This site celebrates the photographers who go the extra mile by having accurate diagrams, or even diagrams at all,...

This site celebrates the photographers who go the extra mile by having accurate diagrams, or even diagrams at all, in the background of porn movies that have blackboards. Surprisingly safe for work. Thank you to Lyxia for pointing it out.

http://blackboardsinporn.blogspot.com.au/
http://blackboardsinporn.blogspot.com.au/