July 2008 It is great to compare solargraphs with document photographs
Diego Lopez Calvin send me a document photograph of the view in front of the can he has fastened in Valonsadero, Soria, Spain. The exposure was from 17 February to 3 July 2008. Compare the solargraph to the panorama photographed by Diego.
For example an embroidery needle works very well. Pinhole Size Calculator can be found on the Net here: http://www.mrpinhole.com/
holesize.php Determing Pinhole Size and Exposure can be read: http://ca.geocities.com/