Camera lens filters are transparent or translucent glass or gelatin elements that attach to the front of a lens. They protect the camera lens, alter the characteristics of light passing through the lens or add special effects and colors to an image. There are different types of camera lens filters such as UV/Clear/Haze filters, circular polarizers, neutral density and color filters.
UV/Skylight filters are used to block UV rays (including UV haze and UV light) from hitting the film in cameras3. Circular polarizing filters are used primarily to darken skies that are much brighter than the foreground. Neutral density filters help to control the light that hits the sensor, subtracting light according to the opacity of the filter4. Graduated neutral density filters are used when there is a large difference between the brightness of the sky and foreground. Color filters are used to add color effects to an image. Close-up filters are used for macro photography. Special effects filters are used for creative purposes such as starburst effects or softening images.