Breakthrough Photography has announced what it calls a Dark CPL filter, which combines an ND and CPL into one filter that the company says is the world’s sharpest and most colour neutral.

The new Dark CPL line comprises six items: Dark CPL, 100mm and 170mm X4 GND, X4 ND Square (100mm & 150mm) and a 100mm holder called the X100 Holder.

It’s the X4 GND and X4 ND Square filters that Breakthrough Photography claims are the world’s sharpest and most colour neutral filters.

Stacking ND and CPL filters produces vignetting at around 19mm on a full-frame sensor, the company says, but the new Dark CPL eliminates vignetting down to 16mm on full-frame sensors.

The Dark CPL comes in densities of 3, 6 and 10 stops, while the X4 GND comes in 2-stop Hard & Soft, 3-stop Hard & Soft and 3-stop Hard Reverse options.

The Dark CPL accommodates the following thread sizes: 46, 49, 52, 58, 62, 67, 72, 77, 82, 86, 95 and 105mm.

And the Dark CPL is compatible with the following camera and lens systems: Leica®, Carl Zeiss lenses, Schneider Xenon, Canon, Nikon, Sony, Fuji and others.

The Dark CPL and X4 GND filters are currently on Kickstarter until 3 June 2017.

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