I wanted to get a pic of some waterfalls using a long exposure so that the water would be blurry. To get a six second exposure like I used here, I had to put on a 10-stop neutral density filter to block out some light. ISO 100, f7.1, 6 sec. Here’s a version where I used a Photoshop plugin called Topaz Simplify (Buz Sim filter) on the background only …
Sans Topaz:
Original full-frame image: