Create a Neutral Density Filter Long Exposure Effect Using Photoshop CC’s “Path Blur ” Filter.
A popular effect is take a sunset or sunrise picture with blurred, streaks of clouds while the foreground remains in sharp focus. This requires a long exposure of 10 seconds or more while the camera is on a tripod. Under the right weather conditions, the clouds are moved by the wind as the shutter stays open This can creates an dreamlike, surrealistic image.
Since there is a lot of light at sunrise or sunset, it is impossible to get properly exposed image without controlling the light. This is done with a Neutral Density filter that can hold back 9 or 10 stops of light such as the Hoya NDX100. These are very dark, and you must carefully compose and focus your scene before attaching the filter and making the exposure (since you can’t see through the viewfinder with these attached).
These images are typified by cloud movement. But because the wind can blow in different directions at different altitudes, you often see the clouds streaking in different directions in the same image. This has made this effect difficult to achieve in Photoshop until the addition of the Path Blur filter (added in Photoshop CC 2014). Watch this tutorial to see how to achieve the Long Exposure ND Effect.