Long exposure moving water photography - Crescent Beach at Sunset

To make a great looking long exposure shot of moving water, you must use the right shutter speed. If you use too long of a shutter duration, the water loses detail and looks like dense fog. If you choose a shutter duration that is too short, you won't get enough motion blur to give your viewer a sense of movement.

The shutter duration that achieves a good mix of detail and motion blur is determined by how fast the water is moving. If it is moving slowly, you will need a relatively slower shutter speed to show the movement. On the other hand, if the water is moving quickly you won't be able to leave the shutter open for very long before you lose too much detail in the water and it looks like you're photographing mist.

For this shot I took a few days ago, I did trial and error until I liked what I saw. A quarter-second turned out to be right for these relatively calm, slow-moving waves.