Working with Key frames in Adobe after Effects
As a beginner, working with Adobe after Effects can seem complicated. Many newcomers are scared off by its daunting user interface – looking neither like photo editing software like Adobe Photoshop or film editing suites like Apple Final Cut. So many buttons and expressions yet so little you know about them.
Don’t fear! This article is here to help you with an important part of After Effects’ workflow: the key frames in the composition window. This is what all animation in the software is based around. The purpose of this guide is focused on making you understand the concept of key frames rather than how to technically use them.
Regular, old-school animation is done by individually creating each frame by hand. For example: if you wanted a ball to bounce over screen, the animator would draw each frame – in the air, slightly closer to the ground, even more close to the ground, really close to the ground and hitting the ground. With modern motion graphics this time consuming process is no longer needed, thanks to the wonder that is key frames. A key frame is just what it sounds like: a frame that is key to the animation.
To keep the ball metaphor going, an animator working with key frames would place a key frame when the ball is at the top of the drop, and one at the bottom. The software then calculates what happens in between the different states, called twining. Using this method, we can animate position, scale, rotation, opacity; blur levels – basically anything that can have a numerical value. You can even animate distortion of clips to create funny facial expressions for example.
You can also use easing, a process when the computer calculates the speed of change between the key frames. For example, if you animate a car starting and driving away, you would want the animation to seem realistic in that the car slowly accelerates. In order to do this, you place one key frame at the start of the driving stretch and one at the end, and apply the easing. Now the car will start off slow, and finally reach its driving velocity. Combine this with key frame-animated wheels and – viola – it took you seconds to do what would have taken hour’s years ago.










