Purkinje's shift:
a. refers to the transition of retinal sensitivity between photopic and scotopic vision
b. refers to the shift in the spectral sensitivity of the human retina toward shorter wavelengths of light
c. accounts for blue colour appearing brighter at dusk
d. all above
a. refers to the transition of retinal sensitivity between photopic and scotopic vision
b. refers to the shift in the spectral sensitivity of the human retina toward shorter wavelengths of light
c. accounts for blue colour appearing brighter at dusk
d. all above