I will introduce test items and measuring methods for camera lenses in the “New Face Clinic” of the “Photography Journal, Asahi Camera” that is a monthly magazine for camera and photo enthusiasts. In that article, we introduce the lens configuration, special glass material, aspheric surfaces, coating type first. The main test items are focal length, open aperture value, spherical aberration, curvature of field, astigmatism, distortion, and modulation transfer function (MTF). Also, we actually shoot distant views, point light sources, close-up shots and evaluate images through the eyes. Although the test results are mixture of the effect of the image processing and physical lens performance, we measure Spatial Frequency Response (SFR). Finally, we evaluate the lenses comprehensively from these test results.
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