Abstract: An apparatus and method for reducing the blurriness of tomographic (3D) images constructed from a gamma camera system with one or more VASH (variable-angle slant-hole) collimators. A conventional gamma camera with a VASH collimator exhibits a loss of spatial resolution from the fact that the gamma-ray is entering the detector element at an angle other than normal to the surface. This depth dependence of the spatial localization causes a blurring of the spatial resolution, which is dependent on the incident angle relative to the normal, on the thickness of the detector element and on the stopping length of the gamma-ray in the detector element material. The invention provides an apparatus and method for correcting the spatial location where the gamma ray is recorded to improve the spatial resolution of the system.