USGS AS-11A analytical stereoplotters are being updated with 
minicomputers, interfaces, and electronics, and additional complete 
plotters are being purchased. A Kern PG2 stereoplotter has been 
modified to provide three-axis digitization of both point and line 
data, and additional digitizing systems for conventional plotters are 
being procured. Other compatible instruments are being acquired--an 
analytical stereocomparator with minicomputer, manual digitizing tables, 
interactive edit system, precision graphic plotters, general-purpose 
computer, and automatic photoprocessors. 
The Defense Mapping Agency digital terrain data tapes (from 
1:250,000-scale maps) are being distributed to civil users through 
NCIC. 
9. Several developments have taken place in the area of 
orthophotography: 
a. A digital off-line orthophoto system has been 
developed. Its components are: (1) a servo-controlled 
profiling device for a stereoplotter (units have been 
built for the Kern PG-2 and a Zeiss C-5 Stereoplanigraph); 
(2) magnetic tape profile recording and playback unit; 
(3) digitally controlled GZ-1 orthoprojector. 
b. Comparative tests have been performed on eight 
commercial orthophoto instruments, and additional 
tests on other instruments have been planned. 
c. A GPM-2 instrument has been installed to prepare 
orthophotos and digital terrain data from high altitude 
quad-centered aerial photographs. 
d. Four experimental projects were performed by com- 
mercial contract to determine the utility of large 
scale (1:1200 to 1:6000) orthophotographic maps for 
urban areas. 
e. Experiments were conducted to classify coastal 
wetlands on 1:10,000 scale orthophotoquads prepared 
from color infrared photographs. 
6. A variety of experimental cartographic projects were con- 
ducted with Landsat Multispectral Scanner (MSS) records. These 
include: 
a. Color infrared versions of state base mosaics at 
scale 1:500,000. 
b. Single band mosaics and image bases for standard line 
maps at scales 1:250,000 to 1:500,000. 
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