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A. P. Colvocoresses

Publications and source records attributed to A. P. Colvocoresses.

7 recordsLinked to original sources

Image mapping with the Thematic Mapper.

This paper deals principally with Landsat Thematic Mapper (TM) image maps as published by the US Geological Survey (USGS). Landsat data have certain characteristics that make them suitable for conversion into image maps. These characteristics involve 1) spatial resolution, 2) geometric fidelity, and 3) spectral response. This paper analyzes the three mentioned characteristics and discusses the processes involved in producing TM image maps.-from Author

Photogrammetric Engineering and Remote Sensing

The relationship of acquisition systems to automated stereo correlation.

Today a concerted effort is being made to expedite the mapping process through automated correlation of stereo data. Stereo correlation involves the comparison of radiance (brightness) signals or patterns recorded by sensors. Conventionally, two-dimensional area correlation is utilized but this is a rather slow and cumbersome procedure. Digital correlation can be performed in only one dimension where suitable signal patterns exist, and the one-dimensional mode is much faster. Electro-optical (EO) systems, suitable for space use, also have much greater flexibility than film systems. Thus, an EO space system can be designed which will optimize one-dimensional stereo correlation and lead toward the automation of topographic mapping.-from Author

Photogrammetric Engineering and Remote Sensing

New papers related to remote sensing of the earth

Worldwide experience of many individuals and organizations with remote sensing data acquired from space, primarily Landsat-1, -2, and -3, has demonstrated its utility for land use classification, agricultural assessment, energy and resource exploration, and many other applications. There has been some reluctance to adopt these systems in operational programmes because of a lack of assured continuity of data collection, continuing changes in the systems, and some dissatisfaction with the types of data made available to users. Nevertheless, there is sufficient conviction of the value of satellite remote sensing so that new systems will be developed by several countries in the decade of the 1980's. The status changes continuously as studies are completed, and budgets are adjusted. This review presents the situation at the beginning of 1982.

Open-File Report

Surveying the earth from 20,000 miles

Current space programs aimed at monitoring the earth's resources concentrate on the lower orbital altitudes of 100 to 500 nautical miles. An earth synchronous (geo-stationary) orbit is 19,400 n. mi. above the earth. A powerful telephoto camera at such a location can monitor and record many time-variant phenomena far more effectively than instruments at lower altitudes. The geo-stationary systems characteristics and problem areas related to optics and telemetry are outlined and detailed, and on-going programs are discussed as they relate to the geo-stationary system.

Image Technology