How do film-makers keep track of where they are in a complex stop motion animation scene?

Question

In the past I've played with some of those smartphone stop-motion animation apps, but it can be difficult to keep track of where you are. Even just moving a couple of limbs while "walking" a character can be tricky - you need to remember where to move each limb in the next frame, slowing down the rate of movement in (say) a swinging arm, knowing when the arm has finished swinging forward and needs to start swinging backwards in the next frame, etc, etc.

Some of these apps assist by letting you "overlay" the previous frame over the live view, but how do studios keep track of a complex scene containing dozens of characters and objects all being animated at once? Is it the same principal? If so, how would this have been achieved before digital, where creating an "overlay" would have been impossible?

Answer 1

Storyboards. Time lines. Basic Math.

Let's say you have a scene of head moving from profile to full face and rising it's left brown. So you have storyboard with the profile with an arrow showing in which direction it moves. Underneath this picture it's timestamped. Let's say 10'55. Next picture it's full frontal face with timestamp 10'53.
So a between those two frames we have 3 second. 12 frames a second give us 36 frames.

The animators create a crude drawings (photos/renders) of those 36 frames. Especially for deciding where to make smudges because smudges save a LOOOOOT of time.

To make things easier (and production more time and money consuming) each character on screen can have it's own animator that supervise it's movement on the timeline.

Next you have skeletons on which you build. Their joint often have "clicking" ability. So to have full arm motion from curled to straight it takes 15 clicks. 15 changes of position. Easier to count and connect defined position it should be in desired time.

And here where timeline goes into extra play. You have second divided on frames. In some of those frames you animator put extra info like "use hand number2" and 4 frames later "use hand number1". Like with mouth, to say "Lola" you need a certain amount of time. During which you open mouth in particular way. So you can transcribe mouth movement on a timeline and pinpoint certain shape to exact "frame" it should fall onto.

Look at some Aardman Studios making off's. They have full suitcase of Wallace mouth movement. Video and photos from Pirates as reference

In this case you would have pre-recorded speech which then you would transcribe, and attribute number (that is connected to sound) to certain start and duration time.

Answer 2

Experience. They were trained puppeteers and had lots and lots of practice. There really was no way to check the work before hand, even taking a polaroid of each "frame" might give you a sense of the motion, but it couldn't replicate the lighting, focus, and exact frame rate of the camera (since you would be flipping it by hand). This article mentions some recent innovations in stop motion and says:

There have been other digital advancements in capture techniques, too, including the use of digital SLR cameras to acquire each frame of animation. Prior to that, film cameras were used and that meant the resulting stop-motion animation could generally not be checked until the film was developed (imagine the hours of work that could have been lost to this process).

They could also storyboard out the action to make sure specific things were happening at the same time, like one character is looking at another while something happens behind them. I'm pretty sure I've seen "low frame rate" versions of scenes done quickly just to make sure it will look correct when they do it for real.