Shutter angle explorer
Turn the disc to 45°, 90°, 180°, 270° or 360° (or set any angle you like) and choose a frame rate. You will see the exposure time and a single frame of a moving object.
Shutter angle and motion blur
open — light passes closed — film advances / sensor is read out
exposure time = (angle ÷ 360) × (1 ÷ fps)
How to use the tool
- Choose an angle with a button or fine-tune it with the slider (11.25° to 360°).
- Choose a frame rate. The exposure time is recalculated with the formula (angle ÷ 360) × (1 ÷ fps).
- The lower panel shows a single frame of an object that crosses the full width of the picture in one second. The streak is built up by adding together the object’s positions while the shutter is open.
Every control also works from the keyboard: Tab moves between groups, the arrow keys change the choice within a group. If reduced motion is switched on in your system, animations don’t start by themselves.
What it tells you
Why an angle and not a time
The angle describes exposure as a share of the frame duration. The same angle at different frame rates gives the same ‘character’ of motion. A time in seconds would have to be recalculated every time the frame rate changed.
360° and beyond
A mechanical rotary shutter needs a closed section while the film is advanced, so it can never reach 360°. The electronic shutter of a digital camera can expose for the whole frame duration. More than 360° is impossible at a given frame rate — a frame can’t be exposed for longer than it lasts.
| angle | time | ms |
|---|---|---|
| 45° | 1/200 s | 5 |
| 90° | 1/100 s | 10 |
| 180° | 1/50 s | 20 |
| 270° | 1/33.3 s | 30 |
| 360° | 1/25 s | 40 |
More in the articles
Sources
Last checked: . The tool runs entirely in your browser and sends nothing anywhere.