ALBERT

Notes: The paper describes the material generated in carrying out architectural photogrammetric surveys. The importance of the archival nature of this material is highlighted and reference is made to the indexing and storing of the records.

Notes: The problems associated with remote sensing archives arising out of the volume of data and the short life of computer compatible tapes and optical discs are touched upon. Copyright concerns are shared with owners of aerial photography.

Notes: This paper presents a critical investigation of those parts of digital mapping that relate to the specific area of terrain modelling systems. In addition, image processing and database systems are considered where they impinge on model creation or later analysis. The theoretical basis for surface mapping systems is described and an attempt is made to determine how best such systems can cover many of the practical requirements of commercial, industrial, and institutional surveyors and researchers. Some proprietary computer terrain modelling systems are mentioned where they have particular features that relate to the theme of the paper. However, most of the examples are derived from Panacea, the terrain modelling software written by the author, although in many cases any major modelling system could have been used.

Notes: Book review in this aticle:FINAL REPORT ON THE JOINT TEST ON GROSS ERROR DETECTION OF OEEPE AND ISP WG III/1. By W. Förstner.BUILDING DATABASES FOR GLOBAL SCIENCE. Edited by H. M. Mounsey. General Editor, R. F. Tomlinson.EXPLOITING REMOTELY SENSED IMAGERY. Edited by K. A. Browning, B. J. Conway, J.-P. A. L. Muller and D. J. Stanley.APPLIED PHOTOGRAPHIC OPTICS. By S. F. Ray. Focal Press, London and BostonDIGITAL IMAGE PROCESSING IN REMOTE SENSING. Edited by J.-P. Muller.AMY JOHNSON. By C. Babington Smith. Third edition.THE AEROFILMS BOOK OF BRITAIN'S RAILWAYS FROM THE AIR. By C. Leigh.SURVEYING AND MAPPING FOR FIELD SCIENTISTS. By W. Ritchie, M. Wood, R. Wright and D. Tait.SPACELAB METRIC CAMERA EXPERIMENT: TEST OF IMAGE ACCURACY. By I. J. Dowman and G. Ducher.LAND INFORMATION MANAGEMENT. By P. F. Dale and J. D. McLaughlin.KEYGUIDE TO INFORMATION SOURCES IN REMOTE SENSING. By E. C. Hyatt.

Notes: Military systems are becoming far more demanding in their requirement for geographical information. Military Survey must be able to support these requirements and consequently undertake a continuous evaluation of new potential sources and exploitation systems. In considering SPOT data, both the improved spatial resolution and the three dimensional capability afforded by the system must be investigated. Military Survey, together with universities and industry, is conducting trials on the accuracy and detail obtainable from both film and digital data. This paper will consider the three dimensional geometric fidelity of SPOT data using three different systems. The first exploits the data as a stereopair of diapositives using an analytical plotter. The second is a hybrid system in that the stereoscopic digital data are loaded into an image processing workstation which projects a stereo-image onto a split screen. This is then treated as “hardcopy” and is interactively exploited by a conventional stereoscope. The third system is completely digital in that height extraction is undertaken within a digital environment incorporating autocorrelation routines. Overall system errors of 10 m to 12 m (σ) were recorded for each exploitation system. Digital elevation model accuracies varied depending upon terrain type and image contrast.

Notes: Small format (SF) cameras, fitted to light or microlight aircraft, can provide an economic and convenient alternative to the more expensive conventional mapping systems. Further advantages accrue from the use of wider aperture lenses, an extensive range of easily available films and simplijed processing. These advantages can be exploited by employing light aircraft for small survey missions, such as map revision, and desktop photogrammetric systems dedicated to handling SF imagery. In this paper, an account is given of a research study involving SF map revision survey photography, using a modern microlight aircraft and a 70 mm metric camera.

Notes: Most normal requirements of photocontrol for mapping are outlined in terms of accuracies, patterns and densities of points, and methods of identification. An established mapping organisation is well able to make the necessary allowances for particular local difficulties.Ground control remains an expensive, high risk and time consuming part of the map production process which should be kept to a minimum by using aerial triangulation and airborne control where appropriate. Once the GPS (global positioning system) satellites become fully operational, the approach to control will have to be reassessed.

Notes: This paper was prepared as supporting documentation for a tutorial given by the authors under Photogrammetric Society auspices. The authors do not make any claims of novelty or innovation but they feel that the information contained in the paper will provide useful study material, especially for practitioners of photogrammetry and surveying. The following topics are covered: functional and stochastic models; the least squares process; statistical testing; optimal design methods; and numerical examples in the design of a horizontal control network and of a close range photogrammetric survey.

Notes: Book review in this aticle:INTRODUCTION TO THE PHYSICS AND TECHNIQUES OF REMOTE SENSING. By C. Elachi.COMPUTER PROCESSING OF REMOTELY-SENSED IMAGES. By P. M. Mather.ARCTIC AIRMEN. B E. Schofield and R. C. Nesbit.WARBURTON'S WAR. The life of Wing Commander Adrian Warburton, DSO and Bar, DFC and Two Bars, DFC (USA). By T. Spooner.MAP PROJECTIONS—A WORKING MANUAL. By. J. P. Snyder.WORLD MAPPING TODAY. By R. B. Parry and C. R. Perkins.CONTROL SURVEYS IN CIVIL ENGINEERING. By M. A. R. Cooper.INTRODUCTION TO REMOTE SENSING. By J. B. Campbell.ANALYTICAL PHOTOGRAMMETRY. By S. K. Ghosh.

Notes: Due to the inherent poor downward visibility of typical light faced wing aircraft the tracking of parallel flight lines is a problem. Various solutions have been examined and details of a remotely controlled colour video system are given.

Notes: The use of small format systems for aerial photography as an alternative to employing the more customary larger 230×230 mm format cameras continues to gain acceptance in a number of applications on the basis of the lower operating costs involved. The reduced costs and relative ease of operation with small format systems can attract unskilled operators who, by producing inferior photographic coverage, may delay the more widespread introduction of smaller systems for photo-interpretation and photogrammetric surveys of local sites. Anticipating the need for a flying and photography specification that would serve the needs of all interested parties, a series of laboratory trials were undertaken in conjunction with a literature review to quantify the comparative image quality performance of both large and small format systems. The spatial resolution of a typical small format system was assessed by photographing a low contrast resolution target using a collimator-based system and also by directly recording the target at a predetermined reduction scale. Comparative results between the two methods of evaluation are assessed and a comparison is made with the performance of larger format cameras.

Notes: The paper reviews technological developments since the Second World War and their impact as catalysts in developing the concept of digital information systems. The case for, and progress towards, the establishment of a Geographic Information System for Northern Ireland is discussed together with consideration of the possible implications elsewhere based on the experience gained in Northern Ireland.“There is a tide in the affairs of men which, taken at the flood, leads on to fortune.”Brutus in Julius Caesar, Act IV Scene iii (William Shakespeare)

Notes: Book review in this aticle:COMPUTERS AND THE REPRESENTATION OF GEOGRAPHICAL DATA. By E. E. Shiryaev.CURVE AND SURFACE FITTING: AN INTRODUCTION. By P. Lancaster and K. Šalkauskas.ACTES DU COLLOQUE FI3G.DETECTION AND CLASSIFICATION OF ICE. By E. O. Lewis, B. W. Currie and S. Haykin.CLASSIFICATION OF REMOTELY SENSED IMAGES. By I. L. Thomas, V. M. Benning and N. P. Ching.NORFOLK FROM THE AIR. Edited by P. Wade-Martins.INFLUENCES OF REPRODUCTION TECHNIQUES ON THE IDENTIFICATION OF TOPOGRAPHIC DETAILS ON ORTHOPHOTOMAPS. By Commission E (President W. Hofmann) European Organisation for Experimental Photogrammetric Research.

Notes: After a brief explanation of the role of the Directorate of Military Survey, the paper describes the production of part of a new series of 1:100 000 scale maps of Oman by soldiers of 42 Survey Engineer Group. Starting with the design and observation of the field survey control network, continuing with aerial triangulation and plotting, followed by compilation and all stages of production from drawing to printing of the maps, the project exercised the skills of survey technician soldiers to a high degree. The paper elaborates on the unusual problems caused by the barren nature of the terrain and describes the use of advanced technology during the latter part of the project.

Notes: Photogrammetric data form a major input to geographical information systems. The evolution of digital output from stereoplotters is traced, from hardwired devices producing co-ordinates or hardcopy to direct links with sophisticated GIS software. The view that the transfer and reformatting processes are simple and straightforward is examined and it is suggested that considerable labelling and structuring of data are necessary before the full power and flexibility of GISs can be harnessed. Hence it is argued that on line database creation by means of stereoplotter/GIS interfaces may not be the most cost effective procedure.

Notes: The development and operation of a remote control system for a camera rig and for the camera attached to it are described. Now there is the possibility of reducing the crew from three to two for many tasks and to use the extra payload to collect contemporaneous data using a second airborne system.

Notes: Book reviewed in this aticle:AERIAL PHOTO-INTERPRETATION IN TERRAIN ANALYSIS AND GEOMORPHOLOGIC MAPPING. By R. A. van Zuidam.REMOTE SENSING: METHODS AND APPLICATIONS. By R. M. Hord.FRENCH-ENGLISH GLOSSARY ON SPOT, REMOTE SENSING AND THEIR APPLICATIONS. By S. T. Dyson.REMOTE SENSING. PRINCIPLES AND INTERPRETATION. Second Edition. By F. F. Sabins.APPLIED REMOTE SENSING. By C. P. Lo.HISTORY OF CARTOGRAPHY. By L. Bagrow.REMOTE SENSING YEARBOOK 1987. Edited b A. P. Cracknell and L. W. B. Hayes.WINGS OVER ICE. By P. G. Mott.MANUAL OF AERIAL PHOTOGRAPHY. By R. W. Graham and R. E. Read.

Notes: Following a period of considerable debate and change in the organisation of the Ordnance Survey, the use of photogrammetric methods and equipment in the support of its mapping tasks during the period 1972–1986 is reviewed.

Notes: Since 1960, photogrammetry has played a leading role in the acquisition of survey data within the Ordnance Survey of Northern Ireland. The decision to create a digital topographic database for Northern Ireland has changed the philosophy and practice of photogrammetry within the organisation and these changes are discussed in this paper.

Notes: A new lightweight vertical camera rig which can be clamped to the front legs of the front seat of a light aircraft is described. In one version, a fixed transparent fairing is attached to the door, whereas in the second version the fairing is attached to the camera rig itself which can then be extended and retracted in flight. This rig has received C.A.A. (Civil Aviation Authority) Approval.

Notes: SPOT-1, launched on 22nd February, 1986, has provided the first opportunity to produce topographic maps from space on an operational basis. The use of SPOT imagery can be justified because of reduced costs and reduced lead times for map production. However SPOT imagery cannot be handled in the same way as conventional photography and it requires new procedures to be adopted, The two main reasons for this are the large area covered by each image and the dynamic form of sensing. The procedures discussed in this paper have been implemented in a working system for map compilation.

Notes: The authors provide an account of current Directorate of Military Survey approaches to the provision of photocontrol by use of GPS and they pay special attention to the requirements of height control. 〈section xml:id="abs1-2"〉〈title type="main"〉SummaryGPS now provides us with a rapid method for determining plan and height for photogrammetric control directly over the points required by the photogrammetrist. By utilizing the slope of the geoid model, orthometric heights can be obtained to an accuracy of 0.15 m to 0.2 m. Surveys can be carried out quickly in all weather conditions and with none of the traditional terrestrial survey skills. Time, cost and manpower are greatly reduced. The plan accuracies are well within any requirements of the photogrammetrist and heights can be achieved to within 0.15 m to 0.2 m on test areas of UK. As photogrammetric height accuracy requires at best 1 m for plotting a 10 metre contour interval, heighting by GPS and the use of a geoid model solves the heighting problem.〈section xml:id="abs1-3"〉〈title type="main"〉Résumé Les auteurs fournissent un compte-rendu de la façon dont le Directorate of Military Survey aborde actuellement le problème de la fourniture de points ďappui photos avec ľemploi du GPS et prêterit une attention particulière à celui des points ďappui altimétriques.〈section xml:id="abs1-4"〉〈title type="main"〉Zusammenfassung Die Autoren geben einen Bericht über die gegenwärtigen Versuche beim Directorate of Military Survey zur Paβpunktbestimmung mit GPS, wobei sie den Anforderungen an die Höhenbestimmung besondere Aufmerksamkeit zollen.

Notes: The operational situation of precise airborne GPS positioning of camera air stations and its use in combined block adjustment for aerial triangulation is reviewed. The acceptance of systematic GPS errors, which occur especially with biased phase ambiguity solutions after loss of lock of signals in-flight, has motivated the method of additional linear GPS drift parameters which are to be solved in the combined block adjustment. It also implies that no absolute GPS co-ordinates are required and that the datum transformation is provided via a few ground control points. A great number of practical examples demonstrates that the method has been successfully applied within a wide range of photoscales and of block sizes. It has proved to be fully operational under various practical conditions. The high accuracy performance of GPS blocks and the economic benefit have been confirmed. It is particularly noticeable that the stationary receiver can be at a great distance, up to 500 km or more from the mission area. The conclusion is drawn that GPS supported aerial triangulation is ready to become standard. The potential improvement from dual frequency receivers and fast ambiguity solutions only enhances that conclusion. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On examine, dans cet article, le degréďopérationnalité atteint par le GPS aéroporté dans le positionnement précis des sommets de prises de vues des caméras aériennes, et son insertion dans la compensation par blocs en aérotriangulation. La possibilityéďerreurs systématiques dans le GPS, en particulier en cas de perte des signaux en vol, qui se manifeste par des ambiguïtés de phase et des biais dans les résultats, à conduit a introduire dans la compensation en bloc des inconnues supplémental s, traduisant une dérive linéaire du GPS. II en résulte qu'il n'est pas nécessaire de disposer de coordonnées GPS absolues et que quelques points ďappui sur le terrain suffisent à assurer les changements de coordonnées. On a utilisé avec succès cette méthode dans de nombreux essaispratiques comportant un large eventail ďéchelles de prises de vues et de tallies des blocs. On a pu ainsi mettre en évidence ľentière opérationnalité de cette méthode, dans des conditions réelles différentes. On a également confirmé la haute précision des résultats des blocs GPS et les avantages économiques de ce système. En particulier, il est tout à fait remarquable que le récepteur fixe puisse se trouver à une grande distance de la zone du lasé, 500 km ou plus. On peut en conclure que ľaérotriangulation appuyée sur le GPS est en train de devenir une méthode standard. Les améliorations possibles que peuvent apporter les récepteurs à deux fréquences et la résolution rapide des ambiguïtés, ne font que renforcer cette conclusion. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Die hochgenaue Kamera Positionierung durch GPS und ihre Anwendung für die Aerotriangulation wird zusammengefaβt dargestellt. Die Existenz systematischer GPS Fehler, wie sie inbesondere durch nur genäherte Phasen-Mehrdeutigkeitslösungen nach Signalabrissen im Flug verursacht werden, haben zu der speziellen Methode zusätzlicher linearer GPS Drift Parameter geführt, die in der kombinierten Blockausgleichung bestimmt werden. Ferner wird dabei die Datumtransformation mit Hilfe einiger weniger Paβpunkte bestimmt, d.h. es werden keine absoluten GPS Koordinaten vorausgesetzt. Mit einer groβen Zahl praktischer Beispiele wird demonstriert, daβ die Methode in einem groβen Bereich von Bildmaβstäben und Blockgröβen bereits erfolgreich angewendet wird. Sie hat sich unter den verschiedensten praktischen Bedingungen als voll operationell erwiesen. Dabei wurde die theoretisch erwartete hohe Genauigkeit der GPS Blöcke und ihre Wirtschaftlichkeit bestätigt. Besonders bedeutsam ist der empirische Nachweis, daβ der stationäre GPS Empfänger sehr weit, bis 500 km oder mehr, von dem Fluggebiet entfernt sein kann. Als Ergebnis wird empfohlen, die GPS gestützte Aerotriangulation als verfügbares photogrammetrisches Standardverfahren allgemein zu verwenden. Diese Schluβfolgerung wird durch die neuesten Entwicklungen von Zwei-Frequenz Empfängern und schnellen Mehrdeutigkeitslösungen, in die hohe Erwartungen gesetzt werden, nur noch bekräftigt.

Notes: Photogrammetrists are acutely aware that remote methods of survey are commonplace. However, it is only relatively recently that high precision levelling of the national motorway network has been conducted in this manner. There are now several competing methods available, all of which have gained some acceptance. This paper describes a low level aerial photographic method employing a helicopter as the platform. It begins with the reasons for the development, describes the system and methods involved, addresses the safety aspects, attempts to outline the necessity for the largest scale possible to maintain precision, analyses the potential developments and discusses the advantages and disadvantages compared with ground based systems.

Notes: Using modern techniques, the analysis of amateur photographs yields results with almost the same accuracy level as with metric photographs. This paper gives a classification of data processing techniques for amateur photographs and presents a well proven method for the treatment of existing amateur photographs, known as Metric Photo Perspective Transformation (MPPT). Data processing is particularly convenient and efficient if on line techniques are used. Operational procedures for the treatment of additional parameters and for the detection of blunders in a time critical on line triangulation system are proposed.

Notes: Rigorous photogrammetric methods have been used to carry out a detailed evaluation of Metric Camera panchromatic photographs of two areas, one in south-east France and the other on the coast of Libya. Inner, relative and absolute orientation and space resection were performed in order to determine how accurately ground co-ordinates can be obtained and the most suitable scale for mapping. Results of absolute orientation (residuals of 19m in plan and 26m in height) indicate that it is possible to produce maps at 1:100000 scale with contours at 100m intervals. Plotting has been done at 1:100000 scale showing cultural and drainage features. It was not possible to identify all detail which is plotted on existing 1:100000 scale line maps.

Notes: This paper discusses an inexpensive, analytical system designed for a forestry application of photogrammetry. It is presented in two parts. Part I describes an image space plotter that was built in New Zealand and is operating there. The system uses a digitising table to collect left-hand photograph co-ordinates. an encoded micrometer bar to measure × parallax and a mirror stereoscope for viewing photographs. The mathematical, formulation is based on simplifications first suggested by E. H. Thompson. Good accuracy in ground heights can be achieved by the system, but only poor accuracy in planimetric co-ordinates. The cause of poor planimetric accuracy is investigated in Part II. Two error sources are apparent: the simplified analytical theory and systematic errors from the digitising table. Part II also investigates the relationship between random errors in image co-ordinate measurements and system accuracy.

Notes: Underwater photogrammetry is being used in the particularly hostile environment of the North Sea where it has been put into commercially viable operation. The authors discuss underwater photogrammetry related to other means of inspection of oil platforms. They also deal with operational experience of 35 mm and 70 mm cameras, camera calibration, the provision of control and photogrammetric observations and data analysis. The demand for underwater photogrammetry continues to grow.

Notes: The application of phorogrammetry to the measurement of deformation is discussed and four different approaches are identified and compared. References to and summaries of recent work are made.

Notes: The development and operation of an inexpensive retractable vertical camera rig is described. Unlike several commercially available camera packages, the cameras on this rig are accesible in flight thus permitting the changing of magazines and other operations. Since the camera carriage is only deployed when over the site to be photographed, the aircraft performance is not degraded during positioning flights.

Notes: This paper summarises the theoretical and practical development of’an analytical system for close range photogrammetry. The system uses the extended bundle method of phototriangulation and a sophisticated least squares algorithm. A description is given of computer software, and aspects of statistical testing and gross error detection are discussed in order to assess the accuracy potential. Applications of the system, for precise co-ordination of a target range and camera calibration are outlined.

Notes: A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed.

Notes: This paper reviews the growth in the use of photogrammetric techniques in architecture, principally in the United Kingdom, over the past ten years. The work of the various establishments involved in architectural photogrammetry is described and the results of a questionnaire, distributed within the architectural profession, are analysed. Some comparisons are made with developments elsewhere in Europe.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn examine dans cet article l'extension qu'a connue l'utilisation des méthodes photogrammétriques en architecture au cows des dix dernières années, principalement dans le Royaume-Uni. On y décrit les travaux des divers organismes impliqués dans la photogrammétrie architecturale et l'on y analyse les résultats d'un questionnaire diffusé au sein de la profession liée à l'architecture. On fournit enfin quelques comparaisons avec les développements constatés par ailleurs en Europe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird über die zunehmende Anwendung photogrammetrischer Verfahren während der letzten 10 Jahre in der Architektur, insbesondere im Vereinigten Königreich, berichtet. Die Arbeit verschiedener Institutionen, die sich mit Architekturphotogrammetrie befassen, wird beschrieben, und es werden die Ergebnisse eines unter Architekten verteilten Fragebogens analysiert. Weiterhin werden Vergleiche zu Entwicklungen in anderen europäischen Ländern gezogen.

Notes: The sixth biennial symposium of the Photogrammetric Society was held at the University of Birmingham from 26th to 28th March, 1982. The formal sessions considered four main topics, which were the work of the European Organisation for Experimental Photogrammetric Research (OEEPE), map revision, synthetic aperture radar and the use of minicomputers and digital techniques in photogrammetry. Sixteen papers were given at the symposium but the publication of some of them will occur in a subsequent issue of The Photogrammetric Record.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Le 6e symposium biennal de la Société britannique de photogrammétrie s'est déroulé du 26 au 28 mars 1982, à l'Université de Birmingham. Les réunions plénierès étaient organisées autour de quatre thèmes principaux, comprenant les travaux de l'Organisation Européenne d'Etudes Photogrémmitriques Expérimentales (OEEPE), la révision des cartes, le radar à ouverture synthétique et l'emploi des mini-ordinateurs et des techniques numériques en photogrammétrie. Seize communications y ont été priséntées, dont certaines ne seront publicées dans la revue The Photogrammetric Record que dans un numéro ultérieur.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Das 6. im Abstand von 2 Jahren veranstaltete Symposium der Britischen Photogrammetrischen Gesellschaft fand vom 26. bis 28.3.1982 an der Universität Birmingham statt. In den Vortragsveranstaltungen wurden 4 Hauptthemen behandelt, und zwar die Arbeit der Europäischen Organisation für Experimentelle Photogrammetrische Forschungen (OEEPE), die Laufendhaltung von Karten, Radaraufnahmen mit synthetischer Apertur und die Anwendung von Kleinrechnern und digitalen Verfahren in der Photogrammetrie. Es wurden dazu 16 Beiträge gehalten, wobei einige erst in einem späteren Heft des Photogrammetric Record publiziert werden.

Notes: The algorithm presented assumes a preliminary determination of the elements of inner orientation and bases its mathematical model on the collinearity condition, from which projective equations are derived. Linearisation of condition equations is based on Taylor's expansion, whilst the subsequent solution follows iteration cycles. The method aims to derive composite corrections to image coordinates, with the aid of test field data.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'auteur présente un algorithme oú l'on suppose déterminés au préalable les éléments d'orientation interne. La modélisation mathématique s'appuie sur les conditions de co-linéarité et sur les équations qui en résultent en projection. On linéarise les équations de conditions en utilisant un développement en série de Taylor, et l'on obtient la solution correspondante par itération. La méthode vise à apporter des corrections aux coordonnées images en utilisant les données d'un polygone d'essai.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei dem dargestellten Algorithmus wird die vorläufige Bestimmung der Elemente der inneren Orientierung angenommen, und das mathematische Modell basiert aufder Kollinearitätsgleichung, woraus perspektive Gleichungen abgeleitet werden. Die Linearisierung der Bedingungsgleichungen erfolgt durch Anwendung der Taylor-Reihe, was für die folgenden Berechnungen einen iterativen Prozess bedingt. Mit der Methode wird angestrebt, Bildkoordinaten mit Hilfe von Testfelddaten zu verbessern.

Notes: This paper is concerned with a new technique (the terrestrial/photogrammetric (TP) technique) for the detection and compensation of systematic height errors in block aerial triangulation. The technique improves the height accuracy of such triangulation by reducing the original bridging distance, using new bands of corrected photogrammetric tie points as height control together with the original bands of the terrestrial (or ground) height control. A number of photogrammetric blocks with different characteristics and configurations have been tested in a comprehensive manner. The tests show that the TP technique gives consistent results over a wide range of circumstances and that it is a most effective, simple and inexpensive method for the compensation of systematic errors.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméCet article relate une technique nouvelle permettant de détecter et de compenser les erreurs altimétriques systématiques dans l'aérotriangulation par blocs: la technique terrestre/photogrammétrique (TP). Cette technique améliore la précision altimétrique de l'aérotriangulation en réduisant la distance de l'aérocheminement original, grâce à l'utilisation d'un canevas de points d'appuis altimétriques composés de points de liaison photogrammétriques corrigés, en supplément du canevas original de points d'appui altimétriques déterminés sur le terrain.On a essayé de manière approfondie un grand nombre de blocs dotés de caractéristiques et de configurations diverses. Les essais montrent que la technique TP fournit des résultats fiables dans un large éventail de circonstances et que c'est une méthode de compensation des erreurs systématiques efficace, simple et peu coûteuse.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird ein neues Verfahren behandelt (das terrestrisch-photogrammetrische Verfahren (TP)), das zur Aufdeckung und Kompensation system-atischer Höhenfehler in der Block triangulation dient. Es wird die Höhengenauigkeit durch Verkürzung der ursprünglichen Überbrückungsdistanz verbessert, indem neue Streifen korrigierter Verbindungspunkte als Höhenpasspunkte zusammen mit den ursprünglichen Reihen der terrestrischen Höhenpasspunkte verwendet werden. Eine Anzahl photogrammetrischer Blöcke unterschiedlicher Figur und Charakteristik wurde umfassend getestet. Die Tests zeigen, dass die TP-Methode konstante Ergebnisse für einen grossen Bereich van Möglichkeiten ergibt und dass es ein höchst effektives, einfaches und billiges Verfahren zur Eliminierung systematischer Fehler ist.

Notes: The development of an automated photographic measuring system (APM) is described. A very accurate laser beam scanning microdensitometer is used to digitise the photographic plate and a series of on line computers analyses the data during scanning. The system is available as a national facility for United Kingdom astronomers and guest investigators.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un systéme automatisé de saisie de données sur cliché. Un microdensitométre à laser numérise la plaque photographique et les données sont analysées en temps réel par ordinateur. Le systeme est destiné aux astronomes du Royaume Uni et aux chercheurs y séjournant.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatisierten photographischen Messsystems (APM). Ein hochgenaues Laser-Mikrodensitometer wird dabei zur Digitalisierung der Bilder benutzt, undeine Serie von On-line-Rechnern analysiert die Daten während der Abtastung. Das System steht für Astronomen im Vereinigten Königreich und anderen Forschern zur Verfügung.

Notes: An automatic plotting instrument development is described where the coordinate corrections are introduced in the optical system and not at the photograph. It is suggested that the opto-mechanical devices used for correction and the proposed use of microprocessors for control of these devices offer the possibility of producing a low cost automatic plotter and stereocomparator.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn decrit une solution au probléme de la correction des coordonnées cliché pour le restituteur analytique et le stéréocomparateur: ces corrections sont introduites dans la partie optique du système et commandées par l'intermédiaire de microprocesseurs. Ceci devrait permettre d'abaisser le coût de ce type d'appareil.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatischen Auswertegerätes, bei dem die Koordinatenkorrekturen nicht den Bildträgern, sondern dem optischen System zugeführt werden. Es wird angenommen, dass die zur Korrektur verwendeten optisch-mechanischen Vorrichtungen und die vorgeschlagene Verwendung von Mikroprozessoren zu deren Steuerung die Möglichkeit zum Bau eines billigen automatischen Auswertegerätes und Stereokomparators bieten.

Notes: The method of variation of co-ordinates has been successfully applied to analytical radial triangulation. The mathematical theory and experimental results are presented in this paper. The method can be adapted to avoid the locating of conjugate principal points.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn a appliqué la méthode des variations des coordonnées à la triangulation analytique radiale. On donne les équations et les résultats des tests.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie Variation von Koordinaten wird erfolgreich für die Methode der numerischen Radialtriangulation angewendet. Es werden die mathematischen Gleichungen und die Testergebnisse angegeben. Die Methode kann auch angewendet werden, um die Anordnung konjugierter Hauptpunkte zu vermeiden.

Notes: Vertical aerial photography taken on an experimental thin base film has been tested photogrammetrically and accuracies of measurement of the order of 1/10 000th part of the flying height have been obtained. This paper outlines the handling characteristics of the film, describes the test and gives the results.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn a testé des clichés aériens pris sur films à support mince et obtenu des exactitudes de l'ordre du 1: 10000 de la hauteur de vol. Caractéristiques du film et résultats des tests.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei Luftbildern, die auf einer experimentell dünnen Filmbasis aufgenommen wurden, konnte durch photogrammetrische Tests eine Höhengenauigkeit von 0,1‰ der Flughöhe erreicht werden. Im Artikel werden die Verarbeitungsvorschriften des Films, der Test und die erreichten Ergebnisse beschrieben.

Notes: It has been recognised for many years that photographic methods of traffic data collection can overcome many of the problems associated with more traditional methods, particularly with regard to the substantial reduction in manpower requirements achieved, the comprehensive nature of the data which may be obtained and the permanent record provided of these data. Against these advantages, the major drawbacks are the expense involved in obtaining suitable photographic coverage and the time consuming operation of collecting the data from the photography.The problems of obtaining photographic coverage have been considered in an earlier paper (Garner and Mountain, 1978a) and recommendations made regarding the most suitable type of photography for analysis of traffic flow data at complex urban and suburban intersections. This paper concentrates, therefore, on the second problem, namely that of extracting the required data from the photographs. The technique described involves the use of a co-ordinate reader to obtain the two dimensional co-ordinates of vehicles on successive frames, a coordinate transformation system to convert photographic co-ordinates to ground coordinates and, finally, a computer based co-ordinate matching technique.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn sait depuis plusieurs années que l'application de la photogrammétrie aux études sur la circulation urbaine, peut être fort avantageuse: réduction de personnel, diversité des données obtenues, actualisation facile des fichiers. Un obstacle à leur diffusion cependant: le coût de la prise de vue et la lenteur de l'extraction des données.Le problème de la prise de vue a déjà donné lieu à un article (Garner et Mountain, 1978a). Celui-ci décrit des méthodes d'exploitation: on use d'un lecteur de coordonnées pour mesurer les coordonnées bi-dimensionnelles des véhicules sur les clichés et d'une transformation menant à un système cartographique.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungSeit vielen Jahren ist bekannt, dassfotografische Verfahren zur Erfassung von Verkehrsdaten rationeller sind als traditionelle Methoden, insbesondere was die Einsparung an Arbeitszeit, die Datendichte und die kontinuierliche Aufzeichnung betrifft. Dagegen sprechen die erhöhten Kostenfür die fotografische Aufnahme und die zeitaufwendige Datenentanahme aus Bildern.Die Probleme der fotografischen Aufnahme wurden bereits früher erörtert (Garner und Mountain, 1978a), und es wurden Empfehlungen für den günstigsten Aufnahmefall zur Analyse des Verkehrsflusses an komplexen Kreuzungen in Städten bzw. Vorortengegeben. Die vorliegende Arbeit konzentriert sich daher auf das 2. Problem, die Gewinnung der geforderten Daten aus Fotos. Die beschriebene Technologie umfasst die Verwendung einer Koordinatenablesevonichtung zur Ermittlung der zweidimensionalen Koordinaten von Fahrzeugen auf aufeinanderfolgenden Bildern, ein Transformationssystem zur Umwandlung von Bild- in Geländekoordinaten und ein rechnergestütztes Aufzeichnungsverfahren.

Notes: Book Reviewed in this article:AERIAL PHOTOGRAPHY. By G. S. Kumar.MANUAL OF PHOTOGRAMMETRY (Fourth Edition). Editor-in-Chief: C. C. Slama.

Notes: Two complementary measuring instruments are described which use a very simple principle and which take three dimensional measurements or plots directly from small objects. The first instrument can achieve accuracies of ± 0·3 mm on objects whose largest dimension is 300 mm. The second can achieve ± 0·02 mm on objects smaller than a 25 mm cube.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn présente deux instruments de mesure complémentaires el de principe très simple permettant de relever dans l'espace des coordonnées sur de petits objets, le premier avec une exactitude de ± 0.3 mm sur des objets de dimension inférieure à 300 mm, le second avec une exactitude de ± 0.02 mm sur des objets de dimension inférieure à 25 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung von zwei Zusatzmessgeräten, die auf einem sehr einfachen Prinzip beruhen und mit denen dreidimensionale Messungen oder Auswertungen von kleinen Objekten direkt durchgeführt werden konnen. Mil dem ersten Gerät kann eine Genauigkeit von ± 0,3 mm bei maximalen Objekt abmessungen von 300 mm und mit dem zweiten von ± 0,02 mm bein Objekten, die kleiner als ein 25 mm-Kubus sind, erreicht werden.

Notes: This paper describes a system for the interior, relative and absolute orientations of steroplotter models, using a minicomputer interfaced to the plotter as an aid to the operator. Both aerial and terrestrial models were included in the evaluation of the system but the emphasis is on close range work where significant improvements in efficiency and precision can be obtained.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un système d'aide à la restitution (orientation relative et orientation absolue) utilisant un mini-ordinateur relié par une interface à l'appareil de restitution. II vaut tant pour les couples terrestres que les couples aériens; on a cependant accordé une attention spéciale au cas de la photogrammétrie à courte distance oú certaines dispositions permettent un gain significatif d'exactitude.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIn dem Artikel wird ein System zur inneren, relativen und absoluten Orientierung von Stereomodellen unter Benutzung eines Minirechners beschrieben, der zur Unterstützung des Auswerters an das Stereokartiergerät angeschlossen ist. Obwohl bei der Analyse des Systems sowohl Luftbilder als auch terrestrische Bilder betrachtet werden, liegt das Schwergewicht auf der Nahphotogrammetrie, wo dadurch bedeutende Verbesserungen in bezug auf Leistungsfähigkeit und Genauigkeit erhalt en werden können.

Notes: In 1989, the Council of the Photogrammetric Society decided that some record of the use of analogue photogrammetric equipment in Great Britain should be preserved before it was too late. The author agreed to investigate this matter as a research project funded by a number of survey organisations. Work on the project so far has resulted in the completion of two documents. The first is a Catalogue of Analogue Instruments that list some 230 instruments of 30 different types. The second is an Archive that gives further details of the history and use of the 30 different types of instrument. The entry included in his paper, by way of example, is that concerned with the Zeiss Stereoplanigraph.Readers are encouraged to provide corrections and additional information wherever possible.

Notes: Developments in automated close range photogrammetry over the past decade have produced systems capable of achieving measurement accuracies of one part in several hundred thousand of the size of the object. The impetus for precision photogrammetry has come mainly from the industrial sectors of aircraft, aerospace and antenna manufacturing, but potential applications are not limited to these areas alone. This paper discusses the applicability of industrial photogrammetric techniques for the monitoring of ground surface displacements which accompany oil recovery operations. A pilot study is reported in which photogrammetric positioning accuracies at the millimetre level were sought over an area of 1 × 1.6 km. The large scale of the convergent network, coupled with the high level of positioning accuracy, meant that special consideration had to be given to both operational aspects (helicopter photography and targeting) and mathematical modelling (refraction compensation). Lessons learned in this project have implications for the broader application of high precision photogrammetry in large scale civil and geotechnical engineering, as well as in the mining industry. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Les progrès réalisés dans la photogrammétrie rapprochée automatisée au cours de la dernière décennie, ont débouché sur des systèmes capables ďeffectuer des mesures avec une précision de quelques cent millièmes de la taille de ľobjet. La photogrammétrie de haute précision a bénéficiéďune impulsion venant essentiellement du secteur des industries de ľaviation, de ľaerospatial et des constructeurs ďantennes, mais ses applications potentielles ne se limitent pas à ces seuls secteurs. On examine dans cet article la possibilityéďapplication des techniques de photogrammétrie industrielle à la surveillance des mouvements de la surface du sol qui se produisent dans les opérations ďextraction du pétrole. On décrit une opération-pilote dans laquelle on recherchait des précisions de localisation photogrammétrique de ľordre du millimètre sur une zone de 1 × 1,6km. La réalisation ďun réseau de photographies convergentes prises à grande échelle et destinées à fournir une précision de localisation de haut niveau, a demandé de prêter une attention particulière aux aspects opérationnels (photographie en hélicoptère et pré-balisage) ainsi qu'à la modélisation mathématique (corrections de réfraction). Ľexpérience acquise dans ce projet pourra être utilisée pour une application plus étendue de la photogrammétrie de haute précision dans le domaine du génie civil ou géo-technique à grande échelle ainsi que dans ľindustrie minière. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Entwicklungen in der automatisierten Nahbereichsphotogrammetrie haben in der letzten Dekade zu Sstemen geführt, mit denen Meβgenauigkeiten von 1 zu einigen Einhunderttausend der Objektgröβe möglich sind. Der Anstoβ zur Präzisionsphotogrammetrie kam hauptsdchlich von der Luftfahrt-, Raumfahrt- und Antennenindustrie, aber mögliche Anwendungen sind nicht darauf beschränkt. Im Artikel wird die Anwendbarkeit von Verfahren der Industriephotogrammetrie auf Bewegungen der Gelände-oberfläche, die im Zusammenhang mit der Förderung von Erdöl auftreten, diskutiert. Es wird über eine Pilotstudie berichtet, bei der man über ein Gebiet von 1x1,6 km photogrammetrische Positioniergenauigkeiten im Millimeter-Bereich anstrebte. Der groβe maβstab des konvergenten Netzes, gepaart mit dem hohen Niveau der Positioniergenauigkeit bedeuteten, daβ sowohl die operationellen Aspekte (Hubschrauberaufnahmen und Signalisierung) ah auch die mathematische Modellierung (Kompensation der Refraktion) spezielle Überlegungen erforderten. Die bei diesem Projekt gesammelten Erfahrungen haben einen Einfluβ auf die breitere Anwendung der Präzisions-photogrammetrie auf groβmaβstäbige Aufgaben im Bau- und Geo-ingenieurwesen sowie im Bergbau.

Notes: In 1987, the Scottish Office commissioned vertical aerial photography for the whole of Scotland at 1:24 000 scale. The paper describes the need for this national coverage, the physical and economic constraints and the acquisition of the photographs. The principal use of the photography, as a database for measuring land cover change in Scotland, is summarised and numerous other projects are also described. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Le Bureau des Affaires Écossaises a commandé en 1987 une couverture photographique aérienne verticale au 1:24000 sur ľensemble de ľÉcosse. On présente dans cet article les besoins qui ont motivé cette couverture, les contraintes économiques el physiques correspondantes et le déroulement de sa saisie. On donne un aperçu de la principale utilisation de ces photographies, destiniées à constituter une base de données pour la détermination des modifications intervenues en Écosse dans ľoccupation du sol; de nombreux autres projets sont également mentionées. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Im Jahre 1987 gab das Scottish Office Auftrag zur Luftbildaufnahme im Maβstab 1:24000 von ganz Schottland. Im Artikel werden die Notwendigkeit für diese vollständige nationale Bedeckung, für die physikalischen und ökonomischen Zwangsbedingungen und für die Beschaffung der Fotos beschrieben. Die prinzipielle Nutzung der Fotografie als Datenbasis zur Bestimmung der Landnutzungsänderung in Schottland wird hervorgehoben und zahlreiche andere Projekte werden ebenso beschrieben.

Notes: Fully digital photogrammetric close range systems allow for on line or even real time processing of data. This gives access to a great number of new applications, especially in those cases where a moving object has to be dynamically recorded or a moving sensor has to be positioned and oriented in three dimensional space, as is the case in robotics. This article gives a brief survey of the problems and potential of these new systems and techniques. Aspects of fast data acquisition and processing are addressed and a concise description of the DIPS II digital station is provided. The accuracy of digital systems is reviewed and two significant new algorithmic developments are referenced. Finally, three characteristic projects demonstrate the potential and performance of digital close range photogrammetry. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Les systèmes utilisés en photogrammétrie à courte distance permettent, lorsqu'ils sont entièrement numériques, un traitement en ligne des donnés, et même en temps réel. Cela ouvre la voie à un grand nombre ďapplications nouvelles, particulièrement lorsqu'il s'agit ďun objet mobile qu'il faut enregistrer dynamiquement ou ďun capteur mobile qu'il faut localiser et orienter dans un espace à trois dimensions, comme c'est lecas en robotique. On examine brièvement dans cet article les problèmes et les possibilityés de ces nouvelles techniques et de ces nouveaux systèmes. On aborde quelques aspects concernant la saisie et le traitement rapide des donnés et ľonfournit une brève description du poste numérique DIPS II. On analyse la précision des sytémes numériques et ľon mentionne deux nouveaux développements algorithmiques importants. Enfin on illustre les possibilityés de la photogrammétrie numérique à courte distance et les résultats atteints, en s'appuyant sur trois projets typiques. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Vollständig digitale Systeme in der Nahbereichsphotogrammetrie gestatten die On-line-oder sogar Echtzeitdatenverarbeitung. Das ermöglicht eine groβe Anzahl neuer Anwendungen, besonders in solchen Fällen, wo ein bewegtes Objekt dynamisch registriert oder ein bewegter Sensor im dreidimensionalen Raum positioniert und orientiert werden soil, z.B. im Falle von Robotern. Im Artikel wird eine kurze Übersicht über die Probleme und die Möglichkeiten dieser neuen Systeme und Verfahren gegeben. Aspekte der schnellen Datenerfassung und -verarbeitung werden angesprochen, und es erfolgt eine knappe Beschreibung der digitalen Arbeitsstation DIPS II. Die Genauigkeit digitaler Systeme wird analysiert und zwei signifikant neue algorithmische Entwicklungen werden zitiert. Abschlieβend demonstrieren drei charackteristische Projekte die Möglichkeiten und Leistungsfähigkeit der digitalen Nahbereichsphotogrammetrie.

Notes: Hertfordshire County Council makes extensive use of aerial photography obtained from the ten yearly air survey of the entire county. This paper emphasises the value of the photography for specialist applications in the Planning and Estates Department, but also considers other uses. Details are given of photographic products and of a land use survey based on photo-interpretation. Finally, the future policy on the commissioning of aerial photography for Hertfordshire is considered, taking into account the potential of satellite imagery, the requirements of the existing GIS system for association with aerial photography and the possibility of additional revenue from more assertive marketing of photographic products. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Le Conseil du Comté de Hertfordshire se sert considérablement des photographies aériennes obtenues dans le cadre du levé aérien décennal de tout le comté. On souligne dans cet article ľintérét que trouvent, dans ces photographies, les spécialistes du Ministère de ľAménagement et ľon examine également ďautres utilisations. On fournit des détails sur les produits photographiques et sur un levéďusage du sol obtenu à partir ďune photo-interpretation. Enfin on examine la politique envisagée àľavenir pour ľexécution de la couverture aérienne de ľHertfordshire, qui prendre en compte les possibilityés de ľimagerie spatiale, les besoins ďintégration de la photographie aérienne dans les SIG actuels, et les revenus supplémentaires qui devraient provenir ďune démande commerciale plus soutenue sur les produits photographiques. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Der Hertfordshire County Council macht regen Gebrauch von Luft-bildern, die vor 10 Jarhen von der ganzen Grafschaft aufgenommen wurden. In dem Beitrag wird der Wert der Bilder für die Nutzung durch Spezialisten bei der Planning and Estates Department betont, aber est werden auch andere Anwendungen betrachtet. Es werden Details über fotografische Erzeugnisse und tiber eine auf der Photointerpretation basierende Land-nutzungserhebung angegeben. Schlieβlich wird die künftige Politik bei Aufträgen zur Luftbildaufnahme für Hertfordshire dargelegt, wobei das Potential von Satellitenbildern, die Anforderungen des bestehenden GISzur Verbindung mil Luftbildern und die Möglichkeit zusätzlicher Einnahmen dureh gröβere Vermarktung fotografischer Erzeugnisse in Betracht gezogen werden.

Notes: The authors describe and illustrate the successful provision of a survey /light navigation and camera control system which is based on reception of GPS signals in the survey aircraft, linked to an onboard computer. 〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Les auteurs décrivent et illustrent la mise en æuvre réussie ďun système de navigation aérienne et de commande de la chambre de levés photographiques, basé sur la réception des signaux GPS dans ľavion photographe avec connexion àľordinateur de bord. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Die Autoren beschreiben und veranschaulichen die erfolgreiche Installierung eines Systems zur Navigation des Bildflugs und Steuerung der Luftbildmeβkammer, das auf dem Empfang von GPS-Signalen und ihrer Verbindung mit einem Bordrechner des Bildflugzeugs basiert.