PRO ADVICE HOW SHUTTER SPEED AFFECTS MOTION

Do you freeze it or let it flow?

It’s a decision that changes the appearance of a moving subject, such as water, considerably.

To the naked eye, water isn’t a diffused blur, but if you want to have a strong contrast between soft and sharp areas in the frame the camera can record it this way.

A fast shutter speed, such as 1/250 sec, will effectively freeze the movement of flowing water. But slow that shutter speed down by narrowing the aperture or adding an ND filter (or both), and you’ll see that shutter speeds from 1/30 sec and slower will have a dramatic effect on the water’s appearance. The slower you go, the softer and more ethereal the water will appear.

Often, a balance between blur and some water definition is best, but the only way to find out what works is trial and error on the day, as the speed of the water itself makes a difference.

The impact of shutter speed choices

There’s no doubt the two shutter speeds used on this mountain stream give very different results. The frozen water at the top doesn’t create the same differentiation between the stream and the land that the lower image, taken at the much slower shutter speed, does.