Shooting Shoot
Everything decided at the moment of recording: how much light the lens lets in, how long the sensor is exposed, how many frames per second and how the signal is written. These are the decisions that are hardest to fix in post-production.
- cameras
- lenses
- shutter
- shutter angle
- ISO
- exposure
- frame rate
- dynamic range
What this section answers
- What shutter speed should I use at 25 or 24 fps?
- Why do we control light with an ND filter in video rather than with the shutter?
- What does native ISO mean?
- Which frame rate should I choose for Slovakia and the rest of Europe, for cinema or for slow motion?
Articles and tools
Quick reference
| fps | frame duration | 180° shutter |
|---|---|---|
| 23.976 / 24 | 41.7 ms | 1/48 s (1/50 s in 50 Hz countries) |
| 25 | 40 ms | 1/50 s |
| 29.97 / 30 | 33.3 ms | 1/60 s |
| 50 | 20 ms | 1/100 s |
| 59.94 / 60 | 16.7 ms | 1/120 s |
| 120 | 8.3 ms | 1/240 s |
Formula: time = (angle ÷ 360) × (1 ÷ fps).
Terms
- Frame rate fps
- The number of separate images recorded or played back per second. It determines how smooth motion looks and how much time each frame covers. More
- Shutter speed
- How long the sensor is exposed to light for each frame, for example 1/50 s. A longer time = more light and more motion blur. More
- Shutter angle
- Shutter speed expressed as a share of the frame duration. It comes from the rotating sector shutter of film cameras: time = (angle / 360) × (1 / fps). More
- ISO exposure index
- On digital cameras, a setting for the gain and mapping of the signal, not a physical ‘sensitivity’ of the sensor. Higher ISO brightens the picture but does not add light. More
- Native ISO base ISO
- The ISO value at which the manufacturer states the best balance of dynamic range and noise. Some cameras have two (dual native ISO).
- Aperture f-stop
- The ratio of the focal length to the diameter of the entrance pupil. Each full stop (f/2.8 → f/4) halves the amount of light. It also affects depth of field.
- T-stop
- An f-number corrected for the lens’s actual light transmission. Cine lenses are marked in T-stops so they can be swapped without changing exposure.
- ND filter neutral density filter
- A grey filter that cuts light evenly without changing its colour. It lets you keep your chosen shutter speed and aperture even in bright sunshine.
- Dynamic range
- The span between the darkest and the brightest tones a camera records with usable detail. It is given in stops (EV).
- Rolling shutter
- The sensor reads out its rows one after another rather than all at once. With fast movement, vertical lines lean (the ‘jello’ effect). The opposite is a global shutter.
In preparation
Topics we are working on. They are not published yet — we would rather have fewer pages, but verified ones.
- Sensor sizes and crop factor
- Lenses: focal length, angle of view, cine vs. stills lenses
- Dynamic range and how manufacturers measure it
- RAW video: what it is and what it isn’t
- Focusing: manual, autofocus, follow focus