With Hama's variable neutral density filters, you can take photographs with a longer shutter speed. The filter blocks light between 1 and 8 stops. This is also possible if you've already reached the camera's longest shutter speed. Because the neutral density filter allows less light to pass through the lens, you can choose a longer shutter speed to capture things like the movement of a waterfall. By turning the front ring, you determine the amount of light that the filter allows through. Use the filter at the darkest setting to open a scene during recording, and then turn it to a lighter degree to bring your subject slowly into view.