Join Lee Lanier for an in-depth discussion in this video Adapting stock footage, part of VFX Techniques: Space Scene 02: Compositing in After Effects.
Now we're going to move on to something completely different. We're not going to use any render passes or render layers. Instead we're going to use stock footage. We're going to use stock footage of an explosion and tweak it so it looks like something futuristic. Let's give that a try. File>Import File. This is in the Explosion folder. And here's the explosion that's a 16 frame PNG sequence the spherical explosion that gets bigger and bigger. Let's bring that in. I'll keep that in Asteroid folder then drag it down into AssembledScene below the ship.
I'll start this at frame 96. And there you can see it, start to blow up. Now, so we can see through it to the asteroid, I'm going to change the blending mode to Screen. Then we need to scale it and position it so it's centered in the right place. Let's go to the frame 100. And then we'll start to scale at 100, the current size. And then let's say it by 113 towards the end here. We're at the end of the sequence. We'll go ahead and scale it down. So this is going to slow the overall scale that's built into the footage.
So 100 to 50. We're also going to fade it out because it doesn't disappear, just is there until the end. In fact, it clips the edge of the frame. So is a good thing to emulate also so let's say that it should be faded out by 111. Here, because we can see it hit the edge, we'll make that zero. We'll back up and start with 100. Now, we need to position it so it's in the center, of this asteroid here. So I can just move it, and try to find the center.
I'll give you some values. I'm going to key this. There at 100. Let's try 710, 236. And then by the end it's going to drift downwards a little bit, just like the asteroid chunks. Let's try 770 and 294. Let's play it back. It hits on the bottom right side of the asteroid about right here and there it goes and it fades away.
Now in order to make it a bit more futuristic we can change the color and once again we can use a Hue Saturation. Let's try to, go towards green. So let's try 60, or maybe 65, to reduce saturation so as not to overly intense, negative 30 and lightness at zero. That's all it takes, we've just shifted the color towards green and now it's much more futuristic. We have other elements that are also green we'll bring in later.
Now we can also tint the chunks and the bits so they take on some of that great explosion while we're at it right here. So let's go to bits and let's say at 105 where's a decent amount of green. It's starting to fade away. We can go ahead and look at the current effects and there's no hue saturation so we're going to add one and turn this screen and key it. So let's try, upper 70s, let me zoom in here so we can see this. We need to, we can solar this.
So let's try 79, more saturation so we can see that green. 80, there it's starting to come through and not too bright. Negative 20. We can go ahead and key all these things here if you turn on the time icon for channel range. Let's go to 120. When the explosion's pretty much gone, and these things are starting to float around, and we can return it back to its normal color, 0, 0, 0. I'll turn off the solar for this and we can actually copy this hue saturation to the chunks to get the same coloration.
Now, when you copy an effect and you want the key frames to be in the same place, it's best to go to the frame where there's the first key frame, then thick on the effect name. Controller> Command> Copy. Or C, and then go up or down to your other layer and paste without moving the frame number. Cmd or Ctrl+V to paste. And that pastes the entire effect with the animation right in the correct location. So, now we have a greenish cast while the explosion still around that slowly fades out.
So that shows you, you can use some preexisting footage and once again, tweak it through Effects and Transforms to make it something completely new.
- Setting up the project in After Effects
- Combining background elements
- Layering render passes
- Adapting stock footage
- Adding After Effects particles
- Color grading the composite
- Adding camera shake and grain