B+W F-Pro Multicoated UV Filter
This B+W MrC UV Filter blocks the invisible UV component of light from the sky, which can cause blur and to which many color films react with a blue cast. These filters should be called UV-Blocking Filters, because there are filters for technical applications that pass UV radiation and block all the other wavelengths. Nevertheless, the short term “UV Filter” has become established among photographers. B+W UV Filters are ideal for photography in high altitudes (in the mountains), by the sea and in regions with very clean air. The pictures gain brilliance and disturbing blue casts are avoided. Because the Schott glass is colorless, color rendition is not altered, aside from the elimination of the unwanted blue cast, and no increase in exposure is required. That makes a B+W UV Filter very suitable as protection of the front element of the taking lens against dust, flying sand, sea water spray and the like, and it can be kept on the lens at all times. It is recommended for analog color and black-and-white as well as digital photography.
The MRC (Multi-Resistant Coating) by B+W is not only an extraordinarily effective multiple layer coating, it is also harder than glass, so that it protects filters from scratches (for instance when cleaning the filters), and it is also water and dirt repellent, thus facilitating filter maintenance.

HOYA Digital Circular Polarizer
Color and contrast enhancement
Light rays which are reflected by any surface can become polarised so Hoya polarising filters are used to select which light rays enter your camera lens. Hoya Pro 1 Digital CIRCULAR PL filters allow you to remove unwanted reflections from non-metallic surfaces such as water, glass etc. They also enable colors to become more saturated and appear clearer with better contrast. This effect is often used to increase the contrast and saturation in blue skies and white clouds. HOYA's Pro 1 polarising filters do not affect the overall color balance of a shot

Hoya DMC PRO1 Digital Filters are specifically designed and engineered for Digital SLR Cameras. The Digital Multi Coated (DMC) Hoya filter glass greatly reduces lens flare and ghosting. The Pro 1 Black Almite Frame (BAF) has a black matte finish that reduces reflections. In addition, the Black Rimmed Glass (BRG) reduces light reflection around the filter edge. The Pro 1 Low Profile Frame (LPF) is an Ultra thin frame which helps avoid vignetting on wide-angle lenses. The Digital Pro 1's Knurled Edge Frame (KEF) aids easy attachment and removal.