This 49mm Variable ND Lens Filter Plus+ from Urth provides an increase in neutral density through a range from 1 to 5-stops. Increasing neutral density offers finer control in available shutter speeds or aperture settings for both still and video applications. Using a longer shutter speed makes it possible to increase blur to convey a sense of movement, or to dial in a video camera frame rate. Increased density also makes it possible to shoot using wider lens apertures, helping to isolate a subject from the background. This level of image control can help to create more cinematic effects in low to bright light.
The filter is made from Schott B270 optical glass that features 20 layers of multicoating for reduced lens glare, providing a more consistent transmission curve and optimal light transmission. It also features nano coating on each optical surface that resists water, oil, dust, fingerprints, and scratches, making it ideal for use in harsh environments, and also easy to clean. The rotating aluminum filter ring has a density scale for repeatable results, and a slim design for use with wide-angles lenses without vignetting.