I wanted to show you some of the (really easy) possibilities of this tool, so I put together a small tutorial and I'm going to show you a lot of examples of the kinds of shapes and effects that the blend tool is capable of.
The blend tool takes 2 (or more) shapes in Illustrator and essentially ‘morphs' the first shape into the second by creating a number of steps in between the 2. If you blend and then “Edit > Expand,” you get paths for all of the shapes in between.
There are 3 different Ways the Blend tool can blend: Specified Steps, Smooth Color, or Specified Distance. We will take a look at all 3 with some simple examples.
1. Blending using “Specified Steps”
The first example is probably the most requested, Abstract lines. I don't want to steal N.Design Studio's thunder so here is a link to their tutorial on abstract Backgrounds. It's easy to do and you'll see an example below of a shape made by following that tutorial.
2 lines blended with 15 steps, .25pt stroke:
4 lines blended with 15 steps, .25pt stroke:
Once I read that tutorial, I started playing around more with the blend tool on different kinds of shapes. The first few examples will be using the Specified Steps mode of the blend tool. To set the mode, go to Object > Blend > Blend Options, and in the drop down menu select “Specified Steps.” Set a number of steps to be used, and click OK. (I will be using 15 steps for all of the examples shown here, including the abstract lines above.)
Now that you have your Blend options set to Specified Steps, (Note: You can also set the Blend Options by double-clicking on the Blend Tool in the Tool Palette) make 2 simple shapes on your artboard. I used a Circle and a Star.
Now you can blend it 2 ways: Go to Object > Blend > Make, or key Command+Option+B (Mac) or Control+Alt+B (PC). You can also use the actual tool from the palette, but I like just selecting BOTH shapes and hitting the keyboard shortcut. Make sure you have the shape you want on top On Top. (this will affect your blend more noticeably when using fills instead of strokes) Here is the result, 15 Steps, 1pt stroke on both shapes:
You might notice that even after the Blend, you still only have 2 paths. In order to get paths for all of the steps in between, go to Object > Expand.
You'll get a prompt for what you want to expand to. I usually just hit ok with the default (all). Note: Expanding your blends goes for the rest of the examples in this tutorial. You can achieve different results by changing the number of steps and stroke size. The shape in the exact middle will change and other shapes will have no effect. Here, the results change drastically and even a slight change can have a massive effect on your work. By practicing to change different customizations, you can easily examine the way the whole shape changes in proportion to the different settings. Blending refers to mixing up similar things in a smooth manner so that they appear to be nice and clean.
Here is what the paths look like “expanded.”
Here I made the star the bigger shape and used the same blend settings. (15 steps, 1pt stroke on both shapes)
Ok, remember we are still in the Specified Steps part of this tutorial, and now we are going to play with a few more details. I used the same star and circle from above and made the stroke on the circle 3pt. instead of 1 pt. These are small details, but you can get striking results:
15 steps, with different colors and stroke sizes:
15 steps, with different fill colors: (the circle is on top)
15 steps, with an artistic brush stroke, applied:
You can also select your paths with the Direct Select Tool (White Arrow) AFTER you apply the Blend and make changes. I don't recommend doing this if you have an extremely complex blend. It could bog you down. All I did here was move the circle path around after the blend was applied:
Now, I made the 2 shapes overlap before I blended, like this:
15 steps, with different stroke sizes:
15 Steps with different Stroke sizes and Stroke colors:
2. Blending using “Smooth-Color”
I don't use this option quite as much because it is really apparent as to which shape is on top, and it seems to be pretty limited for me as far as uses go, but I'll show you how it works.
There is no setting for steps in with this option because smooth color assumes you want to ‘morph' the color, AKA a gradient blend. As an example, I used 4 stars shown below. The smallest being on the bottom, and the large blue star on top.
Make sure to change your Blend Options to “Smooth-Color” if you are following along. Here is what the smooth color blend of the 4 stars looks like:
As I said, this option is pretty limited (in my opinion) because of the depth factor, but I have found a hidden gem in my experimenting! Once you have your smooth color blend, if you “Expand” (Object > Expand) the shape, you get an intricate set of paths that represent the steps in between. Then all I did was get rid of the fills and put a .25pt stroke on them. It's kind of like a 3d wireframe. Check out the result:
3. Blending using “Specified Distance”
This option is pretty much a mix of the 2 above. Instead of specified steps, here you set a specific distance between the “steps” in the Blend. This has it's advantages because you don't have to worry about having too many steps and getting a solid color (unless you go with a smaller distance than your stroke size). Say you set your distance to 15 pixels. . . Illustrator will make a step every 15 pixels, no matter how far apart your 2 shapes are. So it is a good way to control the gaps between the steps.
Again I used a star and a circle. like this:
Blended with 7px distance, both 1pt strokes, different stroke colors:
Blended with 12px distance, both 1pt strokes, different stroke colors:
Blended with 12px distance, different stroke sizes, different stroke colors:
Here, I moved the circle outside of the star and still used a 12px distance, but different stroke sizes and colors:
Same as above, but with an artistic brush stroke (oversized, like 10pt):
These are VERY SIMPLE examples. You can easily take this tool and get very complex, very quickly. (and not as symmetrical as in my examples) I hope you have fun with the blend tool as I have been. I use it more and more each day, and the more you try it, the better you get at predicting it's results.