foundations
Capture technique
Definition
Capture technique is the umbrella term for how a stop-motion production actually records its frame-by-frame movement: which family of physical change the camera photographs (a puppet's incremental pose, a replaced part, a live performer's incremental position, a moving rig) and which software and camera workflow turns that change into an exposed frame. It sits above the individual techniques -- puppet animation, replacement animation, pixilation, motion control -- as the production-level choice of how those techniques are actually shot.
Overview
Every stop-motion technique still resolves to the same physical act: change the subject slightly, expose one frame, repeat. What differs between productions is the capture layer around that act -- how the crew reviews a frame before committing it, how the camera itself moves (or doesn't), and how many frames a given change spans. Modern capture software makes that layer explicit rather than leaving it to the camera operator's memory: Dragonframe, the field's dominant capture application, splits the job into an animation workspace built around low-resolution, fast-refreshing video-assist images for posing and onion-skin comparison against the previous frame, and a separate cinematography workspace for the high-resolution exposures that actually make the final cut -- letting an animator work quickly frame-to-frame without waiting on a full-resolution capture each time.
The choice of exposure interval -- one photographed frame per drawn/posed change, or the same pose held across two frames of running time (on-twos; see [[on-twos]]) -- is itself a capture-technique decision, and productions do not always hold it fixed for an entire film. On Guillermo del Toro's Pinocchio (2022), cinematographer Frank Passingham has described switching specific shots from animating on twos to animating on ones during lateral camera-tracking moves at 4K resolution, because the coarser two-frame hold produced visible strobing once the camera itself was also moving through the frame -- a concrete case of the capture interval being tuned per shot rather than treated as a single studio-wide rule.
Camera movement is a second axis of capture technique, independent of exposure interval. A locked-off camera only has to solve exposure and puppet posing; a moving camera additionally needs the move itself to repeat exactly, frame after frame, over a shot that can run for days of shooting. Motion-control rigs -- rotators for arcing moves, computer-driven tracks for dolly moves, robotic arms for complex multi-axis moves (see [[dragonframe-arc-motion-control]]) -- record a move as a set of keyframed positions and then play it back in small increments between exposures, so the camera's path stays identical across the whole shot even as animators work at their own pace beneath it. On Pinocchio, three dedicated motion-control operators worked across 34 separate motion-control units on the production at once, which is the scale a mixed slate of locked-off and moving shots actually requires on a feature.
Two further capture families sit outside puppet-and-set photography entirely. Replacement animation (see [[replacement-animation]]) swaps a physical part -- most often a face -- between exposures instead of deforming a single puppet, which moves the technical burden from the camera to the fabrication pipeline that supplies the replacement inventory. Pixilation (see [[pixilation]]) applies the same one-exposure-per-change principle to a live human performer instead of an inanimate subject, incrementally repositioning them between frames rather than a puppet. Both remain stop motion by the definition that matters here -- change the subject, expose one frame, repeat -- even though neither involves a sculpted puppet on an animation table.
Workflow
- Decide the exposure interval per shot, not just per production: on-ones where camera movement or fast action would strobe on-twos, on-twos where the softer, more even motion suits the scene and the animator's workload benefits from the coarser interval.
- Confirm which subject family the shot uses -- a single posed puppet, a replacement-part inventory, pixilated live performers, or a mix within the same set -- since that choice determines the fabrication and on-set prep the capture session depends on.
- For a locked-off setup, capture through the animation workspace's low-resolution video-assist and onion-skin comparison against the prior frame, then commit the final high-resolution exposure once the pose is confirmed.
- For a moving-camera shot, build and test the motion-control move first -- confirm the rig repeats its path exactly across a test pass -- before animators begin posing beneath it, since the move itself does not change once the shot starts.