a "fade" effect (makes the line fade away after a certain stroke length). I will keep both control values off for this brush.
Now we're almost done. All the basic settings we need for this brush are done, but adding a few more qualities to it will make it even better.
5. Extra Settings
There are a couple of checkboxes that can add special qualities to a brush. For this brush we will check "Airbrush" and "Smoothing".
Airbrush - If a brush have a the airbrush quality it will keep adding colour if you paint in the same place or keep the brush still (but the mouse button pressed).
Smoothing - This setting will use up a little more memory but will keep corners or curves smooth when you paint them fast (good if you like hurried painting using a stylus).
6. Shape Dynamics
This is an additional setting you should consider if you use a stylus or if you like using "stroke path" set to "simulate pressure". There are many settings here that we could use to change the basic brush shape more, but for this tutorial I will only use one setting. Set the control to "Pen Pressure", and the line will get fine, fading stroke-ends.
7. Save it!
Don't shut down your computer just yet. Now you have to add the brush to your brush library. Press the triangle (brush tab - top right corner) and choose "New Brush Preset..." or "New Brush..." (depending on which version of Photoshop you are using). This will allow you to name the brush, and it will be added to your ordinary brush library.
You now have a good all-round brush that you can start painting with.
Hope this tutorial gave you some help with custom brushes and now it's up to you to try and build your own brushes.
Now, as a treat, I will also give you the settings for my "Soft Dirt" (Below)brush.
"The Soft Dirt"