"It's funny, but from the 1890s and until the First World War, photographers prized lenses for their unsharpness: when artists found the lenses that gave them just the right degree and quality of unsharpness, they treasured them like jewels. This attitude survived until the 1940s among portrait photographers. The unsharpness of their lenses of choice was considered by many portraitists an indivisible part of their aesthetic signature." Mike Johnston on the taste for sharpness of portrait lenses.