This guide shows how to use a light wrap technique to integrate a figure into a background in After Effects. This is a great way to make your composited footage look more realistic.
- Add an Interesting Background Once you have keyed out the green screen, you can add an interesting background to your composition. To do this, create a new solid layer and apply a Cell Pattern effect to it. You can adjust the settings of the effect to create a variety of different patterns.
- Add Color to the Background You can also add color to the background using the Colorama effect. This effect allows you to change the hue, saturation, and brightness of the background.
- Create a Light Wrap To create a light wrap, duplicate the garbage matte layer twice. On the second garbage matte layer, set the Track Matte to the Alpha Inverted matte of Garbage Screen. This will create a mask of the transparency layers. Next, add a Simple Choker effect to the top garbage matte layer. This will help to smooth out the edges of the mask. Finally, add a Gaussian Blur effect to the top garbage matte layer. This will blur the edges of the mask even further.
- Precompose the Light Wrap Select the two garbage matte layers and right-click to precompose them. Name the precomposition “Light Wrap”.
- Add the Light Wrap to the Figure Layer Duplicate the red solid layer and drag it above the garbage screen layer. Set the Track Matte of the red solid layer to the alpha channel of the Light Wrap precomposition. This will add the colors from the background to the edges of the figure. However, the effect may be too strong.
- Change the Blending Mode and Opacity To fix this, change the blending mode of the red solid layer to Color Dodge. This will blend the colors from the background with the colors of the figure. You may also need to lower the opacity of the red solid layer to reduce the effect.
- Add a Light Wrap to a Traditional Subject Matter This technique can also be used to integrate a figure into a more traditional subject matter. For example, you could add a light wrap to an ocean scene. To do this, drag the ocean scene layer above the red solid layer. Then, invert the layer by going to Transform > Flip Horizontal. This will make the light in the ocean scene come from the same side as the light on the figure. Duplicate the ocean scene layer and the light wrap precomposition. Drag the ocean scene layer above the light wrap precomposition. Set the Track Matte of the ocean scene layer to the alpha channel of the light wrap precomposition. Change the blending mode of the ocean scene layer to Color Dodge and lower the opacity to reduce the effect.
This is just a basic overview of how to use a light wrap technique to integrate a figure into a background in After Effects. There are many other techniques that you can use to achieve the desired effect.
Now that we have successfully keyed out the green screen, let’s add an interesting background to take advantage of the alpha channel. To do this, click on the Red Solid. Then in the Effects and Presets type in “cell”. Drag Cell Pattern on top of the Red Solid.
In the Effects window, click the stopwatch on each of the attributes to set a keyframe. Drag your playhead to the end of the composition. Now let’s change some of the attributes. We can change to plates. We can add more dispersion. We can change the size. We can change the evolution. Now we have an animation behind our figure. Again in Effects and Presets, type in Colorama. Drag the Colorama effect onto the Red Solid. In the Output Cycle, click the stopwatch to set a keyframe. Then drag your playhead to the end of the composition. Now select another palette. I’m going to select Deep Ocean. Now After Effects is keyframing to color palette behind our figure.
To make our figure integrate more into the background, we can use a technique called a light wrap. To make a light wrap, select the Garbage Screen layer and duplicate it twice by pressing Command - D. On the second Garbage Screen, set its Track Matte to the Alph Inverted matte of Garbage Screen. Then select the top Garbage Screen. In Effects and Presets, type choker. Drag the Simple Choker onto the top Garbage Screen. Solo out lower layer so we can see. Notice that now we have an inverted matte of only the transparency layers. If we add choke to the matte it goes inside the figure but it still has this harsh edge.
To get rid of that harsh edge, we can drag a Gaussian Blur on to the top Garbage Screen. Blur out the edge and now we can precompose these two Garbage Screens. Select them both, right click and then precompose. Label this Light Wrap. Unsolo the layer. Now duplicate the Red Solid layer by pressing Command - D. Drag the Red Solid layer above Garbage Screen. Then set its Track Matte to the the alpha channel of Light Wrap. As you can see it is now adding those colors to the edge of the figure but it is way too powerful.
So to fix this, we change the blending mode to Color Dodge. It is still a bit too powerful so what we will do it press T and lower the opacity. Maybe something like 25 percent because this is a very bright scene. Now if we zoom in, and we toggle the light wrap layer on and off, we can see how the skin tone and the sweater start to seem like they are glowing from behind from the background. This is a great technique to blend your different layers together.
Let’s do it with a more traditional subject matter. Here I have an ocean scene. I’m going to drag it on top of the Red Solid layer. And now notice that the light from this layer is coming from this side. I need to have the light match the light of the figure. To do this, I will invert the layer. Go to Transform - Flip Horizontal. Now the light is coming from the same side as the figure. Press Command - D and duplicate ocean. Also, press Command - D and duplicate light wrap. Now, I will drag the ocean composition up above the other light wrap. I will change its Track Matte to alpha matte light wrap. Change its mode to Color Dodge. Then press T for opacity. And lower the opacity down. If I toggle this layer on and off you can see that it integrates the figure much more into the background. There are many more techniques that I will show you in future videos to color correct your keyed footage with your backgrounds.