A digital booster for an optical system includes an image acquisition unit. The image acquisition unit is configured to acquire an image frame from a non-magnified optic. The image frame includes an aiming reticle imposed by the non-magnified optic. The digital booster includes a display and a processor. The processor is configured to locate the aiming reticle on the image frame, select a sub-frame of the image frame with an aspect ratio that is centered on the aiming reticle of the image frame, perform image inversion and rescaling of the sub-frame, and transmit the sub-frame to the display.