Abstract: Disclosed herein is a method for determining a drop size distribution within a spray and/or a homogeneity of this spray, the spray being formed on atomization of a coating material composition, which includes atomization of the coating material composition by means of an atomizer, the atomization producing a spray, optical capture of the drops of the spray formed, by a traversing optical measurement (2), and determination of at least one characteristic variable of the drop size distribution within the spray and/or of the homogeneity of the spray, on the basis of optical data obtained as per step (2). Also described herein are methods for compiling an electronic database and for screening coating material compositions when developing paint formulations, carried out on the basis of the method.