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HISTORY OF PHOTOGRAMMETRY 
Chapter 6: ANALYTICAL METHODS AND INSTRUMENTS 
Contributing Author: Sanjib K. Ghosh 
Professor of Photogrammetry 
Laval University, Pavilion Casault 
Quebec G1K 7P4 Canada 
Tel.: (418) 656-5762 
Telex: 051-31621 UNILAVAL 
Fax: (418) 656-3177 
6.1 Introduction 
In photogrammetry the word "Analytical" has been used synonymously 
with "computational", where the solutions are obtained by mathematical 
methods as against "Analog", where solutions are obtained by analogy or 
similitude developed through optical-mechanical procedures. The backbone 
of analytical methods consists of various mathematical concepts to rep 
resent relations between points in the object, their corresponding images 
and operational procedures to solve specific problems. 
Analytical photogrammetric procedures may be considered along 
three operational stages, each involving specific instruments (see Fig. 
6.1), viz., those used for acquisition of image data (mensural), those 
used for data-processing and analyses (computational) and those used for 
display or presentation of the results. 
Fig. 6.1 
In view of the above, we would study the historical developments 
firstly with regard to the mathematical concepts and next with regard to 
the instruments and their potentials for the future. 
A mathematical model, in expressing the relevant concept, provides 
insight into the underlying chain of events. There is no mystery about 
the way in which this insight is achieved. The mathematical models have 
no scientific value unless they have been validated adequately through 
experience and research. Scientific validation is an open-ended pro 
cess. As a mathematical model is successfully tested and used, it becomes 
established. Otherwise it stands to be changed, modified or simply drop 
ped. We have witnessed this through the historical development of analyti 
cal photogrammetry. 
Furthermore, photogrammetry being an applied science, it is the 
content and not the form of the mathematical statement (language) that 
matters most. Thus we have noticed that mathematical and operational 
concepts have been adapted to circumstances without really changing the 
basi'c contents. The following sections would highlight the conceptual 
developments without going into personal details.