How to get a grainy/dithering effect on drawings?

Question

I've been looking at art from an online game called Maplestory and I've noticed that much of the art as well as the in game backgrounds, characters, etc., have this really nice grainy effect and I've been trying to achieve it (using photoshop) but I can't get it to look the same. I've tried using the noise effect but it's not the same. The effect looks more like a dithering effect that pixel artists do, but I'm assuming the artists for these drawings do not place individual pixels, considering the resolution of the drawings, but I don't understand how they are able to achieve this effect.

Here are some examples: (Might need to zoom in to see the effect properly)

Notice how this looks much cleaner than just the noise effect. Also, some areas seem to be grainier than others, which makes me feel like this isn't just some sort of effect they're throwing over it.

Also notice how it looks like the shading was done with this effect. A good place to zoom in on is the grass or the trees

Answer 1

The name of the effect is dithering.

Today we can show millions of colors on the screen at the same time, enabling (seemingly) smooth gradients.

In earlier days the color palette could be restricted to very few colors. On CGA displays for example, you could only show 4 colors on the screen at the same time.

Dithering is a technique of mixing two (or more) colors by applying some kind of pattern, "weaving" the colors together. (It is similar to the way the CMYK colors blend together using screen dots.)

There are different ways to accomplish this.

Originally, dithering was done "by hand". You simply choose a restricted color palette and then manually position each pixel. This is an art form and takes a lot of practice. You could google "pixelart dithering tutorial" to learn more about this.

A quicker way would be taking your original RGB image and change the color mode to indexed color (Image/Mode/Indexed Color). This enables you to reduce the number of different colors in the image.

Take a look at this smooth gradient:

Below I show how it looks if we convert this gradient to two color using Photoshop's 4 different dithering styles:

None:

Diffusion:

Pattern:

Noise:

You should try playing around with the settings. In your case you might want to choose 256 colors to achieve the right "retro" feel, but since we do not have an example of the art you want to apply the effect to, it is hard to tell what would work in your case.

Answer 2

If you really want this kind of effect for shading, you can paint a layer by scatter brush or have a texture. The dots can be black or grey and the space between them must be transparent.

• Insert that layer just above the layer to be shaded
• select blending mode = hard light
• adjust the depth by selecting the opacity less than 100%
• remove the exessive dots by eraser or insert a layer mask. Both methods can produce a gradient if the dots are faded gradually, no need to make the dots gradually sparser like the real dithering does
• do not merge the layer until you are sure!

Variation is possible by selecting non-grey color and playing with blending modes.