GEOMETRIC AND RADIOMETRIC EVALUATION OF THE POTENTIAL OF A HIGH 
RESOLUTION CMOS -CAMERA 
F. Samadzadegan *, M. Hahn”, M. Sarpulaki“*, N. Mostofi® 
"Dept. of Surveying and Geomatics, Faculty of Engineering, University of Tehran, Tehran, Iran - samadz @ut.ac.ir, 
mostofi_n@ yahoo.com 
"Dept. of Geomatics, Computer Science and Mathematics, Stuttgart University of Applied Sciences, Stuttgart, Germany — 
michael. hahn € hft-stuttgart.de 
"National Cartographic Centre of Iran (NCC), Tehran, Iran - sarpulki ?ncc.neda.net.ir 
Commission WG III/5 
KEY WORDS: Radiometry, Geometry, Accuracy, Close Range, Calibration, Photogrammetry 
ABSTRACT: 
The progress of digital imaging systems has created manifold opportunities and new applications to close range photogrammetry. 
The classical techniques have found significant changes and this seems to be an ongoing process which is heavily influenced by new 
technologies showing up on the sensor market. CMOS (Complimentary Metal Oxide Semiconductor) sensors are on of the 
challenges to CCD sensors as they are providing a similar performance at a cheaper price level. One of the demands is to investigate 
the radiometric and geometric characteristics of the imaging sensor. This includes considering other factors involved in image 
acquisition with CMOS sensors and requires a detailed analysis on the factors and its effects for the overall performance of CMOS 
cameras. This paper analyses the radiometric and geometric performance of the Canon EOS-1Ds, a high resolution CMOS camera. 
Presented are issues of restoration and geometric correction as well as an experimental investigation using different Canon EOS-1Ds 
images. Visual inspection and quantitative analysis of the obtained results demonstrate the high productive capability of the Canon 
EOS-1Ds camera. 
1. INTRODUCTION 
For more than 25 years, CCD (Charged Coupled Device) 
technology was the leading technology in the image sensor 
industry. With the CMOS technology a competitor to CCD 
technology has entered the image sensor arena. CMOS 
(Complimentary Metal Oxide Semiconductor) sensors are 
challenging the CCD market by providing similar performance 
in a much cheaper package (Findlater, 2001). Both CCD and 
CMOS are manufactured in a silicon foundry and the base 
material and equipments are similar. The main differences are 
due to architecture, design and flexibility of CMOS that can be 
integrated on-chip thus leading to a novel family of compact 
imaging devices. 
Figure 1 shows the expected trend in image sensor migration of 
CCD and CMOS devices for various applications. CCDs will 
continue to dominate in high-performance, low-volume 
segments, such as professional digital still cameras, machine 
vision, medical, and scientific applications. But CMOS will 
emerge as winner of low-cost, high volume applications, 
particularly where low power consumption and small system 
size are key features. From a technical point of view, several 
criteria are used to evaluate imaging sensors; among them are 
responsivity, dynamic range, uniformity, speed, and reliability. 
Regarding responsivity which is a measure of the signal level of 
optical energy per unit) CMOS sensors are slightly better than 
CCDs (Taylor, 1996). Gain stage on-chip and complimentary 
  
*Corresponding author. 
  
   
    
   
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Low power consumptio 
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1970 1980 1990 2000 2010 
Figure 1. Trend in image sensor migration of CCD and 
CMOS devices for various applications. 
transistors result in relatively high gain with low power 
consumption of CMOS sensors. CCDs require much more 
power because the amplification is implemented off-chip. 
Another category for comparison of the two technologies is its 
dynamic range. The dynamic range is the ratio of the saturation 
signal to the noise floor measured at zero exposure. This 
quantity is much better in CCD technology because it has less 
on-chip circuitry, which increases the noise immunity of the 
sensor (Seibold, 2002). External amplification also gives greater 
control over noise levels. CMOS sensors are more susceptible 
to uniformity because each pixel has its own amplifier. From a 
speed point of view, CMOS sensors operate faster because most 
     
  
   
    
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
    
    
   
    
     
     
     
   
   
   
   
   
   
   
    
   
   
  
    
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