Filters can be used to help with exposure, reduce glare, and add special effects to photographs. There are several common types of filters including neutral density filters which reduce the overall amount of light entering the lens, graduated neutral density filters which reduce light exposure in specific areas of the frame, and polarizing filters which cut glare and enhance color saturation. Black and white and colored filters can be used to emphasize or de-emphasize certain colors for creative effects. Specialty filters produce effects like starbursts, diffusion, vignetting, and unnatural colors.