If you’ve ever seen those waterfall photographs where it’s bright daylight but the water appears to be flowing smoothly as if the shutter speed is very slow, you’re probably looking at a photo taken with a neutral density filter over the lens. They basically darken the scene allowing for a longer shutter speed to be used when there is still bright sunlight. Graduated neutral density filters are also popular. GND filters darken part of a scene, e.g. a bright sky, allowing a more even illumination throughout the picture. Below are a few great examples of photos taken with neutral density filters, I hope you enjoy them.