Vivitar Filters are manufactured from high-quality solid optical materials. Each individual filter is heat-treated to avoid any rare movement or distortion. Our UV filters remove and absorb ultra violet rays, giving sharper contrast to your digital images. The Vivitar Ultra Violet filters minimize the bluish cast sometimes found under daylight conditions. These filters will render your photos clearer, sharper and with more contrast. For those who enjoy outdoor photography, especially distant vistas, a UV filter can produce a more distinct image by removing much of the color aberration normally associated with atmospheric haze. They are also the best available protection against accidental damage to the front element of your lens. If you accidentally drop your lens, you will be protected against nicks and scratches. As a lens protector, it should be left on at all times. The number on the filter you need will depend on the thread size of your lens. For example, the kit lens which comes with the Canon Rebel XT is 58mm, so you would need a 58mm filter.