Does higher FPS mean less motion blur?

Hey there! Motion blur is a fascinating phenomenon that applies to both filmed footage and real-time rendered graphics like in video games. It occurs when objects move rapidly across the frame. This makes the object appear blurred or unclear in each individual frame.

By increasing frame rate – the number of frames captured or rendered per second – motion blur is dramatically reduced. This is because there are more "snapshots" of the moving object, so less overall movement is captured between each frame.

Let‘s dive deeper into the world of motion blur, and how higher frame rates can help eliminate this effect to create crisper, sharper footage!

What causes motion blur?

Motion blur happens because of the way cameras and our eyes work. They don‘t sample the world instantly like a still photo – they are continuously capturing light over a period of time.

So when something moves quickly, it is in a different position at the start of the exposure versus the end, making it appear blurred along the direction of motion. Slower shutter speeds cause more pronounced motion blur.

This is the same reason moving objects can look blurred to our eyes in real life. Our vision is essentially capturing continuous "video" rather than snapshots.

The 180 Degree Shutter Rule for Natural Motion Blur

In cinematography, there is a guideline called the "180 degree shutter rule" which gives the most natural and pleasing motion blur at standard film frame rates.

This rule states that the shutter speed should be double the frame rate. For example, at 24 frames per second, a shutter speed of 1/48 sec (24 x 2) provides the ideal amount of motion blur.

Why 180 degrees specifically? It has to do with the angle that the shutter is open relative to the full "360 degree" duration of a frame:

By maintaining a 180 degree shutter, the same amount of motion blur is retained when going from 24fps to 30fps or 60fps. This provides a consistent cinematic look.

Deviating from the 180 degree standard creates distinctly different motion blur effects:

• Smaller angles like 90° (1/500s at 60fps) reduce motion blur substantially for sharper, crisper footage.

• Larger angles like 270° (1/30s at 60fps) maximize motion blur, giving dream-like or ghosting effects.

Diminishing Returns: Why Framerates above 60fps Have Less Impact

So if higher frame rates mean less motion blur, why not go even higher than 60fps?

While increased FPS always reduces motion blur, there are diminishing returns past 60fps due to limits in human visual perception.

The average person can only resolve up to about 60 "frames per second" due to the refresh rate of our eyes. So while filming at 240fps and slowing down to 60fps playback gives buttery smooth slow motion, playing footage back at 120fps or 240fps won‘t look twice or four times sharper to our eyes.

That said, higher frame rates do continue to provide benefits:

• Reduced input lag for VR/AR and interactive applications
• Decreased chance of stuttering or tearing at fast motion
• Support for higher slow motion playback speeds

So while the improvements become marginal, higher FPS capabilities ensure you‘re taking full advantage of modern high refresh rate displays and powerful gaming PCs!

Motion Blur in Games: Realism vs. Responsiveness

Motion blur effects are commonly added to games especially in racing genres. This introduces cinematic, realistic blurring during fast motion similar to video footage.

However, many gamers strongly dislike motion blur! While more lifelike, it has some downsides for gaming:

• Can obscure and hide detail, making it harder to see
• Adds additional GPU load, lowering framerates
• Reduces responsiveness for competitive gaming

So motion blur typically needs to be an optional setting in games. Players seeking immersion and realism may enable it, while competitive esports players disable it for maximum visibility and responsiveness.

Finding the right balance comes down to the game‘s priorities and art style. Super realistic simulators typically demand full motion blur, while fast-paced shooters favor responsiveness.

Slow Motion Frame Rate Guidelines

To create smooth, artifacts-free slow motion, video needs to be recorded at a frame rate much higher than the playback frame rate.

As a general rule of thumb:

• 30fps playback requires 60fps, 120fps or 240fps capture
• 60fps playback requires 120fps, 240fps or 480fps capture

So doubling the recording frame rate versus playback is the minimum for decent slow motion results. Using an even higher capture rate (3-4x) allows slowing things down dramatically for ultra smooth hyperlapse effects!

Do High Refresh Rate Displays Reduce Motion Blur?

Displays with faster refresh rates like 120Hz or 144Hz can definitely help reduce the perception of motion blur when viewing high FPS content.

However, a high refresh rate monitor alone won‘t eliminate motion blur if the source material (game, video etc.) is lower frame rate like 24/30fps.

It‘s the combination of a high FPS source with a fast refreshing display that minimizes motion blur for the sharpest, clearest image quality during motion.

This is a key reason high refresh gaming monitors have become so popular. Playing a game rendered at 144 FPS on a 144Hz display virtually eliminates motion blur for ultra-responsive gameplay.

While 60Hz has been the standard for decades, we can expect even faster 240Hz, 360Hz or 480Hz monitors in the future!

Conclusion: The Need for Speed!

Well, we‘ve covered a TON of ground looking at motion blur, frame rates, shutter speeds, games, video, and everything in between!

The core point remains:

Higher frame rates directly translate to reduced motion blur.

While artistic motion blur absolutely still has its place for cinematic films and realistic games, fast FPS clearly allows sharper detail and responsiveness.

The 120fps slow motion modes we now see on phones are just the beginning – we will continue to see frame rates and refresh rates soar to new heights!

I hope this cleared up any lingering questions you had around motion blur and the advantages of higher FPS. Let me know if you have any other topics you‘d like me to cover related to cameras, displays or graphics technology!