A weighted sum of a set of component filters is used to effectively apply different “composite” FIR filters to compensate for aberrations resulting from different opto-mechanical settings. The FIR filters are “composite” in the sense that they are a weighted sum of the set of component filters. In one approach, the aberrations vary as a function of the opto-mechanical setting, and the opto-mechanical setting is used to determine the weights of the different component filters.