Imaging with neutrons at macro-world scales (e.g., >10 μm) requires particular understanding of the non-diffracting or refracting interactions that these electrically neutral particles have with their environment. While image formation with neutrons shares some commonality with other radiation sources such as X-rays and gamma rays, neutrons provide complementary interaction mechanisms to these techniques that can uniquely probe materials and structure. Neutron sources are also historically fraught with issues regarding low source intensities, challenging beam configurations and resolution limitations that are all closely linked. In this chapter we will present a mathematical construct and methods compatible with the design and characterization of radiography systems for volumetric imaging. We begin with a review of neutron image formation, provide resolution analysis concepts and methods for both the design and the characterization of radiography systems, and conclude with a review and discussion of volumetric reconstruction techniques using analytic or iterative computed tomography algorithms.