Abstract: An imaging method and device are described for improving the performance of a gamma camera by optimizing a figure of merit that depends upon cost, efficiency, and spatial resolution. In a modular gamma camera comprising a tiled array of gamma detector modules, the performance figure of merit can be optimized by sparsely placing gamma detector modules within the gamma camera, optimizing collimation, and providing means for detector and/or collimator motion. Sparse gamma cameras can be constructed as flat or curved panels, and elliptical or circular rings.