The invention is a method for emission tomographic reconstruction from measurement data, the method comprising the steps of: obtaining the measurement data corresponding to activity of particle emissions of a volume from a tomographic imaging system, and performing at least one iteration step to obtain emission density data of particle emissions of the volume from the measurement data, wherein the at least one iteration step comprises a forward projection being a projection from the emission density data to the measurement data, and a back projection being a projection from the measurement data to the emission density data, and the at least one iteration step is carried out in a parallel hardware architecture, wherein both the forward projection and the back projection are of at least partially gathering type, and the measurement data is of binned type. The invention also relates to computer readable medium and a system for processing tomographic reconstruction from measurement data.
