GEOG 4354 Lecture 6: September 12 - Digital Data and Imagery
Document Summary
Introduction to remote sensing september 12, 2016. Power of use with other forms of data. Can be very helpful but ever conversion leads to degradation. Ground coverage of a single scan line. A continuous electrical signal is subdivided into equal units, each represented by a single digital value, based upon the average intensity of the signal within the interval. Digital values are known variously as brightness values (bvs), digital numbers (dns), or. Instruments must be calibrated against a known standard to permit scientists to match brightnesses observed on imagery to known values. Calibration of remote sensing instruments is often accomplished by aiming the ifov at a target of known brightness, such as a standardized panel, a uniform surface (e. g. flat desert terrain, clear water bodies) or a calibration standard. Radiances: measurements of absolute brightness recorded in physical units; real numbers; comparable across all scenes, used when it is necessary to.
