Alpha Mattes in Final Cut Pro
An alpha matte defines areas of the screen to be dropped out from the visible picture. In fact, when you design any title within Final Cut Pro it is treated as an alpha matte. The title is automatically keyed over a video image below it.
This characteristic of titles that allow you to automatically see a video image underneath them is referred to an alpha channel. The alpha channel represents the transparent area of the image. The matte represents the solid part of the image.
A great feature of Final Cut Pro is the ability to change what is placed into the matte. This is done by creating a new video track and placing a clip directly above a title. By changing the composite mode of the new clip, you can fill your text with a video image.
When you are finished with this exercise you should have something that looks similar to this. The 'Jamaica' title is filled with the water from the pool. The finished track layout in the timeline window is shown below.
Here are the basic steps to complete this Final Cut Pro training tutorial.
Create a new sequence in the browser window and give it a name. Double click on the new sequence to load it into the timeline window. Find a clip and drag three seconds of it directly to the timeline on V1.
Use the Title 3D, title tool to create a large title.
Use a point size of 96. Leave the color of the title white with no additional effects. Clip the apply button when you are done.
ADJUSTING THE TITLE IN THE VIEWER
After you click the apply button, the title will be visible in the viewer window. This title needs to be edited directly above the clip you have chosen for V1. You can save some steps, by using the superimpose feature within the canvas window.
Make sure you place your position indicator in the middle of the V1 track. Then drag the title from the viewer window into the superimpose box within the canvas window.
By dragging your title into the superimpose box, Final Cut Pro will automatically create a new track for you with a title that matches the duration of the clip underneath it. Otherwise you will need to trim the clip on V2 to match the clip below it.
The next step is to patch your source track to the V2 track, so you can easily superimpose the third layer. Also, make sure your position indicator is parked over your title within the timeline window. Final Cut Pro will use the position indicator as a reference of where to superimpose your next layer.
Next, find a clip that you want to use as the 'Fill' load it into the viewer window. Drag the clip into the canvas window and drop it inside the superimpose box. This will automatically place the clip onto V3 and it will match the duration of the clip below it.
Before continuing, you should have a timeline that looks similar to the one below. You should have all three layers stacked directly on top of each other. Your title should be in the middle of the two layers.
The next step is to change the composite mode of V3 to it fills inside the 'Jamaica’ title' . After you have all three video layers in place, change the composite mode of the top layer V3 to Travel Matte - Alpha. To do this: Control click (or right click) on the V3 clip and select Travel Matte- Alpha. This will cause the clip on V3 to fill inside the 'Jamaica’ title'.
The finished composite should now look similar to this.
ADDING A DROP SHADOW OR GLOW
Adding a drop shadow or glow to the 'Jamaica’ title, it will really help it stand out from the background. This can be tricky. You need to do this step after you have completed the basic composite from the first exercise.
Drag your clip from V3 and move it up one layer to V4. Your timeline should look similar to the example below.
Make a copy of your title from V2 onto V3. This is done by holding down the shift + option keys while dragging the clip to make an exact copy above itself.
Load the bottom text layer, which is on V2 back into the viewer window. You can now change the clip on V2 to include a glow or drop shadow. The title on V2 will stick out from the title on V3. Double click on the title that is on V2.
After you double click on the title that is on V2, it will load into the viewer window. Within the viewer window, click on the controls tab. Then click on the title 3D box to make some changes.
If you choose to add a glow, you may want to take a look at the example below.
EDITORS NOTE:
When making changes to your title, Title 3D requires that all the characters be highlighted. This produces some strange results when making adjustments, because it is hard to see what you are doing with all the characters highlighted. Don't worry, just de-select the characters and preview your title before you exit.
The final composite should look similar to this graphic illustration. Notice how the glow helps separate the filled text area from the background.
