1. A method, comprising: obtaining, by a computing device, a radiance image comprising a plurality of separate microimages of an image of a scene, the radiance image having a spatial resolution that is a function of a resolution of said microimages and an amount of overlap in rendering of said microimages; displaying first and second portions of a user interface, the first portion comprising the radiance image, the second portion comprising a control area including multiple user interface elements that are user-selectable to adjust respective parameters of the radiance image; applying, by the computing device, a calibration technique to the radiance image to generate a transformation matrix for the radiance image without modifying the radiance image, the calibration technique being based on an adjusted value of one or more of the multiple user interface elements; and performing, by the computing device, a radiance processing technique on the radiance image to render an output image, at least a portion of the radiance processing technique being performed by a fragment shades on one or more graphics processing units (GPUs), the radiance processing technique including at least: applying the transformation matrix to the radiance image to transform the plurality of separate microimages according to the transformation matrix before texture look-ups in the fragment shader; and rendering the output image from the transformed microimages.