1. A photosensor-based radiation detection system, comprising: a detector having a plurality of photosensors therein, each photosensor being connected to analog-to-digital (ADC) circuitry, the ADC circuitry digitizing analog signals output by the photosensors to generate corresponding digital signals; and a processing unit configured to determine an arrival time and an amplitude of each of the digital signals by fitting the digital signals to a prototype waveform, the fitting including applying a weighting function that assigns varying importance to different times within the prototype waveform, with a leading edge of the digital signals being most heavily weighted, wherein the prototype waveform and weighting function are determined by a generation procedure that includes parameterizing an initial prototype waveform and an initial weighting function, and optimizing the parameters via a calibration process.