1. A method for filtering a sinogram data set (P) comprised of projection views acquired by a tomographic system, the steps of the method comprising: a) producing, using the sinogram data set, a map (N) indicating a noise-equivalent number of detected photons, the map having values that are a function of incident photons (N 0 ) and values in the sinogram data set; b) calculating a normally distributed data set (Q) from the values in the map (N) produced in step a); c) filtering values in the normally distributed data set (Q) using a bilateral filter; and d) converting the values in the data set (Q) filtered in step c) to produce a filtered sinogram data set (P′) suitable for producing an image using an image reconstruction process.