An optical system for digital microscopy having at least one lens, at least one telescope of the Kepler type and tube optics, wherein an aperture is arranged between the telescope and the tube optics, which aperture is imaged by means of the telescope at the rear focal point of the lens and the following conditions are met simultaneously: A light conductance value (L) of the lens is ≧1.4, A light conductance value (L) of the telescope is ≧0.35, A light conductance value (L) of the tube optics is ≧0.35, wherein the equation for the light conductance value (L) is L=A(tan ξ,) where A is the pupil diameter and ξ is the angle of gradient of the pencil of light rays in infinite space, and wherein the microscope magnification (Γ) of the telescope is in the range −⅓≦Γ≦−3.