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Shutter angle to shutter speed calculator
Convert between shutter angle and shutter speed for any frame rate, see the motion-blur look you'll get, and avoid flicker under artificial light. Formula: shutter speed = angle ÷ (360 × fps) — so 180° at 24 fps is 1/48 s, and 172.8° at 24 fps is exactly 1/50 s.
Common shutter angles
| Angle | Speed @24fps | Look |
|---|---|---|
| 360° | 1/24 s | Max motion blur, dreamy |
| 180° | 1/48 s | Natural — the standard |
| 172.8° | 1/50 s | 180°-equivalent, flicker-safe at 50 Hz |
| 90° | 1/96 s | Crisp, slightly staccato |
| 45° | 1/192 s | Sharp, gritty (battle scenes) |
Shutter angle to shutter speed at every frame rate
The same angle gives a different shutter speed at each frame rate. Rounded to the nearest usable denominator; exact values in bold.
| Angle | 24 fps | 25 fps | 30 fps | 50 fps | 60 fps |
|---|---|---|---|---|---|
| 360° | 1/24 s | 1/25 s | 1/30 s | 1/50 s | 1/60 s |
| 180° | 1/48 s | 1/50 s | 1/60 s | 1/100 s | 1/120 s |
| 172.8° | 1/50 s | 1/52 s | 1/62.5 s | 1/104 s | 1/125 s |
| 144° | 1/60 s | 1/62.5 s | 1/75 s | 1/125 s | 1/150 s |
| 90° | 1/96 s | 1/100 s | 1/120 s | 1/200 s | 1/240 s |
| 45° | 1/192 s | 1/200 s | 1/240 s | 1/400 s | 1/480 s |
Shutter speed to shutter angle
Going the other way — you know the shutter speed and need the angle to dial in — the formula is angle = 360 × fps × shutter speed. At 24 fps, 1/50 s gives 360 × 24 ÷ 50 = 172.8°, and 1/60 s gives 144°. The table covers the speeds that come up on set, including the 23.976 fps that most "24p" cameras actually record.
| Shutter speed | 23.976 fps | 24 fps | 25 fps | 30 fps | Flicker-free at |
|---|---|---|---|---|---|
| 1/48 s | 179.8° | 180° | 187.5° | 225° | — |
| 1/50 s | 172.6° | 172.8° | 180° | 216° | 50 Hz |
| 1/60 s | 143.9° | 144° | 150° | 180° | 60 Hz |
| 1/100 s | 86.3° | 86.4° | 90° | 108° | 50 Hz |
| 1/120 s | 71.9° | 72° | 75° | 90° | 60 Hz |
"Flicker-free" means the exposure lasts a whole number of light pulses: lights on 50 Hz mains pulse 100 times a second and on 60 Hz mains 120 times, so 1/50 and 1/100 s are safe in Europe and 1/60 and 1/120 s in North America and Japan. The angle you need for that speed changes with the frame rate, which is the whole reason this conversion matters.
Read it the other way round to go from speed to angle: find the speed in the row for your frame rate and the angle is on the left. The calculator above does both directions for any value, including frame rates this table doesn't list (23.976, 29.97, 48, 120).
Flicker under artificial light
Lights pulse at twice the mains frequency. To avoid banding/flicker, use a shutter speed that's a whole multiple of the mains frequency:
| Mains | Flicker-safe speeds | Tip |
|---|---|---|
| 50 Hz (EU) | 1/50, 1/100 s | At 25 fps use 180°; at 24 fps use 172.8° |
| 60 Hz (US/JP) | 1/60, 1/120 s | At 30 fps use 180°; at 24 fps use 144° |
What is shutter angle?
It comes from rotary film shutters: a disc with an opening of N degrees spinning once per frame. A 180° opening exposes for half the frame. Digital cameras emulate it; many let you set angle or speed.
Higher fps for slow motion?
Keep the 180° rule for natural blur (e.g. 1/120 s at 60 fps). For sharper slow-mo with less blur, narrow the angle.
The 180° rule and when to break it
The conversions here encode a century of practice. At 24 fps with a 180° shutter you're exposing 1/48 s per frame — the motion blur audiences read as "cinema". Keep the angle and change the frame rate and the shutter speed follows: 1/50 at 25 fps, 1/120 at 60 fps, 1/240 at 120 fps for slow motion that stays crisp when conformed.
The practical trap is lighting flicker. Under 50 Hz mains (Europe), shooting 24 fps at 1/48 can beat against HMIs and cheap LEDs; the standard fixes are 1/50 s — equivalent to a 172.8° angle at 24 fps, which is why that oddly specific number is a menu preset on ARRI and RED bodies — or flicker-free fixtures. Under 60 Hz mains the safe speeds are 1/60 and 1/120.
Creative departures are deliberate: a 45–90° shutter gives the staccato, blur-free action popularized by Saving Private Ryan; 270–360° smears motion for dream sequences or to squeeze exposure out of low light. This converter translates any of those choices between angle and speed for whatever frame rate you're running.
What shutter speed equals a 180° angle?
Half the frame interval: 1/(2×fps). So 1/48 s at 24 fps, 1/50 at 25, 1/60 at 30, 1/120 at 60. That symmetry is the whole convenience of thinking in angles — the motion character stays constant across frame rates.
What shutter angle equals 1/50 s?
It depends on the frame rate: angle = 360 × fps × shutter speed. At 24 fps a 1/50 s shutter is 172.8°; at 25 fps it is 180°; at 30 fps it is 216°; at 50 fps it is 360°.
Why do cameras offer 172.8°?
Because 172.8° at 24 fps equals exactly 1/50 s, which synchronizes with 50 Hz mains lighting and kills flicker when shooting film rates in PAL countries. Its sibling is 144° at 24 fps under 60 Hz (1/60 s).
Does shutter angle affect exposure?
Directly — halving the angle costs one stop. Going from 180° to 90° loses a stop of light; 360° gains one at the price of doubled motion blur. That trade is why low-light shooters flirt with wide angles.
What is the shutter angle formula?
Shutter speed (in seconds) = angle ÷ (360 × fps), and the reverse, angle = 360 × fps × shutter speed. Example: 180° at 24 fps = 180 ÷ 8,640 = 1/48 s; 1/60 s at 24 fps = 360 × 24 ÷ 60 = 144°.
What shutter angle is 1/60 at 24 fps?
144°. It is the flicker-free setting for shooting 24 fps under 60 Hz mains lighting (North America, Japan), the counterpart of 172.8° under 50 Hz.