X-ray calibration of RAR 2490 film for application to laser plasma experiments

An x-ray sensitometric calibration of Kodak RAR 2490 film has been performed over the 0.28-8.04-keV range of photon energies. The characteristic curves (optical density D vs exposure H) are fit well over the entire range by a two-parameter, analytic function, loglo(1O(D) - 1) = A log(10)H + B. Solarization is found to occur at an exposure of 2 x 10(3) photons/(microm)(2) for 1.49-keV photons. Comparison with other films is made.