Historical clue formulations

• Camera obscura feature — 2007-10-20
• It admits very little light — 2007-02-23
• Tiny puncture — 2005-01-17
• A poster may have one — 2001-12-14
• It's hard to see through — 2001-10-25
• Tiny aperture — 2001-08-09
• Film flaw — 2001-05-19