We use this notion for such research  methods, with which we collect data from our closer or wider environment in  such a way, that the information collector (usually called sensor) apparatus is  not in direct contat with the examined object or phenomenon. Photography is a  typical way of GIS-type data collection; the camera which is in a determined  distance from the object or phenomenon, through its lens receives the light  (electromagnetic radiation) and projects it onto a light-sensitive plate  (film), on which by chemical reactions, picture develops.(Geographic information system) 
          Aerial images 
          These photos are made with specially  designed measuring cameras for this purpose, that are attached to airplanes.  These photos can be monochrome or color, and with an appropriate evaluating  instrument we can use pictures with 3D effects in making our map. (Jesús Reyes Nunez) 
          Space images 
          Photos taken by sattelites are employed in  making maps since the 1960’s. Satellite pictures not only cover large surfaces,  but as being digital in format, they can be used and analyzed directly in GIS  systems. 
            (Jesús Reyes Nunez) 
            
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