Rolling Shutter

What this is about

Most CMOS cameras roll their readout, and most of the time nobody notices. The offset shows when things move faster than the scan: propellers turn into boomerangs, whip pans skew architecture into parallelograms, photo flashes and muzzle flashes light only half the frame. Crews plan around it — car rigs, drone work and strobe-heavy scenes get cameras with fast readout or true global shutter, and VFX supervisors ask about readout speed before agreeing to motion-heavy plates, because unbending a rolled image in post is expensive.

A term only helps when everyone on set means the same thing by it — so what follows is how it is used, not a dictionary definition.

What runs differently here

In planning terms, that means:

• Readout speed is the real spec: a fast rolling shutter can be invisible where a slow one ruins the shot.
• Skew, wobble and partial flash exposure are the three classic symptoms to test for.
• High-end cine sensors roll too — they just roll fast enough that few subjects catch them.

With TillyGen

TillyGen's shot list marks strobe, vehicle and whip-pan shots, so the camera package can be checked against readout speed before rental.

Change one constraint and the consequences travel through the whole plan: affected shots are flagged, the call sheet is regenerated, and nobody keeps working from yesterday's version.