A single photograph invites speculation, a witness to time stilled. Photographs reflect a moment, transported to the present, and holds them for eyes not yet born.

• Garry Winogrand, edited by Leo Rubinfien et al - review
• Garry Winogrand's classic and unseen photographs - gallery
• Sport picture of the day: migration of the ironmen
• The Red Balloon: haunted by a ghost town
• Auguste Rodin by Gertrude Käsebier - picture of the day
• Photography: putting Saddam Hussein back in the frame - in pictures
• The Observer's 20 photographs of the week
• The extraordinary story of Erwin Blumenfeld
• Erwin Blumenfeld's iconic images