ce you have the 
ecause with the 
ietric calibrated 
80mm lens. We 
t with a remote 
Ly centre of the 
is exactly under 
er. Also the tray 
stic absorbers in 
the rotor on the 
n Trainer model 
tion such as the 
e used. Another 
etween the new 
| the camera. In 
ig photos in the 
  
s in Rentina 
rveyed a site in 
untry house in 
he construction 
| Greece. In the 
cond effort and 
xample. In the 
measured with 
e control point 
)pter at 30-40m 
ale of 1:400 to 
ind we have to 
| operation time 
rol points. The 
the operator of 
the Helicopter and the other the operator of the camera. The one 
that operates the camera was an experienced surveyor who was 
leading the operator where to fly the model in order to take the 
right shots. After 4 weeks another series of photos was taken 
because we wanted to register the progress of the excavation. 
From the photos that we took 5 have been used to produce the 
orthophoto shown in fig. 2. The black crosses in this figure are 
the crosses from the back of the camera. 
  
Figure 2. Orthophotomosaic produced from the photos 
In the office we scanned the photos, we solve the 
aerotriangulation using the data for the control points, we 
produce the DTM in order to create the orthophotomap and then 
we compose the mosaic of the orthophotos (fig. 2). This is an 
one man work for 10 days after the film developing. The final 
products are orthophotos at a scale of 1:100 and 1:50. Also a 
plan was drawn at a scale of 1:50 (fig. 3). 
4. CONCLUSION 
The choice we made to use the model helicopter as platform to 
take the photos for surveying archaeological sites has: 
* Reduced the time needed for preparing the effort 
® Reduced the cost of taking the aerial photos of the site 
* Reduced the disturbance of the people working in the site 
® Reduced the total work time for making the survey 
* Reduced the flight altitude giving grater scales and details 
* Reduced the time of process for the final product 
* Gave an ideal product with all the information 
Apart from the above mentioned the difference between the 
orthophoto and the drawing can easily be detectable as we 
observe figures 2 and 3, those plans have exactly the same 
accuracy while the time and the cost needed to form the 
  
drawing is three times the time needed to compose the 
orthophoto. On the other hand on the drawing we can see only 
lines which have been interpreted from the operator of the 
photogrammetric station, sometimes the archaeologist has 
difficulties in understanding those lines while on the orthophoto 
anybody can easily recognise details and colours. This gives the 
opportunity of a better interpretation and at the same time we 
have available all the geometric information of the drawing. 
« Figure 3. Detailed plan of the excavation 
Another application that is in research for the time is the use of 
infrared films in different daytime and in different types of soil 
with observations on the ground humidity in order to seek 
whether is possible to locate underground findings for 
archaeological purposes. This effort is really in the very 
beginning for our team and we have no results yet but we 
believe that there is a lot of consideration in this. 
However using the above mentioned techniques for surveying 
the archaeological sites gives the ability of creating dynamic 3D 
models using the virtual reality methods. It is very easy using 
s/w to inspect the site virtually, to walk through, and to view 
from various points the findings and even more to take 
measurements on this 3D model. In fig. 4 we can see the site 
that has been surveyed in a 3D model. 
REFERENCES 
Georgopoulos A., Nakos B., Mastoris D., Skarlatos D., Three 
Dimensional Visualisation of the Built Environment Using 
Digital Orthophotography, Photogrammetric Record 
15(90):913-921, 1997 
Dallas R. W. A. Architectural and Archaeological 
Photogrammetry, Close Range Photogrammetry and Machine 
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