INTRODUCTION 
A common requirement for employing color systems in remote sens 
ing by aerial photography is an understanding of the variables 
that determine the resultant image color on transparencies,, 
These variables include the film characteristics, the relative 
film exposure, the film development, the reflectance properties 
of the object, the spectral quality of the light impinging on 
the object, the sun-to-reflecting object-to-lens angular rela 
tions and the effects of atmospheric absorption and scattering. 
This study describes the color shifts of the imaged red, green 
and white targets that were associated with aerial flight height 
and relative exposure. 
Since this study uses transparencies obtained for another study, 
the design confounds the effect of altitudinal changes and those 
of exposure differences. While the color determinations were 
statistically analyzed, there is no way to definitely ascribe 
the cause of a color shift to flying height alone unless light 
ing conditions and exposure are kept constant when altitude is 
changed. What is more important, however, is to describe the 
color shifts associated with increasing altitude that take place 
under standard exposure procedures specified for aerial film 
(Kodak, 1970). The approach uses the ground level measured 
reflectance of the targets normalized for relative film exposure 
as the bases for changes in the color, visual transmittance and 
dye density of the imaged targets at each flight date and alti 
tude . 
PHOTOGRAPHY 
The aerial photography for this study was flown during the after 
noon of two cloud-free days, one in early June and one in early 
September. Both photo missions used a Zeiss RMK 15/23A camera 
(153.3 mm focal length) mounted in an Aero Commander twin engine 
plane. Flights were conducted in succession at 15,000 (4600M), 
6,000 (1800M), and 1,500 (460M) feet above the study area at 
Chesterfield, Missouri. Elapsed time between the 15,000 feet 
and the 1,500 feet pass was 1^ hours. Two of the targets used 
were 6 meter square red and green colored rugs. The third tar 
get was a flat white roof. 
Kodak Aerochrome infrared film type 2443 of identical batch num 
ber was used for both flights. Exposure was made through a Kodak 
Wratten filter No. 12 and an anti-vignetting filter. Develop 
ment was by Kodak EA-5 process according to manufactured specifi 
cations .