Abstract: A digital image detection apparatus and method of use are disclosed. The apparatus may include an array of photon detectors, configured to receive photons reflected from a target scene and a plurality of first arrival differential (FAD) units, where each FAD units is configured to receive a first input from a first photon detector in the array and a second input from a second photon detector. Each FAD unit may include a set-reset (“SR”) latch, configured to receive the first input and the second input and to determine which of the first input and the second input arrives earlier in time, and a counter control unit, configured to receive an output from the SR latch and increment a differential count based on the output.