Dependence of magnification upon the camera-to-eye distance in the Zeiss fundus camera.

The magnification of the Zeiss type of fundus camera depends, except for the case of emmetropy, on the camera-to-eye distance. Its relative variation is equal to the product of the patient's ametropia and the difference in the camera-to-eye distance. Moreover, magnification is also affected by changing the diopter range scales on the camera.