Simulator for automatic photographic printing apparatus including inversion circuitry and spectral characteristic compensation

摘要

A simulator for use in an automatic photographic printing apparatus of the type in which a negative image carried by a color negative film is printed on a photographic paper by a light source system which is under an automatic exposure control, the simulator having a CRT for displaying a positive image corresponding to the negative image. The simulator includes an inversion circuit for inverting the output from an image pickup device for picking up the image of the negative image, thus enabling the positive image corresponding to the negative image to be obtained, a first conversion circuit connected to the input of the inversion circuit and adapted for effecting a compensation for any difference between the integrated density of the negative image relative to the spectral sensitivity of the image pickup device and the integrated density of the negative image relative to the spectral sensitivity of the photographic paper, and a second conversion circuit connected to the output of the inversion circuit and adapted for substantially equalizing first tristimulus values according to the emission spectral characteristics of the fluorescent substance on the CRT means and second tristimulus values according to dye absorption characteristics of the print. In consequence, a positive image which is the same as the image to be obtained by the print is automatically displayed on the CRT with a high degree of accuracy.