Dimmer can bring more exposure means for your creation, turn day into night and give full play to your creative space; In many cases, due to the external light intensity, we can't get a long enough shutter time, so we can't realize our photography intention. For example, when shooting water flow in the field, we want to use a 1-second shutter to make the water flow show a cotton like soft texture. However, due to the strong light, that is, shooting with the minimum aperture and minimum ISO of the camera, the shutter speed is still about 1 / 30 second. At this time, the only way is to use one or even two nd8 lenses to reduce the light entering the lens. There is a simple formula. Assuming that the shutter speed of normal exposure of your camera is t without adding a dimmer
