Join Steve Wright for an in-depth discussion in this video Compositing the mantis, part of Compositing an Alien Portal in NUKE.
- We'll start the alien portal composite by compositing the mantis character. I've got it loaded here on the timeline, and as you can see, I've got a nice alpha channel and I also have a shadows layer, OK? There's two channels in there, we have a contact shadow, we can see that in the alpha channel here. Now, the contact shadow is where his feet are going to step on the ground, but this render has this big white out here which is of course a rendering mistake, we get that all the time, so we'll have to fix that when we go to do the contact shadow.
Fortunately, the ground shadow doesn't have anything to fix. The lighting for this scene is a very soft overcast day, so our shadows are very soft and diffused. We'll be looking at how to do the shadows in the very next video. So let's go back to our rgba here, and we'll put the alpha channel back in the viewer. The background plate, is 200 frames long. In the very beginning this pillar is in our way and is covering up most of the scene in order to do a dramatic reveal.
So we'll see in a video shortly how we're going to restore the post, because we have a composite of our character that's actually behind the post for the first few frames. Notice that the mantis doesn't start moving until frame 25, OK? The reason is he's actually behind the post up until frame 25, so I'm going to set an in point here and I'll set an out point at the end of the shot. That way we can focus on the actual active part of the shot. So, we're ready to comp the mantis with the background so I'll just select the Read node and type M on the keyboard to get a Merge node, hook that up to the background and off we go, so there we are.
And as you can see, we get past frame 25 and the mantis is behind our pillar. Now, before we go any further, I want to do a basic color grade to the background. So let's select that background node, type G to get a Grade node, and let's label this Grade node, "darken BG," we'll darken the background here, and I thought that a gamma of 0.8 looked pretty nice. Here we go, more dramatic, you know? OK, we've got a basic comp of the mantis set up, we're now ready to look at the shadows in the very next video.
Each step of the process is rich in valuable production techniques, but is best for artists who are already familiar with NUKE. For more training on the basics, see Nuke X Essential Training.
- Compositing the alien character
- Creating holdout mattes
- Camera tracking
- Animating the portal rays
- 3D rendering the effects
- Adding interactive lighting
- Animating a flashing light
- Finishing a NUKE composite