Otis Spann, Cryin' Time Album Cover, 1970

Chicago's leading postwar blues pianist, Otis Spann, appears melancholic behind the glass in this shot that graced the cover of his 1970 album, Cryin' Time 
Spann was a full-time member of Muddy Waters' band from 1952 to 1968 before leaving to form his own group. He also did session work with Howlin' Wolf and Bo Diddley. In 1969 he appeared on Fleetwood Mac in Chicago/Blues Jam in Chicago, Vols. 1–2