1. A computer-implemented method of processing images comprising: determining, for a first camera of a plurality of cameras, a first camera exposure value; determining, for a second camera of the plurality of cameras, a second camera exposure value, wherein the second camera exposure value is different from the first camera exposure value; communicating the first camera exposure value to the first camera; communicating the second camera exposure value to the second camera; obtaining a first image from the first camera; obtaining a second image from the second camera; determining an array of effective exposure values for a stitched image stitched from the first image and the second image, wherein an array of effective exposure values corresponds to an effective exposure that varies over pixels of the stitched image and is an at least approximately continuous function over pixels of the stitched image; determining a first spatially-varying gain for the first image, wherein the first spatially-varying gain is a function of the effective exposure divided by the first camera exposure value, wherein the first spatially-varying gain varies over pixels of the first image; determining a second spatially-varying gain for the second image, wherein the second spatially-varying gain is a function of the effective exposure divided by the second camera exposure value, wherein the second spatially-varying gain varies over pixels of the second image; generating a modified first image by applying the first spatially-varying gain to the first image, wherein applying comprises a pixel-by-pixel multiplication wherein for a given pixel, a value in the first image of the given pixel is multiplied by a value in the first spatially-varying gain for the given pixel; generating a modified second image by applying the second spatially-varying gain to the second image, wherein applying comprises a pixel-by-pixel multiplication wherein for a given pixel, a value in the second image of the given pixel is multiplied by a value in the second spatially-varying gain for the given pixel; and generating the stitched image from the first modified image and the second modified image.