Quantitative Calibration of X-ray Film Response in the 5-keV to 13-MeV Region

Abstract

Response vs energy was measured for Kodak No-Screen and Rapid-Process films. Monochromatic incident radiation was obtained by fluorescent excitation of the characteristic x-ray lines in an element such as copper followed by crystal diffraction to pass only the Kα component. Fluorescing elements from atomic number 23(V) to 60(Nd) covered the energy range 4.95–37.0 keV. A single point at 1.25 MeV was obtained for gamma radiation from ⁶⁰Co. A proportional detector measured the incident flux density (photons cm⁻² sec⁻¹). The No-Screen film is more sensitive than Rapid-Process film and has greater contrast. At 8 keV, to obtain a photographic density of unity requires 3.76 × 10⁷ photons/cm² for No-Screen film and 4.19 × 10⁷ photons/cm² for Rapid-Process film; at 20 keV, No-Screen film requires 7.47 × 10⁷ photons/cm² and Rapid-Process film requires 12.87 × 10⁷ photons/cm².