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Track 3 · Which camera2 min read

LESSON 12

Stills or cinema body

A cinema camera is built for hours of moving pictures, not single frames. The differences sit in the sensor, the files and the shutter.

SHUTTER ANGLE · THE SHARE OF EACH FRAME EXPOSED

Four discs with an open sector of 360, 180, 90 and 45 degrees; at 24 frames a second they expose each frame for 1/24, 1/48, 1/96 and 1/192 of a second.

What a cinema camera is for

A digital movie camera records footage to files instead of film, and since the 2000s such cameras have been the main tools of the film industry. The high-end ones offer large sensors, a choice of frame rates, recording with little or no compression, and room for high-quality lenses; some are only rented, never sold.

Shutter angle

Film crews describe the shutter as an angle, from the spinning disc shutters of film cameras. The angle is the share of each frame's time the sensor is exposed: 180 degrees is half, which at 24 frames a second is 1/48 s and gives the motion blur we think of as normal.

Log and grading

Many video cameras can record a log profile: a flat, washed-out image that keeps highlight and shadow detail a normal profile would clip. It needs colour grading afterwards, which is the point: the look is decided in the edit.

Rolling shutter

Many sensors read the frame line by line rather than all at once, so fast pans and spinning blades can lean or bend. A global shutter captures the whole frame at the same instant.

Try it today

  1. 01Set your camera to 24 or 25 frames a second.
  2. 02Set the shutter to 1/50 s and film a hand waving.
  3. 03Film it again at 1/500 s.
  4. 04Play both: one blurs like cinema, the other stutters.
  5. 05Pan quickly past an upright and look for leaning lines.

Figures from Wikipedia, 'Digital movie camera', 'Rotary disc shutter', 'Log profile' and 'Rolling shutter', read 2026.10.16. The times under the discs are worked out from the article's formula: exposure time = angle ÷ 360 × 1/24 s. The steps under Try it today are working practice, not a standard.