1. A computer-implemented method for designing a color filter module for use in a plenoptic XYZ imaging system that captures XYZ images of an object, the plenoptic XYZ imaging system comprising a primary imaging subsystem, a secondary imaging array and a sensor array, the sensor array capturing multiplexed images of the object, the color filter module positioned approximately in a conjugate plane to the sensor array to provide spectral filtering of the multiplexed images, the computer-implemented method comprising a computer system performing the steps of: receiving a model of an object to be imaged by the plenoptic XYZ imaging system; receiving a candidate design for the color filter module, the candidate design for the color filter module including a candidate spatial partition of filter cells within the color filter module, the filter cells implementing an X filter response, a Y filter response and a Z filter response; modeling operation of the plenoptic XYZ imaging system with the candidate color filter module; calculating variation of ΔE as a function of the modelled operation; and modifying the candidate spatial partition of filter cells based on the calculated variation of ΔE.