Uses of filters in photography

Filters in photography can be classified according to their use:

• Clear and ultraviolet
  
  
• Color correction, also called "color conversion" or "white balance correction"
  
  
• Color separation, also called Color Subtraction
  
  
• Contrast enhancement
  
  
• Infrared
  
  
• Neutral Density, including the Graduated ND filter and Solar filter
  
  
• Polarizing
  
  
• Special Effects of various kinds, including
  • Graduated color, called color grads
  • Cross screen and Star diffractors
  • Diffusion and contrast reduction
  • Sepia tone
  • Spot
  • Close-up or macro diopters, and split diopters or split focus