Sequential trials with new rare-earth intensifying screens.

Sequential analysis of idential radiographs with calcium tungstate (CaWO4) and rare-earth intensifying screens was performed in four test situations. Most preferences in the direction of rare-earth screens were due to motion unsharpness with CaWO4 screens. Better contrast was found with rare-earth screens in one test situation in spite of low kVp exposures. Assessment of the quality of the radiographs in practical situations gave results which differed to a certain extent from what might be expected from the technical assessment of the properties of the screens.