Category talk:01 Introduction to remote sensing
The term "remote sensing" was first used in the 1960s when space technology, construction of computers, storage and photosensitve sensor elements made considerable progress. The beginning of the early history of remote sensing can be dated much earlier at the invention of photography by Niepce, Daguerre and Talbot and the first photo taken from a hot air balloon by Tournachon in 1858.
In many textbooks, remote sensing is defined as "measuring without being in direct contact with the object of interest". More preciseley, the term "sensing" is directly related to the human sensory system of vision. We may understand the natural principle of human vision and recognition as a protoype for designing a technology for information retrieval by measuring variations of electromagnetic radiation. The function of human eyes consisting of lenses and photosensitive rods and cones of the retina are applied in photography as cameras composed of objective lenses, analogue film emulsions or CCD sensor elements.
The term "remote" is related to applications of distant vision from an elevated point similar to a bird's view flying and observing the landscape from above. Thus, close-range photogrammetry and terrestrial laser scanning are not in focus but can be seen as early stages of remote sensor development before mounting on manned (e.g. aircraft) or unmanned (e.g. satellite) platforms.
A general definiton:
- remote sensing is the science and technology of information retrieval on substances and objects by measuring electromagnetic radiation from elevated platforms.