The present invention relates to a method and a system for determining the positions of a plurality of objects in a digital image by discriminating true positive positions of the plurality of objects from false positive candidate positions of the plurality of objects. In particular, the invention relates to a method for determining the positions of a plurality of objects in a digital image by discriminating true positive positions of the plurality of objects from false positive candidate positions of the plurality of objects, the plurality of objects being configured to receive molecules comprising genetic information.