1. A method for non-invasive observations of a fundus using an ophthalmoscope ( 100 ), the method comprising: illuminating a retinal region of an eye ( 52 ) by projecting an illumination pattern of illumination light onto the retinal region of the eye ( 52 ); at least one of detecting at least a portion of fluorescent light emitted from the retinal region of the eye ( 52 ) and detecting at least a portion of illumination light reflected from the retinal region of the eye ( 52 ), thereby capturing a series of images of the retinal region of the eye ( 52 ) at a plurality of different relative positions of the retinal region of the eye ( 52 ) with respect to the illumination pattern projected onto the retinal region of the eye ( 52 ), wherein between the capturing of at least two images of the series the relative position of the retinal region of the eye ( 52 ) with respect to the illumination pattern projected onto the retinal region of the eye ( 52 ) is shifted in a non-controlled manner; and processing the captured images to extract a sub-resolution image of the retinal region of the eye ( 52 ).