Jauregui, Luis M.
To obtain a digital image, there are two means: directly, using a digital camera, or by the use of a scanner; this one is
still preferable to the digital camera, because we can have a greater amount of pixels if we scan an enlargement, so the
final image can be plotted at a scale 1:50 or 1:25 without loss of detail.
The processing of the image is made up in three forms. At first, it has to receive pictorial improvements, as contrast, hue
and luminosity. With the image improved, the rectification is made; sometimes, in very simple façades, a rotation and
scale will be enough. The third operation consists in eliminate of the image the elements that not belong to the facade.
The Institute of Photogrammetry of the University of Los Andes, had under his responsibility to make the aerial and
terrestrial photogrammetrical surveying and the photointerpretation of a zone occupied by
mission's town, founded in 1620, and abandoned two hundreds years ago. To achieve this
rectified digitased fronts and digital orthophotomaps from zones of archaeological interest w
shows an example of application of this technique.
the ruins of an ancient
objective, techniques of
ere carried out. Figure 4
Figure 4. Restitution superimposed on digital image of the Church ruins of Mucufio, Venezuela.
4.4 Use of small format aerial photography
The Laboratory of Photogrammetry of the Forestry Sciences Faculty, lent the camera used in this mission. It was a
Hasseblad 553 with a lens of 40mm focal len
gth, using Kodak Vericolor film, and equipped with an intervalometer
home-made. The camera mounting, also of this laboratory, was of the lateral luggage door type, made to fit in a Cessna
182 aircraft. The fact of flight over a closed zone with strong winds, obliged to make the photographs a little early in
the morning (10:00 a.m.), with the disadvantage of have
a disturbing shadow in the ruins. Another consecuence of
topography of the place was that the flight had to be made against slope. A total of two strips with 5 pictures each was
taken of the town of San Antonio de Mucuño,
at 2000 m height and a scale 1/15000. The restitution of the models was
superimposed over the scanned pictures rectified, as shown in figure 5.
Figure 5. Small format aerial photograph of archaeological site, with superposed plannimetric information.
404 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B5. Amsterdam 2000.
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