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Minolta A1 Lens Field Sharpness Test

The following picture sequence was taken during an outdoor event in which I had a few minutes of waiting. All were taken in aperture priority mode, ISO 100, anti-shake on and normal sharpness and color settings. The file mode was JPEG-XTRA FINE. The focal length used was 50.7mm which is the equivalent to 200mm in 35mm format. A second photo sequence was taken using the 7.2mm focal length which is the equivalent to 28mm in 35mm format.

The whole photograph has been reduced from the original 2560x1920 size to 640x480 with DiMAGE Viewer with no sharpness or color changes made. This is the full-frame of the F5.0 crop. The cropped images are shown 1:1.

Reduced full-frame picture, Minolta A1, JPEG Xtra-Fine

This test sequence illustrates the falloff in resolution due to diffraction. F11, although usable, is definitely beyond the edge of maximum sharpness. What is gained in depth of field is typically lost in overall image sharpness. With my specific camera, F7.1, at the 200mm setting, is generally the limit of sharpness. Shorter focal lengths will have an even greater limitation.

The lens is remarkably sharp at nearly every aperture. This is a testament to the excellent design of the GT lens.