Editing Normal lens (section)

== Perspective effects of short or long focal-length lenses ==
Lenses with longer or shorter [[focal length]]s produce an expanded or contracted field of view that appears to [[Perspective distortion (photography)|distort the perspective]] when viewed from a normal viewing distance.<ref>{{cite book
 | title = Creating World-Class Photography: How Any Photographer Can Create Technically Flawless Photographs
 | author = Ernst Wildi
 | publisher = Amherst Media, Inc
 | year = 2001
 | isbn = 978-1-58428-052-1
 | page = 44
 | url = https://books.google.com/books?id=kC6-vduaO3cC&pg=PA44
 }}</ref><ref name="stroebel">{{cite book
 | title = View camera technique
 | edition = 7th
 | author = Leslie D. Stroebel
 | publisher = Focal Press
 | year = 1999
 | isbn = 978-0-240-80345-6
 | pages = 135–140
 | url = https://books.google.com/books?id=71zxDuunAvMC&pg=PA135
 }}</ref> Lenses of shorter focal length are called ''[[wide-angle lens]]es'', while longer-focal-length lenses are referred to as [[long-focus lens]]es<ref>[https://books.google.com/books?id=sbdGeFem1zwC&dq=%22normal+lens%22+%22long+focus%22&pg=PA71 Bruce Warren, Photography, page 71]</ref> (with the most common of that type being the ''[[telephoto lens]]es''). Superimposing a wide-angle image print against the original scene would require holding it closer to the eye, while the telephoto image would need to be placed well into the depth of the photographed scene, or a tiny print to be held at arm's length, to match their perspectives.{{citation needed|date=April 2017}}

Such is the extent of distortions of perspective with these lenses that they may not be permitted as legal evidence.<ref>Hampton Dillinger (1997) 'Words Are Enough: The Troublesome Use of Photographs, Maps, and Other Images in Supreme Court Opinions'. In ''Harvard Law Review''  Vol. 110, No. 8 (Jun., 1997), pp. 1704-1753  The Harvard Law Review Association</ref>

The [[International Center of Photography|ICP]] ''Encyclopaedia of Photography'' notes that for legal purposes: <blockquote>"Judges will not admit a picture that seems to have been tampered with or that distorts any aspect of the scene [or does not render a normal perspective]...That is, the size relationships of objects in the photograph should be equivalent to what they actually are."<ref>International Center of Photography (1984). Encyclopedia of photography (1st ed). Crown Publishers, New York supra note 88, at p.208</ref></blockquote>