The 27mm HMC Ultraviolet UV(C) Haze Filter from Hoya is a wise initial investment. It helps protect your valuable investment from dust, moisture and scratches, which can lead to costly repairs.
The "C" on the filter ring designates Hoya's thinner design for this filter. The result is an average light transmission of over 97% giving sharp contrast and well balanced color. The heat-resistant tempered glass does not affect color balance while improving image quality and providing a stronger more resilient filter. HMC (Hoya Multi-Coated) filters are recommended for enhancing the performance of today's multi-coated digital lenses. The multi-coating minimizes reflection at the filter surfaces which reduces flare and ghosting. The result is better light transmission and a clearer image.
A UV filter not only minimizes the bluish cast sometimes found under daylight conditions, but is also the best available protection against accidental damage to the front element of your lens. A lens that accidentally gets dropped on its front element while hiking can potentially be saved by purchasing this item. Some people refer to it as "cheap insurance". As a lens protector, it should be left on at all times.
Aside from that more-than-significant benefit, UV filters render your photos clearer, sharper and more contrasty. For those who enjoy outdoor photography, especially distant vistas, a UV filter can produce a more distinct and acceptable image by removing much of the blue tint normally associated with atmospheric haze.