The present disclosure describes an image rendering technique that provides a simulated light source positioned within a three dimensional (3D) data set for rendering two dimensional projection images of the 3D data set. The simulated light source may be positioned anywhere inside or outside the 3D data set, including within a region of interest. The simulated light source may be a multidirectional light source. A user may select a position of the simulated light source via a user interface. A user may select an in-plane position of the simulated light source and an image processor and/or volume renderer may automatically calculate a depth position to maintain a distance between the simulated light source and a surface of a region of interest in the 3D data set.