🎬 Frame Rate & Shutter Angle Calculator

Calculate the ideal shutter speed for any frame rate using the 180° shutter angle rule. Essential for natural motion blur and the cinema look.

Frame rate (fps)

Shutter angle (°)

Slow-motion playback fps

180° Rule Reference Table

Shutter Angle Looks

🎬 180° — Cinematic

The gold standard. Used in virtually all cinema and high-end video. Natural motion blur. The look audiences associate with "film."

✨ 90° — Sharp / Gritty

Reduced motion blur. Crisper look. Used in action films for heightened realism (Saving Private Ryan's battle scenes). Strobe-like effect at extremes.

💫 270° — Dreamy

More motion blur than standard. Used for dreamlike sequences, montages, or to suggest altered states. Slow-moving subjects look soft and atmospheric.

⚡ 45° — Stroboscopic

Very sharp, almost freeze-frame motion. Classic "war film" look made famous by Spielberg. Unsettling, hyper-real. Eyes tire quickly.

📺 1/50 or 1/60 — "Video look"

Fixed shutter speeds matching power line frequency prevent flicker from artificial lighting. Standard for news and broadcast. Higher shutter = video look even at 24fps.

🌅 Long exposure / ND filters

For very slow shutter speeds (smooth water, light trails), use a neutral density filter to reduce exposure without changing shutter angle. ND 3, 6, or 10 stops.

🎬 The 180° rule explained: On a film camera, the shutter is a rotating disc. 180° means the shutter is open for exactly half of each frame's duration (1/2 of 1/fps = 1/(fps×2)). At 24fps, shutter open for 1/48s ≈ use 1/50s. This creates the motion blur that makes video look "filmic."

💡 Artificial lighting flicker: In countries with 50Hz mains (Europe, Asia, Australia) use shutter speeds that are multiples of 1/50 (1/50, 1/100, 1/200). In 60Hz countries (USA, Japan, Canada) use 1/60, 1/120, 1/240. Breaking this rule under fluorescent/LED lights causes banding in footage.