High event rate gamma camera

An apparatus for use with a gamma camera to increase count rate without causing dead time or pile up, the apparatus including a first processor optimized for simplicity and minimum dead time but with moderate to poor spatial resolution for generally determining the impact point of a photon on a scintillation crystal and a second digital processor which uses the general position information from the first processor to identify a subset of PMT intensity signals for further processing to identify the precise impact point location.