‘The camera doesn’t lie” (or “the camera never lies”) means that photographic evidence shows what something actually looks like. The old saying has been used since the beginning of photography and was used with some irony even then to people who couldn’t believe that was what they looked like. The modern use of Adobe Photoshop to edit graphic images makes the saying somewhat antiquated today.
 
Dion Boucicault’s popular play, The Octoroon (1859), contains the line “the apparatus can’t mistake.” “The camera cannot lie” has been cited in print since at least 1867, “the camera never lies” since 1872 and “the camera does not lie” since 1889. The saying has also been used regarding television and movie cameras.
 
 
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The Octoroon; or, Life in Louisiana
A play in four acts
By Dion Boucicault
1859
Pg. 19:
SCUDDER, R., DORA, L., GEORGE and PAUL discovered; Dora being photographed by Scudder, who is arranging photographic apparatus, George and Paul looking on at back.
Pg. 21:
Scud. The apparatus can’t mistake. When I travelled round with this machine, the homely folks used to sing out, “Hillo, mister, this ain’t like me!” “Ma’am,” says I, “the apparatus can’t mistake.” “But, mister, that ain’t my nose.” “Ma’am, your nose drawed it. The machine can’t err—you mistake your phiz but the apparatus don’t.” “But, Sir, it ain’t agreeable.” “No, ma’am, the truth seldom is.”
 
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March 1867, The Crescent Monthly, “The Portraits of Stonewall Jackson,” pg. 168, col. 1:
But the camera cannot lie, says the photographist. Perhaps not, but like the telegraph, the operator may.
   
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Going to Jericho; or, Sketches of travel in Spain and the East
By John Franklin Swift
New York, NY: A. Roman & Co.
1868
Pg. 317:
It would be interesting to know, for “the apparatus can’t lie.”
     
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Photographic Mosaics:
An Annual Record of Photographic Progress
Edited by Edward L. Wilson
Philadelphia, PA: Benerman & Wilson, Publishers
1872
Pg. 42:
PERSONAL PHOTOGRAPHY.
By G. FRANK E. PEARSALL.
(...)
It has been ironically said, “The camera never lies.” This, in part, may be true; but I have seen many results coming from the camera that were proof positive that something lied. It may have been the operator.
 
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September 1873, The Photographer’s Friend, pg. 143:
Behold what the camera, that never lies, has done for her!
 
9 May 1877, New-York (NY) Daily Tribune, pg. 2, col. 3:
Tadpole (to the class photographer): Look at this proof. Do you call that a good likeness? Why it makes me look like a baboon.
Photographer: My dear Sir, our camera never lies.
—[Harvard Lampoon.
 
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1 November 1889, The Marine Engineer, pp. 329-330:
This was because the camera does not lie, and shipowners do—at least, so said Mr. Plimsoll.
 
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31 May 1890, Judge, “Stevens and the Hawk-eye Camera in Africa” by Thomas Stevens, pg. 126, col. 2:
There is no doubt about it these days, however, for like George Washington, the camera never lies.
 
25 April 1892, New-York (NY) Daily Tribune, pg. 12, col. 2:
The amateur photographer who takes a ghastly picture of you and then blandly tells you that the camera never lies is a nuisance of the first water.
 
Chronicling America
6 October 1893, The Jewish South (Richmond, VA), pg. 1, col. 3:
All Photographs are bound to be likenesses. The camera never lies. Artistic taste is the secret of a “good likeness.” Try Davis 827 East Broad street and then draw your own conclusions.
 
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May 1895, The Wood-Worker, pg. 15, col. 2:
THE camera and improved methods of producing engravings direct from the photograph, enable our friends the machinery makers, dry-kiln builders and others to get up catalogues at once handsome and interesting. There is always the satisfaction of knowing, when one looks at productions of this kind, that they are true to nature, for the camera doesn’t lie, or at least not very much.
 
January 1931, Photo-Era Magazine, pg. 4, col. 1:
The Camera Lies
(...)  We are so accustomed to looking at ourselves in the mirror, and seeing our best profile, that occasionally we are quite shocked when a camera exposes a view to which we are not quite accustomed. The camera lies.
   
The truth of the matter is, however, that the camera doesn’t lie; it merely turns our conceit inward.
 
OCLC WorldCat record
The camera doesn’t lie : fox trot : neither do I : from Billy Rose’s “Aquacade” = La cámara no miento
Author: Eddy Duchin; Buddy Clark
Publisher: Camden, N.J. : Victor, [1937]
Edition/Format:  Music : 78 rpm : Dance forms : English
 
OCLC WorldCat record
The camera never lies : adventures of a TV journalist
Author: Dan Rather; Mickey Herskowitz
Publisher: New York : Morrow, 1977.
Edition/Format:  Book : English
 
OCLC WorldCat record
The camera never lies : a book of extraordinary and bizarre photographs
Author: Cyril Fletcher; Vic Giolitto
Publisher: Exeter, England : Webb & Bower, 1982.
Edition/Format:  Book : English
 
OCLC WorldCat record
FEATURES - Faking it - Nothing is further from the truth than the old saw, “The camera doesn’t lie”
Author: James Tallon
Publisher: [Los Angeles, Calif., etc., CBS Magazines, etc.]
Edition/Format:  Article : English
Publication: Popular photography. (August 2000): 60
Database: ArticleFirst