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.
One other important bit of information is the fact that the NDX filter does not change colour when you dial in the ND this will make this ND filter a very useful tool in your DSLR/large sensor video camera kit.
One of my contributors has told me that we are looking at €500 Euros for the 77mm version which works out at around £435, I really find it so insulting that manufacturers of filters charge the same price as a Nikon 70-200 VR lens, in my opinion they are cashing in on the DSLR craze, they will also find a reluctance of retail outlets willing to stock what is effectively two bits of polarised glass stuck together. In photographic terms we have had polarised filters for years and the technology is not a million miles away…SO WHY THE PRICE HIKE !
Not to worry Tiffen are also bringing out a variable ND filter at the more reasonable price of £199, and Tiffen have a far better reputation in the movie industry for their excellent glass.