(a) 



RED. 



YELLOW. 



BLUE. 



RED. 



YELLOW. 



BLUE. 



(d) 



Figure 24. Three color photographs showing characteristic image forms 

 of white light point sources at different distances, (a) (b) and (c) were taken 

 with a lens having approximately the same chromatic aberration and astigma- 

 tism as the eye. (d) (e) and (f) were taken with the sources at the same dis- 

 tances with a corrected lens. Magnification 28 diameters. 



