Compositions are the basic work space of After Effects - think of a composition as the canvas upon which you will composite and animate your graphics. When you create a new composition you set a variety of parameters such as dimensions, duration and frame rate based on the specs you need for your finished video. All of this is set through the composition settings window which comes up when you create the new comp...there are several ways to do this:
- From the File Menu choose "Composition>New Composition..."
- Use the keyboard shortcut Apple-n
- In an empty part of the project window, control-click (right-click on a 2 button mouse) and from the contextual menu that pops up choose "New Composition"
- Click on the New Composition button at the bottom of the project window (it's the third button from the left with a square icon on it).
Regardless of which method you choose you will be presented with the Composition Settings window:
Start by giving your new composition a name (1) - you can have as many comps in a project as you like, so make sure to give each one a unique name which is easy to identify. Next you can choose from a drop down menu (2) of presets - most common formats have presets here, so you may not need to change many of the other settings. For class work we'll be using the medium preset; if you are working on a project you intend to put on DV tape or DVD you should use the NTSC DV preset (pictured) or the NTSC D1 setting (if you are going straight into a DVD authoring program.
Below this are some options for setting the width and height (in pixels) of your composition (3), an option to lock the aspect ration (with that checked, changing the height will automatically change the width, and vice-versa), and a drop down menu for "Pixel Aspect Ratio". Computer displays use square pixels, but most broadcast video formats use rectangular. For work that will only be show on a computer monitor you can use the square setting, otherwise use the D!/DV NTSC(0.9) setting.
Next you can set the frame rate (4) - this is how many frames per second (fps) the video will play at. Broadcast video uses 29.97 frames per second. You may want to change this if your intended destination is the web - lower frame rates translate into lower data rates, but otherwise 29.97 is a good setting for most projects.
Finally, at the bottom you have options for resolution - this only effects previews and can be easily changed later, so leave it at full for now. Start timecode can generally be left at the default setting. What is more important is the Duration (5). This is how long your composition will be, and it uses standard SMTP timecode - Hours;Minutes;Seconds:Frames. The code visible in this shot is for 30 seconds. Make sure you set this to a value appropriate for your project.
Once you've set all your options, click "OK" and the window will close, the composition will appear in your project list, and two new windows will open - the comp window and it's associated timeline. Now you are ready to begin adding your imported footage to the comp and start creating your video.