OBJECTIVES: To derive and test a method to predict Perceptibility Curves (PCs) for direct digital intraoral radiographic systems. METHODS: A test object was used to determine the performance of an average observer with respect to the threshold contrast and internal noise of the human visual system. These data were combined with system parameters to predict PCs mathematically. RESULTS: Data on the performance of an average observer could be defined to obtain values of the effective threshold contrast as a function of background gray level. This function combined with the gamma-value of the system predicted PCs that agreed well with PCs obtained in the conventional way. CONCLUSION: It is possible to predict PCs from a limited number of system parameters together with predetermined data on an average observer.
OBJECTIVES: To derive and test a method to predict Perceptibility Curves (PCs) for direct digital intraoral radiographic systems. METHODS: A test object was used to determine the performance of an average observer with respect to the threshold contrast and internal noise of the human visual system. These data were combined with system parameters to predict PCs mathematically. RESULTS: Data on the performance of an average observer could be defined to obtain values of the effective threshold contrast as a function of background gray level. This function combined with the gamma-value of the system predicted PCs that agreed well with PCs obtained in the conventional way. CONCLUSION: It is possible to predict PCs from a limited number of system parameters together with predetermined data on an average observer.