ARK II RGND8(0.9)
(Reduced exposure grade:  3 stops    Material: Reverse Graduated optical glass)

Athabasca  ARK II RGND8

Material:
German Schott optical glass
Coating:
Water repellent
Stain resistant
Scratch resistant
Nano coating
Double side anti-reflective film
Technology:
Low reflection and light reducing layer
Thickness:2mm
Installation methods: plug-in filter

Athabasca ARK RGND(Reverse GND filter),it is normally used for less light scenes like sunrise and sunset.
Athabasca ARK RGND filter uses German Schott optical glass, with multi-ultrathin noble metal coating, it has the advantage of low reflection, and low color deviation. Also it adopts double-layer water repellent coating, it is really water repellent, scratch and stain resistant.