GEOG 2195 Lecture Notes - Lecture 6: Photographic Film, Computer Cluster, Spectral Signature
Document Summary
Data in the form of images are collected from a distance which are a representation of the amount of emr reflected or emitted by objects on the surface of the earth providing a systematic collection of geographic information. Electromagnetic energy can be detected photographically or electronically. The photographic process uses chemical reactions on the surface of light-sensitive film to detect and record energy variations. Photograph: specifically images that have been detected as well as recorded on photographic film. Image: any pictorial representation, regardless of what wavelengths or rs devie used to detect and record the electromagnetic energy. Thus photographs are images but not all images are photographs. A photograph could be represented and displayed in a digital format by subdividing the image into small equal sized and shaped areas called pixels and representing the brightness of each area with a numeric value or digital number.
