Motion Blur Masterclass For Compositors

🔒 A deep dive into how motion blur works, the way cameras operate in the real world, and advanced techniques for dealing with motion blur in Nuke…

The Importance Of Motion Blur

Motion blur has a major impact on photography.

It can drastically change the look and feel of both still photos and movies. By influencing the motion blur, you can change a shot from looking dreamy and soft, to hyper-realistic, staccato, or even frozen-in-time.

A specific amount of motion blur is also associated with the cinematic look of movies. Getting the motion blur wrong can actually pull the audience out of their state of suspended disbelief.

So it’s important for compositors to know how to correctly work with motion blur.

As we will explore further in this tutorial, motion blur is heavily affected by one of the three pillars of photography: the shutter speed. And the shutter speed has to be in harmony with the other two pillars, aperture and ISO (as well as the lighting on set), in order to get a balanced exposure. Motion blur is therefore intrinsically linked to depth of field and image noise.

Because it determines the available shutter speeds, the capture frame rate is another element that affects motion blur. And going further down the rabbit hole, there are more factors influencing motion blur as well, which we’ll look into.

It can be a fairly complicated subject, but it’s very much worth getting a better understanding of motion blur in order to produce more natural looking imagery (or to bend reality, if you so choose).

Let’s break it all down in a simple but thorough way, starting by analysing what motion blur is and how it’s linked to the way cameras work. Then, we'll delve deeper into advanced techniques for working with motion blur when compositing in Nuke.

Motion Blur And Cameras

To understand motion blur, we first have to understand how cameras capture reality.