Various embodiments are described herein for a radiation dosimetry apparatus and associated methods for measuring radiation dose. In some embodiments, the apparatus includes multiple scintillating elements for detecting amounts of radiation dose at multiple points within a detection region. Each of the scintillating elements generates light in response to radiation interacting within their volume. A light guide combines the light generated by all of the scintillating elements as well as radiation-induced contaminated optical energy and transmits the combined light to a spectral analysis setup. Multi or hyper-spectral calibration technique allows calculating the dose or dose rate at the positions of the different scintillating elements. The calibration technique isolates the light produced by a given scintillating element from the other scintillating elements as well as any other source of radiation-induced contaminating light.