1. An apparatus, comprising: processing circuitry configured to obtain a plurality of projection datasets, wherein each projection dataset is obtained from a different detector type or different detector configuration; and reconstruct, from the plurality of projection datasets, a corresponding plurality of images using a combined image reconstruction, wherein the combined image reconstruction increases a spatial correlation among the corresponding plurality of images relative to a spatial correlation among a plurality of images that are reconstructed using an individual image reconstruction that individually reconstructs each of the plurality of images.