This tutorial will allow you to develop a deeper understanding about mattes, and how they can be used to apply texture and transparency to your layers in After Effects, by putting together a five-second television bumper in Adobe After Effects.
Starting with some basic images (and the AE project file included in our download), we’re going to dirty up some clean computer type to give it a realistic feel. You’ll use 3D space for positioning the image, and use the images and textures supplied to create the five-second effect shown in step 10.
You will then learn how to nest compositions, use a Null object to control camera movement between scenes, and gain a better understanding of the Collapse Transformations switch.
Remember, the key is to have fun, and apply what you’re learning to your own projects.
Adobe After Effects
Time to complete
The resources for this tutorial can be downloaded from here
A matte is completely independent of the alpha channel, but works in a very similar fashion. A matte is any greyscale image that is used to define transparency. Each layer in After Effects can have its own matte. This can be done in several ways, but one way is to use a layer’s Track Matte setting.
Create a new composition called ‘Scene 1’. Let’s start with the words “Coming Up” typed out with the AE Type Tool, as above.
Next, bring up the Modes column. If you cannot see the Modes column, right-click the column header, go to columns and select Modes. On the right side of the column, you see a TrkMat section. This allows any layer to use the layer immediately above in the stack order as a matte. Currently it has no options, because there is not an image above the layer in the stacking order.
Place the image texture1.jpg just above the type layer. Now, under the Track Matte menu, four options
will become visible.
As this image is a JPG, it cannot contain an alpha channel (embedded transparency). However, it does contain quite a bit of Luma (short for luminance) information, or greyscale imagery. A ‘Luma matte’ disregards the pictures colour information and only looks at the greyscale information.
The Track Matte function lets us use the texture of this image as a matte, therefore applying that greyscale information to the transparency of the text. This is a great way to make ‘perfect’ computer type look more realistic. The other wonderful thing about track mattes is that they’re independent of the layer below. Need a mask that doesn’t move with the layer? A track matte is a perfect solution. An important note – if the track matte layer does need to move with the layer below, it can simply be parented.
Now you need to set the matte filter. Let’s transfer imagery to the transparency of a layer. Refer to the image included with this tutorial, ink_matte1.jpg. This is a greyscale ink splatter image. There is no transparency in the image, but, as we’ve learned, a greyscale image is just transparency in the waiting.?We can easily apply this JPG to the transparency of another image.
This time, instead of a track matte, an effect called Set Matte will be used. Create a new black solid: Layer>New>Solid. Call it ‘Ink1’ and make it the size of the comp.
Next, you apply the effect. Click Effect>Channel>Set Matte. Add the file ink_matte1.jpg to the comp and turn off the visibility. In the Set Matte settings, find the Take Matte From Layer setting and select ink_matte1.jpg. In the Use For Matte setting, set it to Luminance. Also, check the Invert Matte checkbox.
Essentially this image works the same way as a track matte. The luminance is used to define the transparency. This allows any layer in the comp to be used, and any part of the image: such as red, green, blue, channels, luminance, and saturation.
One thing to understand with this effect (and any effect in After Effects that references another layer like this) is that it only looks at the source of the layer. In other words, when the layer ink_matte1.jpg is defined as a matte with Set Matte, none of the transformations, effects, and masks of that layer will be visible to the Set Matte filter, only the source image. However, the solid ‘Ink1’ can be moved wherever we want.
Repeat the above process for the image, ink_matte2.jpg, so you have this image.
You’re now ready to position the image in 3D space. Turn the type and the ink solid layer into 3D layers by checking the 3D switches for these layers in the switches column.
Switch to Custom View 1.
You’ll now see these 3D elements from a different perspective. Grab the Z handle of the type and drag it forward in Z space. With the Ink layers, grab the Z handles and push them backward in space.
A composition placed inside other compositions is called a ‘nested’ composition (or sometimes a pre comp). There are many reasons to do this. In this case, breaking the animation into two compositions will simplify the management of the project. Create a new standard definition composition called ‘Main’. Place comps Scene 1 and Scene 2 into ‘Main’. Then, click the 3D switch on both layers. Select the layer for Scene 2, and type ‘P’ to isolate the position property.
Set the position of this layer to be 2,500, 300, 3,000 in X, Y & Z. Then press Shift-R to view the Rotation property and orient the layer 45-degrees in the Y axis.
Go to Layer>New Camera (default settings). At this point, hit the C key, or go to the tools and select the Orbit Camera tool. Move your mouse around a bit in the comp window. This will change the position of the camera, but not the point of interest. Notice how flat the Scene 1 appears to be, despite the fact the layers are in various locations in 3D space. This is how nested compositions behave, by default.
Click the Collapse Transformations Switch for both layers.
This switch ensures the 3D properties of the layers inside the composition will be retained. Now, orbit the camera around. You’ll see how the layers retain their 3D properties.
In the images above, the left image shows before Collapse Transformations – the layers are flat and cropped.
The right image shows after Collapse Transformations – layers are uncropped and in 3D space. You can see multiple scenes could be nested into one main composition. This method keeps projects organized, and easy to manage.
Next, you’ll move a camera between the scenes. Use the Undo command to reset the camera to the original position, or delete it and create another camera. Hit the v key to access the Selection Tool. Create a Null by going to Layer>New>Null Object.
By default, it will be called Null followed by an integer.
I prefer to rename the Null in accordance with how it is being used.?With the Null selected, go to Layer>Solid Settings and name the Null to be called Camera Null. Make the Null a 3D layer.
This is critical. A 3D camera cannot be controlled in a useful manner by a 2D Null. Make sure the Parent column is visible by right-clicking the Column header in the comp window, and selecting the Columns>Parent option.
Parent the Camera layer to ‘Camera Null’.
Now the Camera will do everything that the Null does: move, rotate, scale, etc.
One thing I like about this is that it gives the user a convenient camera controller in the middle of the comp window. Because the Camera is parented to the Null, the Null will not appear to move in the Active Camera view. Click-&-drag the Null, and the camera’s position and point of interest will follow. Rotate the Null, the camera will rotate around the Null’s anchor point.
Notice, however, that moving the Null will, most likely, feel a little odd at first.
Dragging the Null to the right moves the camera to the right, which makes the objects in the scene move to the left.
We’ll now animate the camera. Select the Comps ‘Scene 1’ and ‘Scene 2’. Switch to the Top view, and zoom to 6.25 per cent.
You’ll be able to select and see the positions of Scene 1 and Scene 2.
Select the Null, and hit p to show its position, and Shift-R to add Rotation. Place your Time Indicator at three seconds and create keyframes for position and Y rotation of Camera Null. Move to 4 seconds. Set the Null’s Y orientation to -45º and set its position to 2,500, 200, 300, just like Scene 2.
Switch back to the camera view to preview your animation. You can now see how it can be quite easy to divide scenes into compositions, nest them into one comp, and create camera moves between them. Using a Null makes camera movement between the nested comps much easier.
A special thanks to Andrew Kramer of videocopilot.net for providing images from his new Riot Gear collection, a collection of high-definition organic stock footage.