Patent ID: 8427573

Claim:
A method for focusing a film scanner, the method comprising: converting image information of a film image to be scanned into electrical signals in a scanning unit of the film scanner, the electrical signals representing the scanned film image, and the scanning unit being assigned an optical unit of variable focus; displaying the electrical signals of the scanned film image on a monitoring screen; selecting a plurality of subareas of the film image to be scanned for the purpose of focus control, each of the selected subareas are separated from each other selected subarea; dividing the monitoring screen into a plurality of separate display areas corresponding to each of the selected subareas that are separated from each other selected subarea; simultaneously displaying the image information for each of the selected subareas that are separated from each other selected subarea of the film image to be scanned on an enlarged scale in the separate display areas of the monitoring screen; focusing at least a first one of the selected subareas by changing the focusing of the optical unit while simultaneously monitoring a variation in the focusing of the other selected subareas, wherein focusing is determined based on a structure of a film grain; and evaluating the frequency and amplitude information of the electrical signal for each of the selected subareas while changing the focusing of the optical unit, wherein the changing of the focusing is terminated when the sum of the amplitude information of the electric signals of the selected subareas reaches a maximum for high frequencies.