Hoya incorporated magic coatings in these HD (heavy-duty) filters that are resistant to scratches, dirt and finger prints. Any oil stain on the glass can be removed effortlessly, unlike other filters where stains just stick to the glass like glue. Hoya HD filter uses specially hardened glass (4 times the breaking strength in ANSI standardized testing) that is far more resistant to breakage than other optical glasses.
Hoya HD Digital UV filter absorbs the ultraviolet rays which often makes outdoor photographs hazy and indistinct. A multi-purpose, fine-weather filter for color as well as black and white films. This is the first filter that every photographer should ensure they own. UV filter should be constantly fitted to a lens to give improved clarity and color balance as well as offering protection to your lens.
