le the first 
ir site by 
Sepi Creek 
work was 
mapping 
Barbara, 
estate de- 
California. 
tion maps 
carmel for 
Highways, 
aphic map 
s County, 
Service. 
the early 
y and took 
it develop- 
otter (Pat. 
1,735,109), 
The Solar 
4 couple 
. 
inimetering 
GINEERING, 
RAMMETRIC 
6. 
"^ PHorOo- 
+111, No. i, 
tereoscopic 
RAMMETRIC 
HOTOGRAM- 
No. 4, p. 30 
y, PHoro- 
d. XIII, p. 
1 Surveys, 
GINEERING, 
HOTOGRAM- 
[0. 4, p. 26. 
ition, The 
Lens Aerial 
verial Cam- 
Colombia,” 
> Vol. III, 
a in Photo- 
RIC ENGI- 
hutters for 
RAMMETRIC 
p. 1. 
Phillips, M. A., “Episodes in Tropical Map- 
ping," PHOTOGRAMMETRIC ENGINEERING, Vol. 
VI, p. 166. 
Podeyn, G. j., Jr. 
“The Fairchild Cartographic Camera,” PHo- 
TOGRAMMETRIC ENGINEERING, Vol. XII, 
p. 345. He 
“Radar Charting, A New Application of Pho- 
togrammetry,” PHOTOGRAMMETRIC ENGI- 
NEERING, Vol. XIV, p. 114 
Sanders, Revere G. 
"Aerial: Cameras and Photogrammetric 
Equipment: A Quarter Century of Prog- 
ress,” PHOTOGRAMMETRIC ENGINEERING, 
Vol. X, p. 136. 
“Design and Construction of Aerial Cam- 
eras," MANUAL OF PHOTOGRAMMETRY, Pit- 
man Publishing Corporation, N. Y., Chi- 
cago, 1944, p. 76. 
“Elementary Elevation Determination from 
Aerial Photographs,” PHOTOGRAMMETRIC 
ENGINEERING, Vol. IX, p. 22; MANUAL OF 
PHOTOGRAMMETRY, Pitman Publishing Cor- 
poration, N. Y., Chicago, 1944, p. 450. 
“Military Cameras for High Speed Air- 
planes,” PHOTOGRAMMETRIC ENGINEER- 
ING, Vol. VII, p. 60. 
“Orient Your Stereoscope Correctly,” PHo- 
TOGRAMMETRIC ENGINEERING, Vol. VIII, 
p. 240, 
"Stereoscopy, Its History and Uses,” PHOTO- 
GRAMMETRIC ENGINEERING, Vol. XI, p. 
101. 
DESCRIPTION OF PHOTOGRAMMETRIC IN- 
STRUMENTS BUILT BY FAIRCHILD 
Stereocomparagraph 
This simple stereoscopic plotting instru- 
ment (see Corps of Engineers history, 
Fig. 3) is used for quickly measuring eleva- 
tions and for compiling vertical data such 
as form lines, approximate profiles, slopes, 
etc. as well as planimetric details directly 
from overlapping vertical aerial photo- 
graphs. Although not as precise as more 
expensive and complex stereoscopic plot- 
ting instruments, the Stereocomparagraph 
does provide a reasonable degree of ac- 
curacy depending upon the skill and ex- 
perience of the individual operator. Under 
ideal conditions when errors due to tip 
or tilt are negligible most operators find no 
difficulty. in plotting to an accuracy of 
1/350 of the flight altitude. Designed for 
attachment to any standard drafting arm, 
the Stereocomparagraph consists of a 
special mirror stereoscope, two adjustable 
PHOTOGRAMMETRIC ENGINEERING 
41 
“floating mark’ assemblies and a precision 
micrometer. The micrometer and floating 
marks are. employed. to measure the paral- 
lax displacements. of various points on 
overlapping aerial photographs. 
Rectoplanograph 
A simple instrument, the Rectoplano- 
graph gives the map-maker a time-saving 
method for rectifying and transferring 
planimetric detail from aerial photographs 
to maps and charts. The Rectoplanograph 
is based on the principle of the camera 
lucida, with which the eye receives two 
superimposed images, one from a photo- 
graph and the other from a map. The 
Rectoplanograph goes beyond this, how- 
ever, with its double prism optical system 
and with its controls which allow plotting 
from any aerial photograph of 9 inches or 
smaller. Photos taken with lenses from 4 
to 12 inches in focal length can be used. 
Magnifying Mirror Stereoscope Type F-71 
Intended for field or laboratory use, the 
F-71 Stereoscope is a high-quality, sturdily 
constructed unit. Its optical system is 
specifically designed and accurately ad- 
justed to reduce eye fatigue toa minimum. 
A detachable four-power binocular is avail- 
able for detailed examination of small 
areas. 
Parallax Bar Type F-163 
In use with the Stereoscope this instru- 
ment makes it possible to measure differ- 
ences in elevation on the spatial model 
created when aerial photographs are 
viewed stereoscopically. The unit consists * 
of a metal bar supporting a micrometer, 
two adjustable floating mark assemblies 
and a drawing attachment. 
Rectangular Coordinate Plotter 
Consisting of a % inch thick glass 
plotting area mounted on. a rigid metal 
table this plotter employs an unique vernier 
coordinate control system. The Plotter is 
used for accurately plotting mapping data 
on rectangular coordinates based on deci- 
mal inch measurements or metric scales. 
It can also be used for drawing grid lines 
very accurately. Operating rapidly it has 
an accuracy of .001 of an inch