A RENAISSANCE OF ARCHITECTURAL ENDOSCOPY?
Vienna University of Technology
Before individual activities in the field of endoscopy are to be
explained a brief insight into the surrounding thereof may prove meaningful.
At the Department for Spatial Simulation endoscopy is not treated
independently, but principally in connection with other simulation techniques
such as the simulation of architectural spatial formations in full-scale,
CAAD, stereoscopy and holography.
The term SAAD (Simulation Aided Architectural Design)
[The term "SAD" (Simulator Aided Design) was coined at the likewise named
SAD-Laboratory at the Tampere University of Technology]
refers to a combination of spatial simulation techniques.
This aspect plays a major role at the Vienna University of Technology.
The laboratory is situated in the main building of the Vienna
University of Technology at Karlsplatz. The facilities
available to the lab are directly adjacent to the centrally located
1st Courtyard and are accessible on the groundfloor via the courtyard
through the main entrance. Further linkages are located in the basement
and also lead directly to the stage area. The endoscopy area is also
located there next to the experimental stage and the respective storage rooms.
The experimental areaof the laboratory consisting on the ground floor is
surrounded by a working gallery open vault
Both from this gallery and from the working area on the ground floor one
can watch any on-going experiments The experimental stage has a clear
height of practically 9 meters and a working area of approx.
60 m2 The experimental floor and the ceiling resp.,
consists of adjustable girders and floor units making for
alterations of the floor area in any desired manner.
The panelling of the side walls consists of the same wood plates as the
floor units, so that things like screwing, nailing can be accomplished
without difficulties similar to work on a theatrical stage.
At the half height of the room the removable banister of the working gallery
becomes visible. The movable working platform has not only been designed
for mere observation purposes. It is supposed to be used for experimental work,
too, for suspending or positioning light-weight building members as well as
for the operation of lighting fixtures in the busbars provided.
Any lateral movements of this working stage are performed manually
by a person on stage using a hand crank. The experimental floor consist of
adjustable floor girders and panels making for any required height alterations.
This floor-modulation-installation was already taken into account while
construction work was under way, thus the later wall brackets were
dimensioned appropriately to be able to bear the required loads and
were equipped with holes every 17 cm.
Installation of the Lab Area for Endoscopy
The acquisition of a rigid endoscope in combination with a very inexpensive
CCD-video camera in 1989 set the stage for the first steps in the field of
endoscopy. A VHS-recorder with monitor was at our disposal as peripheral
equipment. Two years later the recording procedure was expanded to an extent
that "single frames" and "quicktime movies" now are transferrable
unconditionally into the computer and can be further processed there.
The complete equipment is designed for still pictures and simple sequences,
as these mainly deal with the special field of interior design.
Installation of mechanical equipment
- of a camera rig in order to control motion sequences -
is scheduled for the long run.
First equipment was installed provisionally in a seminar room,
even though the exposure table with background screen,
the light fittings and the endoscope with peripheral equipment had to be
installed newly for every recording set.
Meanwhile a better solution for this situation was found by adaptation
of an own lab area for endoscopy
Considerable improvements were accomplished with the initial equipping
of this area. A soft source (a so-called "windowlight" with 5000 W)
is mounted shiftably on two rails over the exposure table with background
screen. Sun is simulated with an additional light source (1250 W).
Presently a highly sophisticated ball-bearing studio tripod is being used.
The endoscope with a viewing angle of 50 degrees is mounted together with
a CCD-camera positioned appropriately for picture taking.
This miniature camera surely does not furnish top-quality pictures,
its robustness, however, has proved very useful regarding the amount
of handling it is subjected to by the students.
So required we can also rely on a C-mount adapter and furthermore
on a connection to the media center of the Vienna University of Technology.
The equipment as described above has been in operation since the end of 1992.
Image Processing as Main Goal
The unpopularity of endoscopy in the representation of architecture can be
traced back to problems in the peripheral area.
When viewing an architectural model by endoscope,
e.g. the definition of the picture is fine,
but the image the viewer receives is hardly conveyable to others.
In order to facilitate communication several experiments were made
to connect the endoscope with peripheral recording media:
Both as far as digital video and still-video are concerned overlappings
with photographic and film techniques can be determined.
Real pictures taken photographically are achieved providing
a considerably better definition by scanning,
so required, and mounting with the digitized videoframe.
For pragmatic reasons the AppleMacintosh-vicinity has been chosen
for work at the Vienna University of Technology.
Presently, it just does not work out that the entire working capacity
is dedicated to computer work.
Detailed considerations as to the advantages and disadvantages
of various operating systems would be too lengthy for this paper.
- a registered trademark of Adobe Systems -
is being used as image processing software.
Amongst others, it is characterized by a vast range of differentiated tools,
manipulation filters and plug-ins.
The lack of definition in the digitized output-picture resulting from the
was somewhat relieved by means of the filter "sharpen".
- A: Photographic Technique
- The endoscope is attached to the lens of of a reflex camera by means of
a transitional ring. Only still pictures can be made.
- Apart from transitional ring and spotlight,
so required, hardly any additional investments are required.
Comparing to video-pictures a much higher resolution is achieved.
- Endoscopes are of low light intensity and require a lot of light.
Working conditions when taking pictures seem rather unpleasant.
While the photographer is selecting the picture section
in the finder of the camera he is exposed to a considerable amount
of heat depending on the amount of spotlights being used.
Trial runs are required in order to define correct period
of exposure this making for frequent interruptions caused
by film development every time.
- A1: Film-Technique
- The endoscope is attached by means of transitional ring to the lens of a film camera.
- As in (A).
- As in (A).
The lower degree of light sensitivity cannot be made up for by means of extended periods of exposure.
- B: Video-Technique
- The endoscope is connected with the video camera by means of an adapter. As to suitability of camera no general conclusions can be made: it has to be tested for every specific instance.
- The result becomes visible directly on the monitor, i.e. any desired modifications can be immediately performed. The medium video is not principally limited to still pictures: movements and camera drives can be registered in various video formats (S-VHS, Betacam SP, Hi8, etc).
- Up to approx. 1980 only Ólow-qualityÓ video-cameras were available in the semi-professional field. The CCD-camera has, however, done away with this problem to a large extent. If no editing equipment is available, the raw material has to be further processed somewhere else.
- B1: Digitizing / Digital Video
- A computer plant with image processing software has to be equipped with a digitizing card which enables processing of e.g. PAL- or NTSC video-signals. Some software-packages have so-called plug-ins which import the images without detours. Export possibilities of computer sequences on video require further investments regarding the hardware (e.g. Genlock-Interface).
- As with video-technique
- Relatively high investments necessary.
A tremendously high memory requirement necessary when
e.g. real-time-sequences are to be depicted
(per second 25 with frame- and 50 with field-recording).
Quality limitations, however,
result anyhow by the PAL-video-system regarding picture resolution.
Thus the video-picture has to be digitized sufficiently large,
as subsequent "blow-up" is no solution
- Figure 3:
- B2: Still-Video
- For completeness sake still-video has to be mentioned.
Individual pictures are taken with a still-video camera and are stored
The pictures produced can be played on a monitor or may be processed
in the computer.
Any definite experience in connection with endoscopy
as far as registered has not been published as of yet.
- Storing in digital format by means of a small, handy camera.
- Still-video pictures so far only provide of a mediocre resolution.
Considering that endoscopic exposures are predominantly taken in
laboratories a good individual picture could be rescued from the
video tape, so required.
Then the picture was completed as the terrain of the model taken proved
too small. For this reason existing picture parts, such as the water surface,
The subsequent addition of human figures
(scanning in, scaling and positioning) could also be feasible.
So-called "facet-filters" were also put to use.
Lack of definition was thus softened even more by the effect
achieved by painting in water colors.
Finally the approx. 1.5 megabyte picture was transferred to the
EDP-center for diascoping
with a resolution of 2800 DPI [This equipment as presently configurated is
designed only for Postscript documents.Apple Macintosh rather works with
other formats e.g. Tiff and Pict. Luckily, we managed to proceed with
printing in the usual fashion by making use of software "Interprint"
by Intercon. The document is first translated into Postscript
and then checked into the printer queue.].
is showing the same model,
but viewed from a different site.
The question here is how the reflection of the building in the water
The required building parts were selected with the tool "magic wand"
and was copied into an additional document.
After vertical rotation the reflected picture information was inserted
in the original document and the reflection was accordingly distorted.
By means of mounting control convergence was reduced to approx. 70%.
Furthermore, the reflection in the water was manipulated
for the selected water surface with the filter "shear"
Expectations for the Near Future?
Principally, first encounters with the medium endoscopy should produce
This is to be interpreted that the demonstration is to involve potential
possibilities rather than exclusively stressing its limits.
Though 3D-computer simulations are presently in
fashion and endoscopy is rather considered as "out"
the short training time has to be particularly pointed out.
The required scale models are being built anyway and
only call for insignificant adjustments.
Endoscopy is not overloaded with theory;
students can tackle the subject in a "playful" manner.
The question is,
how many endoscopes have been purchased for architectural purposes
world-wide and how many of them are really still being used.
We do not have any exact figures, those having merely become
dust-catchers could be revived without too much effort.
The reinstatement could prove simple in the low-cost range,
as many universities and offices nowadays have efficient computer
plants at their disposal.
The variety is large starting with the simplest still picture
to the pre-programmed computer controlled movement via camera rig.
the mixture of "real" and produced reality (by means of endoscopy)
must be considered.
A renaissance of endoscopy could thus be envisaged at least
for still pictures.
As for the moving pictures the exposure and editing of sequences
via computer presently is only to be realized with certain limitations.
Despite compression procedures there is a tremendous storage requirement.
What seems likely is that the increased use of multimedia will inevitably
lead to advancements in the hard- and software area.
The combination of endoscopy and stereoscopy,
referring the taking of stereoscopic endoscope pictures
(both stills and animations)
is a practically unexplored research subject.
Also the combination with holography
- the endoscope acting here as a Holographic Optical Element (HOE) -
has so far not been investigated.
Finally, the endoscopic optics represent a further field of investigation.
The development of rigid endoscopes with high light intensity
could prove very beneficial.
With specific model simulations
- particularly regarding indoor areas -
lighting always poses a problem.
If the companies supplying endoscopes invested vigorously
in such advancements
(even though medical applications are by far much more
rewarding regarding commercial aspects),
endoscopy could probably gain in interest as far as applications
in the field of architecture are concerned.