About: http://webisa.webdatacommons.org/198567967

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	Each full f-stop either doubles or halves the light passing through a lens depending on whether your opening the aperture or stopping down.
http://www.w3.org/ns/prov#wasQuotedFrom	dpreview.com