626 PHOTOGRAMMETRIC ENGINEERING 
     
   
   
   
   
   
   
   
  
  
  
  
   
   
    
  
    
   
  
  
  
   
    
from the curve for Super XX corrected to These results emphasize the necessity o 
eye sensitivity with a Wratten 13 filter. calibrating air survey cameras by a pro. 
Image shifts between these two wave- cedure which closely simulates conditigy 
lengths were then read from the curves of of use. The error investigated here arg, 
Figure 2 and plotted to give the compari- primarily from the visual test procedi, RIKE 
son curve in Figure 4. having the wrong chromatic sensitivity 
This procedure is only a rough approxi- It is also highly probable that similar 
mation to the theoretically correct one errors would arise from other departurs 
which would require emulsion character- from normal conditions of use. 
istic curve data for all wave-lengths and 
complicated integration. However, the 
agreement between the two curves is 
sufficient to confirm that the differences 
found between the two salibration proce: Measuring their Resolution, [image Hume 
dures can be attributed chiefly to the nation, and Veiling Glare. 
chromatic differences of distortion of the 2, Carman, P. D., “Control and Interferometri; 
* lens as seen by two spectrally different Measurement of Plate Flatness," J.O.SA 
receivers. 45, 1009-1010, 1955. | 
REFERENCES 
1. International Society of Photogrammetry 
Commission I, Specification of Methods oi 
Calibrating Photogrammetric Cameras ay 
INTO 
Reprinted from 
PHOTOGRAMMETRIC ENGINEERING 
September 
1956 
Printed in France. — CHAIX, Paris. — 2176-TT-6-56.