An example macro stereo shot – courtesy of Stan White
Toronto. This photo and the accompanying article cover a trio of photo categories. Macro stereo shots; medical photos; and workplace photos. Added to this, the challenge of stereo macros means customized gear.
In issue 15-3 the late Stan White describes just such a challenge to create slides for use by a professor of oral surgery at the U of T.
Stan recounts his work in a lengthy, well illustrated article saying in part, “The problems of making close-up stereo images have long been known . The third dimensional effect is primarily the result of stereopsis – the fusing of two slightly dissimilar images into one cyclopean image. Conventional stereo cameras have their lenses spaced at 70mm about the spacing of the human eyes.
“This is fine for subjects at seven feet and beyond. Such a viewpoint separation when used close-up produces images so dissimilar that they cannot be comfortably fused. The human eyes suffer the same problem; try looking at the end of your nose sometime. The solution would have to come through hypostereo; the reduction of the stereo viewpoints to less than the human eye and for this application the stereo base would have to be about 4mm.
“A number of stereo close-up systems were developed during the stereo boom of the 1950’s. Most suffered from extreme depth distortion due to too wide a stereobase and lenses of too short a focal length. The images were adequate for the photo salons where a daffodil trumpet stretched to twice its normal length could be intriguing and dramatic but the same extreme depth distortion in an image of the human mouth is positively neanderthal.”
You can read all of Stan’s article “A Macro Stereo Camera”, see how he solved the tiny 4mm base, see how he was able to obtain fantastic results for Dr. J. M. Symington of the U of T, in the pdf file for issue 15-3 on the free PHSC DVD. See above or to the right to join or renew. Questions? Contact our Membership Secretary, Lilianne Schneider at member@phsc.ca.
