The PKC-1500 lens (37mm)is precision ground from Hi-index optical glasses, and all surfaces are fully coated for optimum color contrast and maximum light transmission.By adding a telephoto auxiliary lens to the camera's master lens the focal length is extended by the power of the accessory lens (1.5x).This results in a magnification of the size of the image by a factor of 1 1/2 times. It makes distant objects appear closer and larger.