The 0.4-1.8 Variable ND Filter - Mark II is a high quality variable neutral density filter providing a reduction of about 1.3 to 6 stops (ND1.3 to ND64). This variable Neutral Density filter creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed. The degree of density is easily controlled by rotating the front filter ring via the non-removable lever. Calibrated markings (12 reference points) make it easy for repeatable positions. The front filter ring has a larger diameter than the rear which is designed to avoid vignetting, even when using wide angle lenses. The latest Mark II versions feature the ability to rotate the filter without unscrewing it from the lens, assisting the orientation of the polarisation effect in Variable NDs. This is particularly useful when dealing with the polarisation effect of expansive skies in landscape photography for example. The SLR Magic Variable ND filters are the highest quality multi coated optical glass to ensure the best performance. Variable ND filters usually show striation patterns in the out-of-focus circles of confusion in the bokeh but the SLR Magic Variable ND filters are optimised to suppress such unwanted artefacts. Suitable for film or still photography use. Includes protective case and front lens cap. Specifications: Filter Type: Variable ND Density: 0.4 (1.3 Stops) to 1.8 (6 Stops) Shape: Circle Circular Size: 77 mm Front Accessory Thread / Bayonet: 86 mm Filter Material: Glass Coatings: Multi-Coating In the Box: - SLR Magic 77mm Self-Locking Variable Neutral Density 0.4 to 1.8 Filter (1.3 to 6 Stops) - Lens Cap - Plastic Case