[photo-3d] Re: Origin of Phantograms - 2

[Abram Klooswyk <abram.klooswyk@xxxxxx>]

Steve A. Hughes Jul 20, 2000 :
> (...) looking for information on anaglyph figures or photos that
> appear to stand above the page when viewed at an angle. 

Bruce Springsteen Jul 18, 2000:
>(...) books I had come across, mostly involving technical 
>drawing, molecular models, and such visualization  tools.
>One such example is "Descriptive Geometry With '3-D' Figures" 
>by Imre Pal.

I have this book by Imre Pal, in an Hungarian edition, which I 
cannot read :-(, but the anaglyphs speak for themselves. There 
are also readable references in the book (I readable mean in 
English, German or French), some go back to 1912. Koo Ferwerda 
also refers to a Descriptive Geometry book (by Ernst 
Schörner), in German, which I also have. 

When you really want the oldest references (what for?), you 
probably will have to search in early 20th century books on 
descriptive geometry (German: darstellende Geometrie).

However, the condition "when viewed at an angle" in those 
early days was probably not considered an important issue. 
Moreover, _any_ anaglyph, or indeed any stereopicture in 
general which comes out off the page, can be viewed at an 
angle, but then they the 3D image shows distortion. So to 
the condition must be added: "seen without distortion".

When you drop this addition the oldest standing out drawings 
of course are some of Wheatstone's 1838 drawings. The square 
and the round frustum, and the cone all stand out off the 
paper. Even more interesting is his drawing which presents 
"a line in the vertical plane, with its lower end inclined 
towards the observer". 
When you look at this drawing with an about 45° angle to the 
page, the line becomes perpendicular to the page, _as if_ the 
drawing was designed to be viewed in this way.

Wheatstone emphasized that he had made the drawings using a 
method from descriptive geometry, which then was a relatively 
new technique. Anaglyphs were invented only towards the end 
of the 19th century.

Abram Klooswyk