INTEGRATION OF THE NOS CAMERA CALIBRATION SYSTEM INTO THE IDPF 
Roop C. Malhotra 
Nautical Charting Division 
Charting and Geodetic Services 
National Ocean Service, NOAA 
Rockville, MD-USA 20852 
ABSTRACT 
The National Ocean Service (NOS) camera calibration system consists 
of several distinct phases of operation: multiexposure photography 
on a multicollimator, mensuration of calibration plate on a high 
accuracy comparator, and storage of calibration results in a data 
base for further use in various photogrammetric projects. The 
integration of the calibration system consists of merging the 
mensuration, data processing, and storage phases of the operation 
into a unified software program. The entire operation can be 
performed on an integrated system, such as the NOS Integrated Digital 
Photogrammetric Facility (IDPF). In such a system, once the operator 
measures the multiexposure, multicollimator camera calibration 
photographic plate, the integrated computer program manipulates the 
data and stores camera calibration parameters in the IDPF data base. 
The data base is available to users at any one of the photogrammetric 
work stations in the IDPF network. 
KEY WORDS: Camera, Calibration, System, Integration, Digital, 
Photogrammetry, Multicollimator, Data Base, Network. 
INTRODUCTION 
An innovative camera calibration system has evolved at the NOS 
Nautical Charting Research and Development Laboratory, which yields 
camera calibration results, that are compatible in accuracy as well 
as in form (digital) with the requirements of the NOS IDPF. The IDPF 
controls a highly automated digital environment for performing all 
photogrammetric office processing. 
In order to support the IDPF and applications demanding highest 
possible accuracy, a + /-1 to +/-3 micrometers accuracy must be 
achieved in the linear parameters of camera calibration. NOS has two 
accuracy requirements for camera calibration, 'very high' and 'high'. 
The very high accuracy requirement of +/-1 micrometer is for the 
calibration of special aerial mapping cameras, which are equipped 
with reseau, and used for very high accuracy applications, such as 
photogeodesy. On the other hand, the high accuracy camera 
calibration requirement of +/-2 to +/-3 micrometers is for the 
calibration of standard aerial mapping cameras which are used for 
photogrammetric applications in mapping and charting. Furthermore, a 
camera tends to deviate appreciably in its calibration parameters 
with time and usage for which reason cameras must be calibrated 
periodically. Based on the above considerations, NOS, has a general 
requirement for calibrating aerial mapping cameras every 2 years. In 
view of these requirements, it is desirable that NOS have an in-house 
camera calibration capability to assure quality photogrammetric 
products.