Let’s say we want to animate a character reaching for a cup. One way to approach this would be to draw every frame leading up to the character picking up the cup, but that’s a lot of work before we really know if the action reads well. That’s where key poses come in. Key poses are the main drawings that show what the character is doing, where the action turns, and what the audience needs to read. Before you get started on your in-between frames, a handful of key poses should do a good job of telling you what the action looks like.
For example, in our reaching example, we may have a resting pose, an anticipation pose where the character’s weight shifts back a little bit, the main reaching pose, and the final pose of the character holding the cup. We can play through these drawings to see if they convey the action correctly. At this point, we don’t necessarily need them to look smooth. They’ll likely look choppy, but that’s okay. We just want to see if the silhouette, gesture, and overall direction of the action makes sense. If we think the character’s motion doesn’t read well, throwing more frames into the mix will most likely just cover it up instead of fixing the issue.
Key poses also allow us to more easily manipulate our timing. The placement of our key poses on the timeline dictates how quickly or slowly the action happens. For example, if we have a quick reach, we might only have a handful of frames between the initial resting pose and the final pose of the character holding the cup. Conversely, if we want the character to take their time reaching for the cup, we might give the reach a few more frames to complete. Or, we might even add a few frames of stillness after the character begins reaching to give the action a little more emphasis. Being able to test out different timings before we have all of our in-between frames is beneficial because we don’t need to redraw everything if we want to experiment with timing. All we need to do is adjust the spacing of our keyframes.
We can also use the key poses to ensure our action moves along the right path. Take a look at the position of the hand (or whatever body part is moving) in each key pose. If the positioning results in a natural arc, we’ll have a solid foundation to draw our in-between frames against. If the hand moves in a strange direction or follows a particularly straight line, go back and revise the key poses until they look right. Using onion skin can be especially helpful for this when you’re animating digitally since it allows you to see a preview of the drawings surrounding your current one. However, even flipping back and forth between two rough sketches can be enough to determine whether the path of the action is what you want it to be.
During this stage, it’s best to keep things rough. A few circles, basic shapes, and strong lines of action are typically sufficient to give you a good sense of how your animation will play. Adding too many details like clothing, facial expressions, or backgrounds can distract from the pose, which will make it difficult to tell if the pose actually works. This is why we want to focus on getting the poses down before we start adding the details. Not only does simplifying the poses make them easier to evaluate, it also means they’re easier to change if needed. If we realize that our reaching pose needs more of a lunge or that the arm should reach further, we can adjust those details much more easily on a rough sketch than a fully rendered drawing.
Once we have solid key poses in place, our in-betweens have a job: fill in the gaps between the key poses rather than come up with a whole new action. Start off by drawing a few of the in-betweens and then play through them to see how they look. We want to see if the action flows smoothly and still communicates the intended movement. We may decide that there needs to be one more in-between in a particular area or that there shouldn’t be as many in-betweens in another. Knowing how to evaluate your key poses before you commit to drawing out the entire sequence can save you time and headaches. It’s not about having more in-betweens; it’s about knowing what each frame adds to the animation before you start fleshing it out.
