Join Lee Lanier for an in-depth discussion in this video Creating a streaked particle blast, part of VFX Techniques: Creating Particle Effects.
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We spent some time creating an energy field on the tip of the wand using various particle simulations. We're now ready to move on and create the actual blast the wizard fires off at his enemy. We'll do that with another particle simulation, but we'll make it look much different. Instead of a sphere or a little trail, make a definitive blast that goes off in a particular direction in streaks. We can start, though, with an old composition. I can just go back to Wand Sphere, and duplicate this. Edit > Duplicate. I'm going to rename this, wand blast.
And open that up by double clicking. There's a old simulation. Let's start changing that. I'm going to go up here, and start his birth rate. It's going to be a very short blast. So, on the first frame, I'm going to key the birth rate starting at a low number of three. On frame six, I'll essentially turn it off by entering zero. I want the particles to survive longer, so I'm going to change the longevity to one. Under Physics, I'm going to give it a different initial style of animation. Instead of explosive, I'll change it to direction axis.
Particles will go along a single axis. The speed of that motion is controlled by velocity. I'm going to increase this to six. And then I'm going to leave gravity at zero, because we're going to go in a straight line without falling. Change the particle type though, so Particle > Particle Type, back to line. Let's play it back. There's a short blast. I'll note the direction the particles are moving are controlled by the direction axis.
Which in our case is fine, so we don't have to change it. Now ready to integrate this into the plate. Let's go back to Plate Build. And drop this new composition down here below wand sphere. I'm going to have this start on frame 17. There's the blast. We're going to have to key the position changing over time. Let me go ahead and expand Transform section, and key the position. And move it into the correct place at the tip of the wand. Now it'd be great to have it fade quickly in and not be it's full size so immediately.
So on the first frame, frame 17, I want to change the scale and key that to 25. That very rapidly made that bigger. So on frame 19, I'll make it 100 and update the position. Now it's all pretty intense in terms of it has very hard edges when it's small. So I can also add a blur and animate that over time. Effect > Blur & Sharpen > Fast Blur. I'm going to key that, starting at a very high number, 100, and then quickly reducing to six, just in one frame.
I'm going to reduce the opacity, just to make it a little less opaque. So 70% opacity. And then also change the blending mode to make it more interesting. So, instead of normal, let's try Linear Dodge. That inserts a little bit of white into it. Now, to make it pop a little bit more so it's a little bit more intense, yet slightly transparent, I can add another effect. And in this case Glow would be perfect, so Effect > Stylize > Glow. Initially comes in very intensely green, but we can change that. I'm going to reduce the threshold though, and that determines what pixels glow.
The lower the threshold, the more glow. So 33 for that. The glow radius is how far the glow spreads out. I'm going to reduce that slightly to eight. And the intensity is the strength of the glow. Let's go a little bit higher, 1.6. Now, at this point, it's very green, very solid green. Let's get some variation back into it. We can do that by changing the glow colors. We'll change it from original colors to A and B colors, which we get to select. Now already, when we change that, it becomes more interesting.
Let's change color B to dark green. I'll leave color A at white. So there's some more variation. At this point, the blast is traveling in a perfectly straight line, so I'll have some fun by adding some distortion to get it to wiggle through space. We can do that by adding a turbulent displace. So Effect > Distort > Turbulent Displace. And already it becomes more curvy. Going to increase the amount, which is the intensity, so it's more of a bend there.
We'll leave the size at 100, and then we'll increase complexity slightly, to give it more variation in the bumps. It'd be great to have that curviness change over time, almost like a worm moving, or a fish. What we can do there is, key the evolution changing over time. So on the first frame, frame 17, I'll go ahead and activate the time icon at zero, and then say 25 where the beam disappears or the blast disappears, change that to six revolutions. What that does, is it cycles through different slices of the noise that are used for the distortion.
Now once distortion's added, it's really going to really offset the blast, it's going to be in a different place, so I need to update the position animation. Now I need to keyframe this until it disappears. Let's play it back. So there's a nice, quick blast. So once again we were able to use a standard Particle Effect, make a few adjustments to get a very different look of the particle simulation.
- Setting up the project in After Effects
- Generating a particle blob
- Hand tracking particles into the plate
- Patching the background
- Creating particle puffs, sparkles, and explosions
- Motion tracking elements
- Color grading shots
- Keying green screen
- Layering particles