Digital photogrammetric cameras: possibilities and problems (original) (raw)
Related papers
Digital Airborne Cameras-Status and Future
Proceedings of ISPRS Hannover Workshop, 2005
The traditional way of airborne photogrammetric imaging is undergoing major changes currently. With the advent and operational availability of digital (large-format) imaging sensors a strong and powerful alternative to the standard way of analogue imaging appeared. The ...
Ten Years Large Format Digital Aerial Cameras, a Review
Large format Digital aerial cameras were introduced 10 years ago in Amsterdam at the ISPRS Conference in July 2000. Only about 5 years later the digital large format aerial cameras had overtaken the majority of photogrammetric image production. The new technology did change the photogrammetric workflow, replaced well known components and made the end-to-end all digital production chain available to the photogrammetric community. Helpful if not essential was the development of computers, storage media, software products and other IT components which are the basis of any digital processing scenario. The development of large format digital aerial camera shows a specific evolution. Frame size, multi spectral capability, on board storage capacity and other details of such sensor systems are discussed within this contribution. The impact on the productivity of photogrammetric production units, the number of frames taken by one sensor during one year and the increasing appetite for geo data are as well topics of this article. Furthermore we discuss the development of photogrammetric software solutions and their ability to handle large volumes of pixel data. The need for automation and the introduction of new photogrammetric products are in focus. As a contribution to further discussions we try to give an outlook for the next few years and to ask ourselves the question if the photogrammetric community is well prepared for the next decade.
Experiences with Digital Cameras for Earth Observation
The paper reviews the methods of digital imaging for photogrammetric purposes. Currently, two architectures compete with each other: the full frame CCD array and the linear array CCD. It seems, that in a long term the full frame will overcome the deficiencies of low spatial resolution and small image format. But it is no question that for the time being three-line imaging is the leading concept for Earth observation. Two systems will be presented which are based on this architecture. The Modular Opto-electronic Multispectral Stereo Scanner (MOMS) of 2nd generation was designed for Earth observation from space, and the Digital Photogrammetric Assembly (DPA) as an airborne digital imager. Both systems have been flown over some testsites, resulting experiences and results are presented.
Performance of medium format digital aerial sensor systems
Proc. ISPRS Conf, 2004
Dealing with digital airborne photogrammetric data acquisition today's main focus is quite often exclusively laid on the large format digital sensor systems like ADS40 (Leica Geosystems), DMC (ZI-Imaging) and UltracamD (Vexcel Austria) which are already used in practice now. Their advantages are well known, nonetheless, for smaller area projects the use of such large format systems might be ineffective. Hence, there still is a need for smaller cameras which can be used in a more flexible and cost effective way. This application is addressed within the paper, where the main focus is on the medium format sector, utilizing digital matrix arrays about 15 Megapixel. After some first remarks on classification of digital matrix cameras the requirements for usage of non-dedicated sensors in airborne photogrammetric environments are recalled. The second part of the paper concentrates on the demonstration of the potential of two exemplarily chosen medium format cameras, namely the DSS sensor system from Applanix/Emerge, the dIGIcam-K14 sensor system from IGI and the Kodak DCS Pro 14n. The DSS is based on a classical analogue medium format housing which is supplemented with a digital CCD camera back, whereas the last two are using a standard small format camera housing with CMOS matrix array. The performance of such systems is proven from the results of airborne tests.
Airborne high-resolution digital imaging system
Journal of Applied Research and Technology
A low-cost airborne digital imaging system capable to perform aerial surveys with small-format cameras is introduced. The equipment is intended to obtain high-resolution multispectral digital photographs constituting so a viable alternative to conventional aerial photography and satellite imagery. Monitoring software handles all the procedures involved in image acquisition, including flight planning, real-time graphics for aircraft position updating in a mobile map, and supervises the main variables engaged in the imaging process. This software also creates files with the geographical position of the central point of every image, and the flight path followed by the aircraft during the entire survey. The cameras are mounted on a three-axis stabilized platform. A set of inertial sensors determines platform´s deviations independently from the aircraft and an automatic control system keeps the cameras at a continuous nadir pointing and heading, with a precision better than ± 1 arc-degre...
The Z/I Imaging Digital Aerial Camera System
1999
With the availability of a digital camera, it is possible to completely close the digital chain from image recording to plotting. The key decision regarding the camera design in this case is whether a CCD sensor should be used on a line or a matrix basis. In view of the high geometric accuracy requirements in photogrammetry, Z/I-Imaging focused its development on a digital camera based on a matrix sensor. An essential aspect of this decision was not only the aerial camera system, but the entire photogrammetric process to the finished photo or mapping product was also taken into account. The approach chosen will also maintain the usual central perspective for the new digital images.
Photogrammetric Capabilities of the Kodak DC40, DCS420 and DCS460 Digital Cameras
The Photogrammetric Record, 1999
The aim of this study is to assess the impact of sensor size and resolution of different digital camera sensors upon the accuracy and precision of three dimensional data derived by photogrammetry. Kodak DC40, DCS420 and DCS460 digital cameras were used to produce digital images of retroreflective targets in a 4 m three dimensional test field. The image locations of the targeted points were automatically measured using an off the shelf image processing software package. Two different sub-pixel measurement approaches were examined: centre of gravity and weighted mean. From the automated sub-pixel measurement of the targeted points, results indicate that the high resolution DCS460 camera produces optimum results using either the weighted mean or centre of gravity approaches. Although this was perhaps expected, the far lower resolution DC40 camera performed better than was originally anticipated, suggesting potential for the cheaper DC40 for many applications.
Design Concepts for Digital Photogrammetric Cameras
1997
Digital camera systems will gain increasing ground in various fields of application. The exacting requirements made by photogrammetry on resolution and accuracy are pushing current sensor technology to or beyond the limits of what is technically feasible today. The present paper describes and analyzes solutions based on CCD line and various area sensor configurations. Prospects and risks of digital cameras are discussed.
Photogrammetric software for the LH Systems ADS40 airborne digital sensor
International Archives of …, 2000
Airborne linear array sensors present new challenges for photogrammetric software. The push-broom nature of these sensor systems has the potential for very high quality images, but these are heavily influenced by the dynamics of the aircraft during acquisition. ...
Remote Sensing, 2009
The transition from film imaging to digital imaging in photogrammetric data capture is opening interesting possibilities for photogrammetric processes. A great advantage of digital sensors is their radiometric potential. This article presents a state-of-the-art review on the radiometric aspects of digital photogrammetric images. The analysis is based on a literature research and a questionnaire submitted to various interest groups related to the photogrammetric process. An important contribution to this paper is a characterization of the photogrammetric image acquisition and image product generation systems. The questionnaire revealed many weaknesses in current processes, but the future prospects of radiometrically quantitative photogrammetry are promising.