Join Mark Christiansen for an in-depth discussion in this video Common After Effects terminology, part of After Effects CC 2019 Essential Training: The Basics.
- [Narrator] There are a few common terms it's really helpful to understand, to work with After Effects. In this lesson, I'll focus on the ones that apply to After Effects it's self. Before we look more broadly at video production terminology. We'll start with key frames. Many people have some idea what a key frame does, but it's an easy concept to misunderstand. It goes all the way back to the early days of Disney animation. When the most talented artists, would draw only the key frames. The top of a leap, the deepest crouch, the moment of impact, and then let junior artists add the in between frames to complete the animation.
After Effects and other computer graphics programs effectively do the same thing for you. Letting you set specific properties on one frame along with a key frame, another set of values at a separate frame, using another key frame. And then generating the between frames for you with mathematical precision. Property is the name for any value in the timeline that can be key framed or adjusted. In After Effects all properties belong to a specific layer and can be found by twirling down that layer.
Literally clicking on arrows to the left of the layer to reveal names and values of properties nested within. Layers are the building blocks of After Effects. Everything you make is created in what is called a composition, which is made up entirely of layers. These layers can contain many different things. Video, audio and still images, but also 3D cameras, lights, blank frames called solids, in which you can generate animated effects from scratch and much more. Timecode is more or less what you probably think it is.
The timing at a specific point in a video. But to be super specific about it video is always made up of seconds of time divided into a given number of individual frames. This can be any number you want, but the standard ones are around 24 frames per second for film, 25 for European video, and 30 frames per second or more accurately, 29.97 frames per second, don't even get me started on that, for North America. Render is the process by which you create a video file that can then be played outside of After Effects.
We need renders because the After Effects files themselves, are too complex and slow to play back outside of the application. And they rely on outside source files, which are never over written by After Effects it's self. You import video and still into After Effects, and export new video and still out of After Effects by rendering. Codec and format determine how a given video is recorded. If you've ever heard of quick time, that is a file format the can contain video and audio using a specific codec.
The codec literally means compression, to co part. And decompression, dec, and it's purpose is to make the file size small, play back smooth, and image and sound quality as high as possible. Alpha channel is in someways the most essential component of After Effects. It specifies where the transparent areas of a frame are pixel by pixel. Each pixel can but fully transparent, fully opaque or somewhere in between, and this transparency is the primary method that allows you to stack layers without the top one obscuring all those behind it.
Just like in Photoshop. Every image in After Effects effectively has four channels. Red, green and blue, like any digital image, and a fourth channel for transparency knows as the alpha. So those are some terms that maybe familiar from other graphics and video applications. Now let's look at some other terms that are common to the type of video production you do in After Effects.
- After Effects and industry terminology
- Six foundations of After Effects
- Setting up a composition
- Working with layers
- Animating compositions
- Applying effects, including lights
- Working in 3D
- Rendering projects