Our cutting edge research and alternative manufacturing methods deliver the most color neutral ND filter for the discerning landscape photographer. In the time that it took us to achieve the X4 ND's unparalleled color neutrality we also took our hand at redesigning the filter frame from the ground up.

Worlds Sharpest ND Filter. 100% Guaranteed
The X4 ND features SCHOTT Superwhite B270 optical glass, which is an ultra clear crown glass. It is produced by melting high purity raw materials and then made using the continuous draw process. The result is excellent transmission in the ultraviolet, visible and infrared spectrums and a high surface quality that accepts our state-of-the-art MRC and nanotec coatings exceptionally well.

MRC16
Our state-of-the-art multi-resistant coating (MRC) is an optical coating applied to both surfaces of the glass disk to reduce reflection and to increase surface durability. Our proprietary MRC coating is structurally harder than the glass itself and the reduced reflections improve the efficiency since less light is lost. The reduction of reflections also improves the contrast of the image by elimination of stray light. The real world result? Better contrast and color.

Weather-sealed
We specifically designed the X4 ND as a workhorse ND filter for field work, built to withstand extreme wind, salt water, dust and other abrasive conditions and elements.

Nano Coatings
The X4 ND incorporates our state-of-the-art nanotec Nano Coatings Technology, which beads water and other elements rather than absorbing and smearing.

25 Year Support
We stand behind each X4 ND filter with our 25 Year Ironclad Guarantee with US-based phone, email and live chat support.

How does poor quality MRC affect image quality?
Low light transmission and green flaring are common problems with uncoated glass. As MRC coatings are added to each side of the optical disk light transmission steadily increases with flaring steadily decreasing. In our lab tests light transmission apexes at about 16-layers of MRC and slowly decreasing in transmission at 18 and above. 8-layers of MRC are applied evenly to both sides of each optical disk resulting in MRC16.

Worlds Most Color Neutral ND Filter. 100% Guaranteed
Most of the neutral density filters on the market exhibit a strong blue or magenta cast. The higher the ND factor the more pronounced the color cast. To achieve the most color neutral ND performance we had to develop an alternative manufacturing method to the conventional oven process.

Transmission Curve
Spectrometers are optical instruments that can detect spectral lines and measure their wavelength or intensity. Spectrometers can also be used to test the efficiency of an optical filter in order to determine whether a filter has properly blocked or transmitted specific wavelengths. A perfectly flat transmission curve would yield a perfectly color neutral result. And while there is no such thing as a perfectly neutral ND filter (contrary to a filter manufacturers claim) the X4 ND is the most color neutral and has the flattest transmission curve of any ND filter, guaranteed. Neutral density filters manufactured using the traditional method also have strong transmission in the infrared wavelength starting at 700nm, whereas the X4 ND maintains a very well controlled and flat transmission all the way throughout the visible spectrum and into IR.

A breakthrough design with traction
During the period of time that it took us to achieve the best color profile performance we also redesigned the filter frame from ground up. Constructed of high quality brass CNC machined with our signature traction frame, the X4 ND is easier than ever to attach and remove securely, even with gloves on in cold conditions. We specifically designed the X4 ND be a workhorse ND filter for field work, built to withstand extreme wind, salt water, dust and other abrasive conditions and elements and we guarantee each X4 ND to perform with optimal clarity and color neutrality for 25 years even in the harshest of conditions.