EuroSDR Projects - Host Ireland

Espoonlahti Hermanni Senaatti
Photos Stereo pair Stereo pair Stereo pair
Date 26 th of June 2003 4 th of May 2001 24 th of April 2002
Camera RC-30 RC-30 RC-30
Lens 15/4 UAG-S, no 15/4 UAG-S, no 15/4 UAG-S, no
13355
13260
13260
Calibration date 22 nd of November 18
2002
th of January 14
2000
th of April
2002
Flying height,
scale
860 m, 1:5300 670 m, 1:4000 660 m, 1:4000
Pixel size 14 microns 15 microns 14 microns
Pixel size on the
ground
7.5 cm 6 cm 5.5 cm
Table 2-1: Aerial images.
Espoonlahti Hermanni Senaatti
Acquisition 14 th of May 2003 End of June 2002 14 th of June 2000
Instrument TopoSys Falcon TopEye TopoSys-1, pulse
modulated
Flight altitude 400 m 200 m 800 m
Pulse frequency 83 000 Hz 7 000 Hz 83 000 Hz
Field of view ± 7.15 degrees ± 20 degrees ± 7.1 degrees
Measurement 10-20 per m
density
2 7-9 per m 2 on the 1.6 per m
average
2 on the
average
Swath width 100 m Ab. 130 m Ab. 200m
Mode First pulse 2 pulses First Pulse
Table 2-2: Laser scanner data.
Helsinki City Survey Division granted permission to use their material (aerial photos, laser scanner
data and cadastral maps) for the Senaatti/Hermanni data. Terrasolid Oy also gave permission to use
the Hermanni laser scanner data (partly owned by them). FM-Kartta Oy gave permission to use the
Senaatti laser scanner data in the project. The Espoonlahti laser scanner data is owned by the FGI and
permission to use the data in the project was granted. Espoonlahti aerial imagery was purchased from
FM-Kartta Oy for this project using internal funding of FGI. Espoo City Survey Division granted
permission to use cadastral map vectors.
Airborne images were in TIFF-format, with orientation parameters and ground point coordinates that
could be used as control or check points. Laser scanner data was in ASCII format (XYZ point data).
Cadastral map vectors were in DXF-format.
In the preprocessing of Senaatti and Hermanni data, laser scanner data was matched visually to map
vectors in the XY-directions and height was shifted using known height points. These shifts were
done after the original laser scanner observations were transformed from WGS84-coordinates to a
local rectangular coordinate system. The coordinate system for all data was local rectangular, with
origin at X(easting)=50000, Y(northing)=20000 and ellipsoid WGS84. In Espoonlahti, the coordinate
system for all data was the Finnish National Grid zone 2 (Kartastokoordinaattijärjestelmä KKJ)
projection Transverse Mercator, ellipsoid International (Hayford) (scale factor at central meridian
1.00000, longitude of central meridian 24 00 00 E, latitude of origin 00 00 00, false easting
2500000.000 meters, false northing 0.000 meters).
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