More "War Stories" about stereoplotters. Message-ID: <01I0I8WZWTOI90X6C9@xxxxxxxxxxxxxxxx>

RE: Anecdotes on 3D mapping contraptions...cont'd 

The little white disks referred to include the Multiplex Plotter (WWII), the B&L Balplex Plotter (Korean War) and the ubiquitous Kelsh Plotter. Cold War instruments used by the U.S. included the M-2 (similar to the Kelsh) and the very, very classified M-4 used with the CORONA KH-4b Spy Satellite Panoramic chips (now unclassified per Photogrammetric Engineering issue of June 1995). 

The handwheel contraptions were (and still are) manufactured in many countries including Germany (Zeiss & Jena) C-5 & C-8 stereoplanigraphs, Switzerland (Wild) A-5, A-7, A-8, A-10, etc. and (Kern) DSR-3, etc., Italy (Gallileo/Santoni) etc., ... etc.
This type is in effect, a gigantic "Etch-A-Sketch" toy. 

When I lived in Boston in the early 1970's I worked as a Photogrammetrist at a mapping company. The supervisor for the WILD A-10 Stereoplotter operators had been a "Lefttenant" (sp?) in the Royal Engineers in WWII. They had British handwheel plotters back then, and the instruments had excellent optics. As others have recently mentioned the "difficulty" of viewing stereo with these instruments; with practice it becomes quite easy. Anyway, they were preparing for THE Invasion, and were working double shifts since there were so few Lefttenants that were accomplished Photogrammetrists. After doing this seven days a week for months, the entire group of Officers were successfull in compiling the requisite topographic maps to support the Invasion at a price. They all experienced atrophy of the eye muscles and had to be checked into a hospital for some number of days or weeks (I don't remember which from the story) to do eye exercises in order that their both eyeballs could track in unison and see normally again... He explained that it takes so little effort to focus at infinity while viewing stereo in a well-adjusted stereoplotter that their eyes received insufficient exercise to maintain muscle-tone over such a protracted period. 

I don't know if the story is true, but it is what Mr. John Baber told me back in the early 1970's...

Clifford J. Mugnier (cjmce@xxxxxxx)
Topographic Engineering Laboratory
Department of Civil & Environmental Engineering University of New Orleans
New Orleans, Louisiana 70148
Voice: (504) 286-7095
FAX:	286-5586




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