Kenko-Tokina has announced a variable neutral density (ND) filter that can be adjusted fro ND2.5 to ND1000. The Kenko NDX filter can darken the scene by anywhere from 1.3 to 10 EV. The filter allows the use of wide apertures while keeping the correct exposure within the shutter speed range of your camera, or of very long shutter times to emphasise motion. The company suggests its use for shooting video with shallow depth-of-field, for instance. Its variable nature allows the amount of filtration to be reduced for focusing, then increased to the desired amount, without having to remove the filter. The filters can vignette when used with lenses wider than 28mm equivalent and are available in 77mm and 82mm filter thread sizes.

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