The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
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pixel with view angel and relative position changing of the 
scatterers. The main characteristics of multi-image processing 
method are that it utilizes a single master stack of differential 
interferograms and that only time-coherent pixel. According to 
the description of the PS technique which base on Colesanti et 
al., Ferretti et al., the key processing steps of the PS technique 
are the following (1 Computation of the interferograms, (2) 
Computation of the differential interferograms using a digital 
elevation model, (3) Preliminary estimation of the presumably 
most coherent pixel, (4) Refinement of third step; the coarse 
grid of PS candidates estimate the long wavelength part of the 
atmospheric signal. After interpolation of these estimates, the 
differential interferograms are corrected, and additional PSs are 
computed [Ferretti et al, 1999, 2004; Hooper, 2006]. 
3. AERIAL PHOTOGRAMMETRY 
Traditionally, Photogrammetry has defined as the process of 
deriving metric information about an object through 
measurements made on photographs of the object. Aerial 
photogrammetry is the taking of photo from the air with a 
camera mounted on an aircraft, helicopter, and similar vehicle. 
Aerial photogrammetry is used in land-use planning, archeology, 
environmental and surface monitoring and other fields [Jensen 
2007]. In aerial photogrammetry, the reference coordinate 
system, or datum is defined by the Ground Control Points 
(GCPs) [Mikhail et al, 2001]. In this research, coordinate 
systems were defined to UTM-56 and WGS84. GCPs are 
surveyed by Leica GPS-500 system. Each GCP was measured 
using static method and operating time was over 30min. 6 GCPs 
were used. GCPs coordinate are table 1. 
ID 
Latitude 
Longitude 
Hight 
181 cp1 
-33.89042579 
151.2336121 
90.48899 
181cp2 
-33.88435260 
151.2489353 
56.73410 
181cp3 
-33.90650849 
151.2317450 
54.84594 
181cp4 
-33.90785047 
151.2474110 
91.80488 
181cp5 
-33.91723083 
151.2264035 
51.00231 
181cp6 
-33.91877307 
151.2459852 
55.55110 
Table 1. Coordinates of Ground Control Points 
Figure 1. GCP Surveying using GPS 
4. EXPERIMENT 
The test field is residence area at Sydney in the New South 
Wales, Australia. In the PSInSAR process, test field is covered 
all Sydney area (15x15km). In the aerial photogrammetry that 
to get detail information, test field is minimized small confined 
region ( 1.5 x lkm). 
Figure 2. GCP Surveying using GPS 
Figure 3. Aerial photo processing using SOCETSET 
Figure 4. Test Field in Sydney (Google Earth) 
This research used European Remote Sensing 1 and 2 (ERS- 
1/2) radar images (C-band) using PSInSAR and Aerial photo 
using Photogrammetry to investigate the ground deformation at 
Sydney in the state of New South Wales, Australia. The 18 
images of ERS-1/2 (04/1992-04/1997) were found in the search 
for the available images over the Sydney area. The Persistent 
Scatterer candidate identification process was progressed to 
identity all the stable natural reflectors according to the