Abstract
At this moment fundamental changes in sensors, platforms and applications are taking place.
Market needs for the use of airborne and spaceborne imagery are changing. Soon there will be new
high resolution spaceborne sensors available. Besides Photogrammetry new thematic applications will
drive the future image market. Needs like cost saving, time saving, higher and reproducible radiometric
resolution or spectral information will drive the change from analog to digital imagery. High resolution
satellites will compete with airborne film based photography and digital camera systems.
During the last 20 years several airborne sensors working with high resolution CCD lines were
developed and tested. High resolution CCD matrix sensors with several million pixels are nowadays
also available as a result of high resolution professional photography. But a digital camera is more than
only the exchange of film against silicon. The number of picture elements is only one parameter. As-pects
like data transfer rates, in-flight data storage, image archiving, geo-referencing, color fusion, cali-bration
and preprocessing have the same influence on the economical assessment of a digital camera
system. The paper describes actual development activities and application aspects of a modular digital
airborne camera system.
1. Introduction
For many decades Aerial Cameras developed and manufactured by Carl Zeiss Photogram-metry
Division have been successfully used all over the world as high performance systems for aerial
photography. Since April 1, 1999, this Carl Zeiss tradition is being continued by the Z/I-Imaging
GmbH Oberkochen. Z/I IMAGING will cover the entire photogrammetric workflow end-to-end. Aerial
mapping cameras like the RMK-TOP have been used for decades. In recent years they have evolved
from purely airborne cameras into complex system solutions through the compensation of aircraft mo-tions,
photoflight management with GPS navigation, and the use of measurement methods for the pre-cise
determination of the exterior orientation. 230 mm wet film with different specifications is still be-ing
used in a wide field of applications for image taking and image storage. This camera systems are
mostly used for mapping applications with photo scale between 1:5.000 and 1:15.000.
2. Airborne Remote Sensing Market
To establish a market for digital airborne cameras, they have to offer clear advantages in com-parison
with film based systems. For each application an investigation is required to define the digital
advantages. An analysis of the technical capabilities of digital imaging sensors in the photogrammetric
workflow allows the benefits for the overall process to be assigned to 4 groups :
- cost saving
- time saving
- higher image quality
- new applications
Process analysis and the technical capabilities of digital cameras - advantages and disadvan-tages
- show that the development of a new digital airborne camera involves much more than just the
substitution of a piece of silicon for analog film. The photogrammetric resolution of 230 mm aerial film
cannot be matched complete by silicon chips in the foreseeable future. Digital airborne cameras will
therefore not supplant aerial mapping cameras in the first step. Before substitution can take place, all
procedural steps from taking the photo and plotting it to archiving must be able to process the expected
data volumes economically. The market segments for digital airborne cameras and aerial mapping
cameras will therefore differ at the beginning. Of course there will be a common overlap area.
3. Market Forecast
The aerial image market as demand originator
for airborne cameras is a part of the GIS market.
The future development of this market has been
investigated in various market studies (CEO
1995, Dataquest 1996, EIA 1994,
Frost&Sullivan 1996, OTA 1994). All this mar-ket
surveys show a significant growth in the
decade from 1995 to 2005 (Figure 1). Interest-ing
are the changes in the market segments Na-tional
Security and Civil Administration on one
side and Commercial Applications on the other
side. A major trend seems to be that the public
sectors will stagnate or shrink and a clear
growth impetus will only come from new com-mercial
applications. This area will grow by
approx. 500% and this area will drive the need
for new digital cameras.
Figure 1: World GIS - Market Forecast
3.1 . Future Airborne Applications
For the conception of new airborne camera systems, the opportunities resulting from these
changes in the GIS market have to be considered. The demand in classical aerial imaging applications
such as cartography will stagnate and perhaps even shrink in the coming years, while a market segment
for new commercial applications will develop (Table 1). In part this involves applications from the
field of remote sensing, which benefit from the expanded spectral capabilities of digital imaging sen-sors.
As can be seen from this survey, these commercial applications have some quite different re-quirements
than map production by means of analog aerial imagery.
