About: http://webisa.webdatacommons.org/260737151

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	I thought an aperture was a mechanical opening (a small hole) and small holes (as well as slits, like we used in physics class) creat diffraction.I though a F-stop depends on the size of the aperture and the focal length.
http://www.w3.org/ns/prov#wasQuotedFrom	wetpixel.com