A receiver operator characteristic (ROC) experiment designed to evaluate the diagnostic performance of 512, 1024 and 2048 monitors as compared to conventional analog films viewed on a lightbox was conducted. Fifty radiographs, 25 with and 25 without a simulated solitary nodule placed on the lung fields of an anthropomorphic chest phantom were used. These images were interpreted by six radiologists under the following six conditions: 512 and 1024 line resolution both with and without interactive contrast enhancement, and 2048 line resolution with contrast enhancement, and analog film on a conventional lightbox. As determined by the area under the ROC curve, which was the measure of diagnostic accuracy the 512 and 1024 line monitors performed below the analog film, the 2048 line monitor proved to be a viable alternative to the analog film. © 1989 SPIE.