potomod lite contest. “city of badajoz (spain ) at years 1945 and

POTOMOD Lite contest. “City of Badajoz (Spain ) at years 1945 and 1956” by Francisco Bascón Arroyo [email protected]

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1. CONTACT

Project tittle: City of Badajoz (Spain) at years 1945 and 1956.

Company: Autoself employed, future web site: www.topoaerea.com

Name & email: Francisco Bascón Arroyo. [email protected]

2. PROJECT INFO

Input data description. This work is about two historic photogrammetric flights in Badajoz city

(Spain). This flights was complete by the USAF in the 1940´s and the 1950´s. They are the

oldest complete photogrammetric coverage from the spanish territory and other european

countries too:

a) The first flight was in 1945-46. Using the Fairchild K-17 reconnaissance camera with 9 x

9 size and 6” EFL. Scale 1:43000. Ground control points (GCP) taken from current

vector maps at 1:5000 and 1:10000 scale, I didn´t survey GCP with GPS. The images

are provided by CECAF at 1200 dpi and 8 bits using ZEISS Photoscan TD

b) The second flight in 1956. Using the Fairchild T-11 mapping or photogrammetric

camera with 9 x 9 size and 6” CFL. Scale 1:30000. Ground control and images data are

the same from the before 1940´s flight.

Hardware profile.

Component Description

Micro Pentium I3, 8 Gb RAM and 500 Gb HD

Graphics Nvidia Quadro FX 4600

GPU Nvida Tesla C1060

3D system Benq XL2420T monitor & Nvidia Vision2 glasses

Table 1. Hardware profile

Project Workflow description.

The first main step was to compute a good camera calibration parameters because the flights

are 65 years old and today there aren´t calibration certificate or any other info aviable about it

in Spain. So I needed to make a reseach to know what camera they used and many other data

or info about the flights. This research was done at several countries with the same flights:

Italy, Portugal and Spain. In the USA too, because they made the flights. I only could do the

research by email request but It worked so good.

The next step was another but minor problems. It was find GCP because 65-50 years later

many of them are not remain today. I needed make georreferencing of half aerial photographs

using GIS, so it was more easy and quickly to find the GCP. The bad radiometry has been

http://www.topoaerea.com/

mailto:[email protected]


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improve correcting vignetting effect but the brightness across strips still remains. It will need

MatLab procces to enhace.

The flight at 1956 is more accurate so I only drew stereovector on the 1956 flight for the

features that appears at both, 1945 & 1956. Later PhotoMod computed the auto match points,

they was different for the two projects. The DEM was obtain with auto points and

stereovector. The final orthophoto was obtained.

The historic research time was about 6 months and later the photogrammetric procces was

about three weeks. Both procces aren´t at full time.

Output results description.

The following table shows some photogrammetric data results

Flight 1945 1956

DEM grid 50 25

GSD Ortho 1.25 1

Accuracy. ASPRS test

4 2.5

Scale to work. From ASPRS test

1:20000 1:10000

Stereovector object

S/N 453

Area (Km2) 146 49

Table 2. Photogrammetric workflow summary

I used seven codes to draw stereovectors (road, trail, railroad, wall, river, stream and contour)

The future use for this data will be accurate survey from propietary boundaries, public or

prívate and the timeline of geo-temporary natural process.

I spoke to my university professor and he encouraged and helped to me to write a paper

together. We worked about the historic research for the flights and the improve of Interior

Orientation of the 1956 flight camera by computing accuracy custom calibration reports. One

paper, for the 1945 flights, has been accepted as pre-print for the TopCart 2012 iberoamerican

congress, Madrid October 2012. The other paper, for the 1956 flight, today we still working to

write, near to send a journal.


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Graphic samples.

Picture 1. Block layout from 1945 flight. You can see the brightnees strips

Picture 2. Block layout from 1956, flight with stereo vector. Black area is Portugal, agreement excluded thirds nations involved


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Picture 3. South city of Badajoz at 1956 with Vauban fortifications stereovector, semi-demolished and not complete

Picture 4. Badajoz railway station and Guadiana river joins his afluent Gévora. Left part at 2007 and right at 1945.


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Picture 5. Front ortho from Badajoz city at 2007, middle at 1956 and back at 1945.

Picture 6.From left to right, Badajoz city at 1945, 1956 and 2007.

potomod lite contest. “city of badajoz (spain ) at years 1945 and

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