Techniques for precise recording of gray-scale images from computerized scintigraphic displays.

Accurate, reproducible recording of gray-scale images from a computer requires careful calibration and control of the factors that affect photographic exposure. These include exposure time, CRT brightness and contrast, film type, and photographic processing. A method is described for calibrating the imaging system; it accounts for nonlinear CRT phosphor and film response and permits the recording of any desired gray scale. The key to this technique is a graphical method for correlating the measured film response with the desired gray scale in order to develop a translation table that will in turn produce the desired gray scale on film. The technique is applicable to any computerized nuclear medicine display system.