1. A method for tomographic imaging, comprising: processing three-dimensional time-of-flight projection data to generate corresponding data in a designated format that allows for computationally-cheaper image reconstruction than the three-dimensional time-of-flight projection data; reconstructing one or more preliminary images from the processed data using a particular image reconstruction technique for one or more iterations; iteratively varying one or more imaging parameters every one or more iterations, wherein the one or more imaging parameters comprise the designated format, the image reconstruction technique and one or more image quality characteristics; reconstructing one or more intermediate images from the one or more preliminary images using the iteratively varying imaging parameters; and generating three-dimensional time-of-flight images having the one or more designated image quality characteristics using the one or more intermediate images and the iteratively varying imaging parameters.