* 
a 
FIGURE 4. These four photos were taken simultaneously with a 4-lens spectraband camera system. The photos 
above are: Upper left, Plus-X panchromatic with a Wratten 25A filter (0.6-0.72 micron); upper right, Plus-X 
panchromatic with a Wratten 61 filter (0.46-0.61 micron); lower left, Infrared Aerographic with a Wratten 47B 
filter (0.85-0.50 and 0.72-0.95 micron); and lower right, Infrared Aerographic with a Wratten 89B filter (0.72- 
0.95 micron). Tone differences for range features seen here may be either quite pronounced or quite subtle, de- 
pending upon the narrow spectral bands which are compared. Interpretation of these images can be facilitated 
by additive color enhancement techniques, whereby a single-color composite image is made by superimposing two 
or more black-and-white images, such as those above, with various colored filters. 
(2) Photoelectric scanning of  black-and- 
white images. In this technique, the black- 
and-white images are automatically scanned to 
determine tone signatures for objects in the 
scene. Each signature is characterized by a 
coded symbol. The digitized printout is then 
automatically processed to determine the kind 
and quantity of objects in the original image. 
(38) Automatic tone signature recognition 
using a computer (Laboratory for Agricultural 
Remote Sensing, Purdue University 1967.) 
This process, designed primarily to analyze 
many channels of optical-mechanical scanner 
data, involves recording energy responses on 
magnetic tape. The computer then compares 
the energy response from the magnetic tape 
with known energy responses for previously 
identified agricultural crops. The matching of 
these signatures by the computer permits rapid 
crop identification. 
174 
OUTLOOK AND SUMMARY 
It should be evident from this review that 
remote sensing offers great potential for gath- 
ering information for range and wildlife in- 
ventory and management. However, if its full 
potential is to be realized, range and wildlife 
managers must understand matter-energy rela- 
tionships, sensor limitations and capabilities, 
factors which either limit or enhance image in- 
terpretability, applications, and benefits. Man- 
agers should also be aware that a great gap 
currently exists between the capability for 
gathering a large amount of remote sensing 
data in many portions of the electromagnetic 
spectrum and the limited capability for han- 
dling and analyzing it (Lent and Thorley 
1968). Furthermore, the average user may be- 
come overwhelmed by the expense and sophis- 
tication of certain remote sensing systems. He 
