Kenko Tokina announced the newest addition to their line of professional photographic filters, the HD3. Designed for the most extreme of conditions, and 4x stronger than standard optical glass, this coating is 800% harder than the previous generations of Hoya quality.
It's no secret that Hoya prides itself on the durability of their filters. Their engineers have developed a new ultra-hard nano-coating formula in addition to a new process for applying layers of antireflective coating to the HD3 glass. This is what gives you the coating that makes these filters 800% harder and 5 x flatter than the optical coating of the previous filters they have released.
The HD3 comes in a UV and Circular Polarizer filter to give photographers the ability to capture high-quality images in extreme settings without loss of color balance, contrast, or clarity due to adverse environmental conditions. These filters are deigned to be light-weight, and the rugged design means no scratches, stains or damage to the front of your lens. The filters are set in a low-profile aluminum frame to house the glass which allows the filter to maintain perfect parallel alignment to the sensor plane for maximum sharpness and eliminates vignetting when used on an ultra-wide-angle lens. The sizes range from 37mm to 82 mm.
Specifically, the HD3 UV professional filter features a new 32-layer propriety coating system that reduces or eliminates reflections on the surface of the glass and yields a 99.7% light transmission rate. It's because of this 32 layer coating that you will not see an effect on the color balance, contrast, or clarity of your final image.
Finally, the antistatic top-layer is water repellent, stain and scratch resistant and cleans easily when smudges or fingerprints are introduced to the surface.