Patent ID: 6320607
Filing Date: 2001-11-20
Classification: G02B

Abstract:
An electronic still camera comprising:an optical system including an image pickup lens, for focusing an image on a predetermined image-focusing plane;a solid-state image pickup element provided on the predetermined image-focusing plane and photoelectrically converting the focused image so as to generate image signals; andan A/D converter for converting the image signals into digital image signals;wherein (1) an image I1 is obtained in such a manner that a subject image is focused by the optical system on the solid-state image pickup element so as to obtain first digital image signals and the image I1 is formed on a sheet by an outputting means based on the first digital image signals, (2) an image I2 is obtained in such a manner that the same subject image is focused by the optical system on a silver halide photographic material provided on the image-focusing plane in place of the solid-state image pickup element, the silver halide photographic material is developed so as to obtain a visual image, the visual image is read by an image reading means so as to generate second digital image signals and the image I2 is formed on a sheet by the outputting means based on the second digital image signals, (3) the image I1 and I2 are obtained on plural sheets N respectively for each of plural different subject images M, (4) the images I1 and I2 are evaluated in terms of contrast and sharpness, in the case that the image I1 shows higher contrast and higher sharpness than the image I2, an evaluation value is 1, and in the case that the image I2 shows higher contrast and higher sharpness than the image I2, an evaluation value is 0, the total evaluation value X is obtained by summing up the evaluation values of the plural sheets N of the plural different subject images M, andwherein the optical system satisfies the condition ofX.gtoreq.M.times.N.times.0.8.