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Shutter angle
calculator.

Convert shutter angle and frame rate into shutter speed and exposure time — the 180° rule, or any angle you like. For keeping motion blur natural at any frame rate.

fps
°
Shutter speed
The exposure per frame
Exposure time
Frame interval
Motion blur vs 180°

180° is the natural-looking default. Narrower angles (90°, 45°) crisp up motion — think the landing sequences — while wider angles smear it.

Keep the camera math on set.

Set Math bundles shutter, exposure and fourteen more calculators, free. DOPro puts them under a real director's viewfinder with framelines and lens presets.

Questions

Shutter angle, answered.

How do you convert shutter angle to shutter speed?

Shutter speed in seconds is the angle divided by 360 × frame rate. At 24fps with a 180° shutter that's 180 / (360 × 24) = 1/48 s.

What is the 180-degree shutter rule?

A 180° shutter exposes for half the frame interval, which gives natural-looking motion blur. It's the standard starting point for narrative film and video.

What shutter speed is 180° at 25fps?

180° at 25fps is 1/50 s. At 30fps it's 1/60 s, and at 24fps it's 1/48 s.