Abstract: A gamma camera having a Compton scattered radiation deemphasizer. A summing device produces pulses proportional to the total energy of each scintillation caused by absorption of gamma photons in a scintillation crystal. Scintillation events are displayed at the x,y coordinates of the event on a cathode ray tube screen by unblanking the tube with z pulses applied to its control electrode. The deemphasizer determines where the peaks of total energy pulses fall in a part of the energy spectrum or window and between lower and upper limits. The deemphasizer causes small z pulses to be produced in the part of the spectrum where Compton scatter is most prevalent and causes increasingly larger z pulses as total energy increases to the midpoint of the spectrum where Compton scatter is insignificant. Constant amplitude z pulses are produced at and after the midpoint.