A class of imaging systems in which the imaging optics, the sensor array and the image processing are related by three parameters: W040 the amount of third order spherical aberration, U the undersampling factor defined as the ratio of the Nyquist frequency of the sensor array divided by the diffraction-limited frequency of the imaging optics, and N the number of rows in the FIR implementation of the image processing. In one aspect, W040 is between approximately 2 and 8 waves, U is between approximately 0.05 and 0.30, and N satisifies an equation that defines the acceptable range of N as a function solely of W040 and U.