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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B5. Beijing 2008 
Keeping also in mind global archives of satellite and aerial 
photography, it is estimated, currently easy at least some 
million historic analog stereo views still wait for digitization, 
for modem spatial data presentation, for restoration and 
comparison purposes etc., see samples in Figure 2,3,4,7 and 8. 
As a matter of fact, the benefit of a complete additional 
dimension from systematic 3D photography for 
documentation purposes is still underestimated and even 
doubted. For heritage documentation purposes in particular 
subjective interpreted manual drawings instead of objective 
high resolution 3D photography at least are preferred partly. 
Therefore it is the authors’ suggestion, for documentation 
purposes, consequently to replace subjective manual sketches 
by objective 3D images, compare Figure 3. 
3D images often are not directly available or show lack in 
resolution. For this cases extremely high resolution low 
altitude aerial (3D) photography from a 15m carbon telescope- 
rod and from a captive balloon successfully has been obtained. 
This will more and more become an objective tool for a huge 
range of documentation purposes, in particular in archaeology. 
This “3D-niche-photography”is also well suited under 
expedition constraints and promises a great future, see also [4]! 
The invention of the telescope-rod camera by the authors has 
been adopted by Heinz Ruether for detailed stereo image 
covering of archaeological sites in Africa and of course it is 
very suitable for Australia as well, see Figure 3 (left). 
Depending on the height, the base length of the lite digital 
camera can vary. Nowadays for serious photographic 
documentation at least 3D photography should be preferred! It 
is liked to emphasize, due to the modem camera Technology, 
single lens cameras of both types, analog and digital, for 3D 
photography of static objects even seem superior to old 
fashioned stereo cameras! Another big advantage of single 
lens cameras is the relative low price, the light weight, easy 
handling and the flexibility in base length variation. 
3. RESEARCH TOPICS IN 3D IMAGE ASPPLICATION 
The 3D-Image Application already dates back to the British 
Physician Wheatstone. Who invented the stereoscope in 1832, 
compare Gernsheim (1965). The virtual 3D visualization 
Technology as a part of Geoinformationsystems (GIS) is very 
advanced, Nevertheless dealing with basic research in this 
field still leads to a surprising number of open research topics 
in Technique and/or Arts aspects of 3D image application. 
Identified open research topics in 3D-image application, 
which are still not or not yet completely solved are listed and 
partly described in the following, without claiming for 
completeness: 
Open research topics for Technique and Arts aspects of 
3D images: 
The stereoscopic perception ability while viewing on 2 
corresponding stereo mates is part of the human 3D viewing 
sense. Independent of the nature of the horizontal parallaxes, 
also known as disparities, an attempt for a systematic 
investigation of the complete list of virtually stereo aids 
according to the state of the art, has been carried out. 
Constraints are: at least 2 stereo mates of real and/or synthetic 
origin, showing the same object, as imaged from different 
positions, approximately perpendicular to a base line with 
satisfactory parallel imaging directions. 
1. 3D perception of in minimum 2 stereo mates, vertical or horizontal arranged, but “projected without 
contact”; for "ortho" or "pseudo"as well as for normal and/or cross 3D visualization: 
1.1 AUTOSTEREOSCOPIC VIEW of horizontal mounted 3D views, see Figure2,4,6, 7 and 8 
1 2 MAGIC EYE / RANDOM DOT 
1.3. HEAD MOUNTED DISPLAY 
1.4. LENTICULAR LENSES for vertical, horizontal or arbitory interlaced stereo mates:(e.g.,“3D POSTCARDS”)or 
1.5 STRIP BARRIER: vertical or horizontal interlaced stereomates appear remind, to 1.4, but without 
lenses,s.Figure7 
16 STEREOSCOPES: 
1.6.1 LENS STEREOSCOPES, see Figure 7(left) 
1.6.2 MIRROR STEREOSCOPES with LENSES 
1.6.3 Mirror stereoscopes for horizontal arranged stereo mates; vertical mirror: PIGEON, see Figure 2 
1.6.4 Mirror stereoscopes for vertical arranged stereo mates; horizontal mirror: DOWN UNDER, see Figure 1 
1.6.5 PRISM-STEREOSCOPES for horizontal mounted stereo mates 
1.6.6 Prism-Stereoscopes for vertical arranged stereo mates: KMQ 
2. Methods for virtual spatial perception based on stereo mates, “projected in contact”, using alternate 
projection and/or different color: 
2.1 ANAGLYPHS (complementary color (green/red or blue (magenta)/red or magenta/yellow separation) 
2.2 CROMADEPTHS (spectral color separation) 
2.3 POLARIZING FILTER Techniques 
2.4 (Liquid Crystal-) SHUTTER glasses 
2.5 NuOptix 3D Movies for (relative) moving objects for PULFRICH GLASSES, also used in CYBER SPACE 
3. 3D perception Techniques using VIRTUAL 3D MODELS: 
(3.1 MIRROR) 
3.2 moving screen: - Rotating Screw Shaped Screen (FELIX ) 3D) 
- or up and down Oscillating Screen ( BOLLOGRAPH) 
3.3 (FELIX) 3D - SOLID STATE crystal = new 3D PC/TV-screen generation? 
3.4 HOLOGRAM Technologies 
Table 1. The updated complete list of virtual spatial visualization Techniques (Status: 2008).