• Color blindness
    		•  one or more cone types absent or anomalous
  • Stationary night blindness

    •      		 poor rod sensitivity, slow adaptation, etc.;
    little or no rod degeneration
  • Macular degeneration
    		•  rods and cones only in macula degenerate
  • Cone degeneration 
    		•  cones degenerate, rods function well
  • Achromatopsia


    •  

    		 no cone function, rods function well
    congenitally dysfunctional cones
    end stage of cone degeneration
  • Retinitis pigmentosa
    		•  rods and cones degenerate
  • Cone-rod degeneration 
    		•  cones degenerate more quickly than rods
  • Congenital amaurosis
    		•  rods and cones fail at or soon after birth