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Firstly, in order to determine the exposure condition for 
these three films, Kodak step tablet No. 2 was exposed on each 
film. After development, the D-H curves as shown in Fig. 2. 
were measured, Assuming that the highlight part of the color 
negative film are corresponded to the shadow part of the reversal 
film, it was found that the exposure for the reversal color 
film is one half times the color negative film from these 
figures. 
Then, the targets on the ground test field were photo- 
graphed from air. After processing, the aerial films were 
evaluated by MTF and color reproduction. 
2-1 TEST FIELD 
The test field was at the southern part of KAWAGOE CITY 
near TOKYO, where forests, crops, bare-soils, houses, and 
the other targets were distributed in proper proportion. 
In the test field, three kind of the target with the hard 
boadplates were arranged. 
Each target had been painted with a paint which gives a 
matt surface. The first target has the bar targets of the 
square-wave type, Of which spatial frequencies continuously 
vary 5 to 41,5 lines/mm with the ratio of [2 in two directions 
perpendicular to each other, 
The 2nd target has four steps grey scale,which is used to 
measure the radiation transfer characteristics (or tone repro- 
duction) of the system and to calculate the effective exposures 
on the film. 
The 3rd target has the color targets, red, green,blue, 
cyan, magenta and yellow to calculate the color rendering of 
the aerial color film. 
The 2nd and 3rd targets were imaged as a square of 
1 mm x 1 mm on the image, when the photoscale was 1:5000. 
This size was suitable for a micro-densitometer or a micro- 
spectrophotometer measurement. 
In the field, reflectances of all targets and the solar 
irradiance were measured by a spectroradiometer. 
Fig. 3 shows the spectral reflectance curves of the color target, 
and Fig. 4, spectral distributions of solar irradiance. 
2-2 ACQUISITION OF AERIAL PHOTOGRAPHS 
Wild RC-10, with Universal Aviogon was used for the aerial 
photography in january 1977. 
The photographies were taken in similar condition as exposure 
time 1/300 sec, relative aperture 1:8, and at the scales of