One of the best ways to shoot with a very long exposure in bright sunlight is to use an ND filter. This is how you get that silky smooth water effect when capturing seaside scenes–which many photographers love to do.. When you combine an ND filter with the lowest ISO and the narrowest aperture, you can shoot at a very long shutter speed: and that gives you the intended effect. ND filters can help you get that look when shooting in the middle of the day; and it’s what photographers have been using for years and years. More recently though, Variable ND filters have taken more of a presence due to their versatility for both video and photos along with the ability to dial in how many stops of light you want to cut out.
When using an ND filter, note that the viewfinder of your DSLR will become very dark and it may even affect autofocus performance. So you’ll be best off using it in Live View mode. For the best results, you should manually focus, and most likely out to infinity. Additionally, you’ll need a tripod and to set your camera to the delay shooting mode to prevent camera shake. And don’t forget to turn off image stabilization.
Photographer Gavin Hoey, has a tutorial on how to use an ND filter after the jump. For another big landscape tip check out using a graduated ND filter.