Sunlight, daylight, incandescent, fluorescent, and other artificial light sources all have color characteristics that vary significantly. Filters give you better images by adjusting for these light variations.
Film and video are rated for a particular color temperature such as that of daylight or tungsten light. Filters are used to correct differences in color temperature between the recording medium and the light source.
Using tungsten film in daylight will produce a bluish cast. The 85 Series will produce natural colors when shooting with tungsten film outdoors. For best results use the filter that most accurately matches your film type