OPA OT AN PNR PETE 
  
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Question 3: Do you have good control of temperature and pressure and can 
you give range? 
NOTE; While many aircraft are not pressurized, some cameras are sealed with 
rubber gaskets subjecting the lens and filter to external temperatures and 
pressures. A temperature gradient is thereby created (see figure.1). 
Temperature Control (Windows) 17 
No Temperature Control 26 
Camera Heaters 19 
Pressure Céntrol (Windows) 17 
No Pressure Control 53 
Reduced Pressure 8 
Pressure to 30,000 feet, „42°C 
Question 4: Do you have a window? Is it heated? 0% 
No Window 55 
With Window 17 
Window Not Heated 7 
Window Heated 10 
Question 5: 
a. What are the coldest temperatures at Which you do aerial surveying? 
b. How do you protect the camera prior to flight? 
c. What would be the maximum cold temperature during flight. 
a and c are essentially the same question and where there were differences, 
the coldest value was used. Figure 6 shows the distribution of the 67 
values plotted which extend fmom -60'C to + 20°C and peak at 30°C. 
862 lies between -50°C and -5°C and 60% were 300C or lower. @ à 
The answers to preflight protection of the cameras are most interesting. 
They show that many photographers are knowledgeable of temperature problems. 
21 store camera in aircraft 
7 store in air conditioned area 
9 store in carrying case 
17 have no particular protection 
2 gradually bring to outside temperature