Data rate was, in continuous mode, 1 second for block I, 
and 0.5 second for block II and III. 
Aerial camera was fixed along the strips. Eccentricity 
vector from GPS anten to camera in aircraft was surveyed 
on ground by tachymetric measurements. Horizontal and 
vertical components are sequentially 14 cm., 3 cm. and 
164 cm. . 
3.3. Data Processing 
GPS data were downloaded to laptop PC’s in real time and 
data processing was performed by using SKIP (Inpho 
GmbH) software. The GPS observations are differential 
phase observations of the L1 signals and C/A code pseudo 
range observations. 
Phase ambiguity is solved approximately, using 
pseudorange observations in SKIP software. Positions 
were reduced by eccentricity vector during data 
processing. 
The exposuring time of the camera was recorded by the 
GPS receiver in the aircraft, by means of an electronic 
pulse, sent automatically from camera to receiver. A third 
degree polynomial interpolation is done by the program. 
GPS positioning results are referenced to WGS 84 
coordinate system. The local coordinate system is UTM in 
Turkey. Datum transformation parameters from WGS 84 
to ED 50 were introduced to program and an initial 
transformation was provided during the data processing. 
Final transformation was solved in block adjustment. 
The GPS data had no any serious problem. There were no 
missing epoch or observations less than four satellites 
Table 2. Empirical Results. 
inside the photo strips. Data recorded by a stationary 
receiver located in settlement area, had detectable 20 
cycle slips. As it expected normally, the geometry of 
satellite was good and the mean value of dilution of 
precision of 3-D positioning (PDOP) was lower than 3. 
4. BLOCK ADJUSTMENT 
Planicomp C 100 (Zeiss) analytical instrument was used 
for photogrammetric measurements and both photo and 
model coordinates were stored . All three blocks were 
adjusted first in standard control point configuration 
(i-2b, 4b) according to the bundle (PATB) and 
independent model (PATMR) methods, without GPS data. 
PATB-GPS software was used for combined 
photogrammetric — block ^ adjustment. The block 
configurations can be shown in figure 1., 2. 3.. The 
interpolated GPS antenna coordinates are introduced into 
the combined block adjustment as additional observations 
for each camera position. Control points selected at the 
corners of the block are used to solve datum 
transformation and six drift parameters which is applied 
for every strip. 
First, the solution with 12 additional parameters, later, 
normal equation matrix inversion was applied. Detailed 
information related to blocks are given in table 2. 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Block I (5 strips) Block IT (7 strips) Block ITT (9 strips) 
a. without b. with a. without b. with a. without b. with 
GPS GPS GPS GPS GPS GPS 
Apriori ^ Estimates and XY Z X/Y X/Y XY Z X/Y Z XN Z 
Weights (cm) Z (cm) Z (cm) (cm) (cm) (cm) 
Control Points 25 37 25 37 10 15 10 15 3 5 3 5 
Check Points 25 37 25 37 10 15 10 15 3 3 3 5 
GPS Measurements - 10 10 - 0 10 - 10 
10 
Photogrammetric 744 ZA 6p 6pn 6u 6pn 
Measurements 
Number of Photos 46 46 70 70 90 90 
Number of Image Points 919 928 1602 1602 2093 2093 
Available Control Points 
- Ground Control Points 27-206 8 8 33 32 4 6 37 36 8 9 
- Check Points 90° 31 107 23 45 42 66 62 20 19  |47 41 
Resulting RMS of Differences 
- Photogrammetry - GCP 18/19: 31 18/7 48 | 777 12 3/4 4 3/4 3 2/3 6 
- Photogrammetry - CP 26/23 spo5dsyaa 61 | 11/14 19 [1916 20 5/6 6 6/5 9 
posteriori ©, 6.934 7.81 p 6.14 p 6.22 p 517 4.88 u 
  
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996 
42