Join Lee Lanier for an in-depth discussion in this video Creating a particle beam, part of VFX Techniques: Creating a Laser Battle.
- We have divided our footage, so that we have two shots in two different compositions. Now before I start adding effects to these, I'm going to lay some basic ground work. What I'll do is create a number of different particle simulations, using the built-in effects inside after effects, to create the basic building blocks of more complex things. Now the end goal is to create some futuristic laser beams, that are coming out of these high-tech weapons. Now, instead of rushing straight to, say, shot one, and trying to couple together something there, I'm going to create some separate composition with these particle simulations as a start and built upon that.
Let's try the first one. I'll go to composition, new composition. I'm going call this first one ParticleBeam, so it'll be the core of the main laser beam for our first character. I'm going to keep 24 frames per second. However for the duration, I'm going to increase this to 75 frames. So, I have plenty to work with. So particles have a chance to be born and travel and so on. Now for the size, I'm not going to go with the standard resolution. I'm going to make something that's extra wide so I can have a very long simulation where particles are streaking left to right.
So here I can turn off the lock aspect ratio, and enter my own width. Here I'm going to enter 3840, so it's extra long. Then click okay. I'm going to drag this new new composition into the particles folder, so I know where it is. Then, I'll get started working on it, and see how long that is. Now, when you create particle effects inside after effects, typically when you use the built-in tools, what you do is you apply the effect to a layer, that layer goes away, and you're just left with the particles.
So because of that, I can just simply use a solid layer. I'm going to create a new layer here in this composition, make sure that's selected first layer, new, solid. Initially, I'll make it the same size as the composition. I can just click the make comp size, and I'm not worried about the color right now. The color will go away anyway, and I'll click okay. So, let's apply a particle effect. Now, there's several different ones that come with after effects. I'm going to use a basic one called particle world.
With this layer selected, or this solid selected, I'll go to effect, simulation, particle world. What it does is it creates an icon that the producer or the igniter, and shows you a 3D grid to show you where the particles are. The goal here is to create a simulation where particles are streaking very fast from left to right. (You) can image that'll eventually into a beam. Let's change some of these various properties here. Now actually before I do that though, I think what I'll do is overhang this layer.
Right now it's the same size. I want the particles to be born outside the frame, and then come into the frame fully formed. What I can do is simply scale up this layer or this solid. I'm going to go to transform and scale this up to 150 percent. You can see it overhangs based on the bounding blocks. You can see the particles are ready, in fact, let's just play it back now, so we can see the default simulation. With default settings, it simply creates a shower of sparks that drop towards the floor or the ground through the gravity.
Let's change some of these properties though to make it more left to right streak. The first thing I'll do is change the birth rate from two to a very high number 2000. I want many more particles, that's per second. I'm mostly going to make the particles die sooner, so I'm going to change the longevity from one second to around half, about .45. Now in terms of where the producer is you can actually change that. It doesn't have to be in the center. I'm going to slide mine over to the left so it's over here out of frame.
It's roughly about negative .45. There it is over here. You can also change the radius. The radius is the size of that sphere, and that's the area where the particles are born. I want them to be born over the entire height of this frame. I'm going to change radius Y to a really large number 10. You can see the producer is stretched out. Now in terms of the basic motion, you can change it also. If you go to physics, you can see that the animation is set to explosive.
That makes that explosive shower sparks. I really wanted direction to them, so I'm going to change this to direction axis. Now in terms of what that direction is, you can change that down here under direction axis. In fact, what's going to work for us in this case is zero, negative one, zero, so that's fine. Now, in terms of things like this speed, I can change that. The velocity, I can change to two to make it twice as fast. I can also turn gravity to zero, so they never fall. Now as for this style of particle, you can change that too underneath particle, and defaults on line.
I like to have something a little bit more three-dimensional. I'm going to change this to motion square. It's a simple square, but that is blurred over time. I'll also change the birth size and death size. I'm going to make my particles smaller, so .05. The particles consistent, I'll change both birth and death to .05. I'm going to remove the variation by changing that to zero, so they're consistent. Also, let them be more (opac) with a max opacity of 100. Let's play it back and see what's going on.
So, there's some nice left to right streaky, fast particles. Now, the particles do change in color over time. To avoid that though, I'm going to change the death color, so it's the same as the birth color. I'll just use this eye dropper here to sample birth. Now, the particles are consistent. There's our basic simulation. Just with a few changes to properties, you can get a very different result. Now, there's one last thing I'd like to do here, and that's soften these. Right now, the edges of the particles are pretty hard.
If I apply a blurred to that, I can soften it. I'll go to effect, blur and sharpen, and this time I'll select a directional blur. Increase this to a very large blur length like 100 and get a long streak. Now, I don't really want them to blur up and down, I want them to blur left to right. I'm going to change the direction to roughly negative 90, let's say negative 85. Very close. That gives it a little bit of thickness, but they're definitely blurred.
Let's play that back. There we go. Using the built-in particle effect with some basic creaks to the properties, you can get a very interesting simulation. Again, this'll become the building block of a laser blast. We simply have to add additional effects to it, and then eventually combine it with the main composition.
- Running particle simulations to create beams and sparks
- Altering the beams with distortion, blur, and color effects
- Creating interactive lighting through masking and color grading
- Creating set damage by rotoscoping and integrating matte paintings
- Animating post camera moves
- Matching effects through multiple shots