Halftones were originally a technical solution for printers to represent gray scale images using a single color ink, by varying the size of points in a fixed pattern to give the appearance of lighter or darker areas. However, scaled up this sort of raster effect can also be used to create interesting designs regardless of format. Since it’s difficult to do manually this sort of effect is also a good use case for a parametric design tool like Paragraphic where you can automate the process and easily tweak settings non-destructively.
If you’re on macOS and want to work with custom vector halftones you should also check out our specialized halftone design application Vectoraster. But here we’ll continue with working with halftones in Paragraphic.
This video gives you an introduction to working with halftones in Paragraphic along with some examples, or you can read about this more in depth below.
Source and pattern layers
In Paragraphic, like many other illustration tools, each document is separated into layers. Each thing you add into the document becomes a layer and you can edit and move the layers independently.
In order to create a halftone effect we need two layers to start with. The first will be our “source layer”, this will be the layer with the content we base the halftone effect on. For example an image you want to reproduce as a halftone dot raster pattern. In the example below we use an old portrait photo of Darwin. You can see that it’s very low resolution, which isn’t a problem. For creating nice halftone effects you typically just need images 200-300 px wide.
The second layer we need is the actual halftone pattern. For this layer we start out adding a simple shape that will be our point shape, like a circle, a square, line or any other shape. And then we use the area repeater tool to create a grid repetition of this shape.
We’ve hidden the image source layer for now to make it easier to see what we’re doing with the halftone pattern. As the process is non-destructive you can easily adjust point shape, size or pattern spacing at any time to change the effect appearance.
The Apply layer node
Once you have your source layer and a pattern in place the next step is to use the Apply layer node to create the actual halftone effect. You can add this as the next step on the pattern layer using the Add node button and selecting the Group: Apply layer node.
This node uses the content of one layer (the source layers) to apply effects to the individual elements in another layer. Like for example using the light level in a source layer image to scale points in a raster pattern to create a halftone.
The first thing we then need to do in this apply layer node for it to work is to set what layer it should use as the source layer. To do this simple click and drag from the input socket for the source layer and drag a connection to the image source layer. Once this is connected we can now see that the points in the pattern are scaled based on the image in the source layer.
You can now continue to adjust the pattern or point shapes and see the effect update with each change. By default the Apply layer node applies the change as uniform scale, but you can also experiment with having it apply other changes, like changing the color or rotation of the points.
You can also try offsetting or rotating the entire pattern layer or the source image layer to adjust the appearance of your effect.
Conclusions and combinations
We’ve now made a basic halftone effect, but this is just the starting point of what you can do with halftones in Paragraphic. As the pattern layer works like any other in Paragraphic you can freely use any other nodes in Paragraphic to for example add randomization to the pattern or some other transformations to the points. You can also combine multiple layers with different settings to create interesting effects. For some examples of this you can take a look at the video linked at the top of this post.
