This report describes an outline of the Digital test chart No. 7, which has been published in the last April from The Imaging Society of Japan. In addition to the specifications, the development concept, production methods and verifications of image qualities were explained. No. 7 includes four kinds of digital images aiming for viewing on monitors and a silver halide print. Color reproduction introducing appearance models, sharpness and graininess are taken into account in the image processing. An unsharp masking technique was employed to enhance sharpness without unacceptable graininess deterioration. A sine wave chart was used to obtain spatial frequency responses in the scanning process, while frequency spectra of pictorial images are used to calculate the responses for the low resolution printer. Average delta E in the entire printer gamut is as small as 1.7 and high responses of more than 90% in visually important frequencies below 3 cycle/mm were achieved without significant increase in graininess. Related information can be obtained from the following Web : http://www.isj-imaging.org/announce/test_chart/list_test_chart.html
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