What is a keyframe? What are the uses and importance of keyframes in designing and making motion design? How many types of keyframes does After Effects software have?
Motion design is nothing but the artistic game of the motion designer with light, sound, and movement. In motion graphics, inanimate elements can move and do something to convey a specific message to the viewer. It is not supposed to tell a long story in a motion graphic. Logo motion, which is the animation of a brand’s logo, is made to distinguish and attract the attention of users.
But how can a motion designer play with inanimate elements and give them any movement they need? You must say that with the help of powerful motion graphics design and creation software such as After Effects. Quite true, although not a perfect answer.
Read this content till the end to find out the complete answer to that question. Note that what you read in this content is included in the category of specialized motion design training.
Table of Contents
The role of keyframes in motion design
The motion designer creates motion graphics using the tools and facilities that exist in software such as After Effects. One of the most important and key tools that allows the motion designer to create a moving object with special features in the software is keyframes.
What is a keyframe and how can it be defined very simply and clearly? To understand the keyframe and its essential role in making motion design, it is necessary to take help from an example. Imagine that we are going to make a 30-second motion graphic in which the movement of a ball is shown. The ball is motionless on the ground, then it is shot, hits the wall, and returns and hits the ground twice until it finally stops in a corner.
The motion designer must create a frame for each moment of these 30 seconds. The final video motion is the result of combining and pasting these frames one after the other. The ball or anything else that is supposed to be animated in the software environment has properties. The most important features that the motion designer deals with are Position, Scale, Rotation, and Opacity. Motion Designers can give those important properties of the ball different values, usually a small amount.
So, it should change the location of the ball several times, between several points (locations), and at certain times, and rotate it at some moments of the motion graphics. At some point, the ball may need to move faster or fade before stopping. For each of these movements, in each of which one of the characteristics of the ball changes, a keyframe must be created, and within the framework of that keyframe, the amount and rhythm of the changes of that characteristic must be defined and specified.
To change any property of an object during video motion, keyframes must be created and the value of that property must be specified within those keyframes.
Interpolation in motion graphics
When the motion designer defines the above keyframe in the after-effect software, the software itself calculates the frames between the two keyframes based on the values defined in the keyframes and interpolates the motion path on a straight line between the two locations. This default and automatic process is called interpolation.
The role and importance of keyframes is that the motion designer only needs to create the main keyframes for the software to interpolate the intermediate frames on the same basis. In other words, the motion designer doesn’t have to create every single frame. It is enough to define and specify the keyframes.
Types of interpolation
Interpolation is temporal or spatial. That is, the software calculates both the movement path between two keyframes and its speed.
1. Temporal Interpolation
This type of track interpolation calculates and reproduces the changes of that characteristic (speed of movement, speed or slowness of rotation, and fading or enlarging and shrinking of the object) in the time interval between keyframes.
2. Spatial Interpolation
This type of interpolation calculates the movement path of the object (smooth, curved, or…) between keyframes.
In After Effects, when a keyframe is created for a feature, its spatial and temporal interpolation is automatically calculated and applied by default. For example, keyframes generated for a spatial feature have linear temporal and spatial interpolation. That is, the object moves from the starting point to the endpoint on a smooth path with a fixed and specific speed that is neither accelerating nor decelerating.
An important question that arises is how the motion designer can change the default values and speed in the keyframes it creates for each feature. Because there is no other way and it is possible to move or show movement in motion graphics by using the game with the type of interpolation of the object’s properties and its values. After Effects provides motion designers with tools for this.
Types of keyframes in After Effects
There are several types of keyframes in After Effects. The difference between these keyframes is in the different interpolation methods they apply to the intermediate frames. For example, the default keyframe of After Effects works with the linear interpolation method. Linear keyframe is the simplest method and at the same time gives a very dry and mechanical movement to the object.
In addition to linear keyframes, After Effects has 4 types of keyframes with 4 other types of interpolation.
The types of keyframes in After Effects are:
1. Auto Bezier keyframe
The name of this keyframe is derived from a type of mathematical curve (Bezier curve). If the motion designer wants the ball to move in a curve instead of moving in a straight line, he chooses Auto Bezier keyframes. The important thing about this keyframe is that the Motion Designer cannot change the curve. The software itself calculates the curved path between two locations in the keyframes.
2. Continuous Bezier keyframe
If it is chosen to move the ball from one point in the keyframe to another point of this keyframe, the motion designer can specify the settings related to the type of curve and the rate of the feature change in the keyframes.
3. Bezier keyframe
The difference between this curved motion and the previous two is that Bezier keyframes give the motion designer the most control to set the type and speed of the curved motion. In this keyframe, the motion designer can give different settings to the software for the starting keyframe than the second keyframe. This feature is not available in automatic and continuous type.
4. Hold keyframe
By using this keyframe, the motion designer can stop the movement of the object at a specific moment of the frame and keep it (freeze) until the end.