ison with à 
d examined 
dge of the 
atrol leader 
hotographer 
present. The 
usually be 
from the 
nd only in 
cases is it 
to make 
ot generally 
) take meas- 
n order to 
he target, 
may some- 
) advantage 
to measure 
sions of. a 
; possible to 
one knows 
ngth of the 
d the dis- 
determined 
aerial photo 
le and gun 
ts should be 
reconnoitre 
nce without 
carried out 
issance, and 
trained and 
changeable, 
leoptic with 
ume sight or 
t-class ones, 
anchromatic 
  
  
  
and infrared photography. For the 
greatest focal length, the aperture 
should not be less than 1:11, and 
should, preferably be as much as 1: 
6.3. A night lens with an aperture of 
1:2 or more, and with a focal length 
of 4-8 in. (approx. 10-20 cm) is, if not 
necessary, at least desirable. The mag- 
azine of the camera must be exchange- 
able, so that the different kinds of 
films may be changed quickly; the 
sets of filters should be well assorted. 
The size of the photos must not be less 
than 21/4 X 31/4 in. (6 X 9 cm). Cam- 
eras of this type are not to be found 
on the open market, but must be spe- 
cially built (see fig. 9). 
In order to take full advantage 
of the resources of the camera, it is 
necessary that the processing be done 
in a photographic laboratory, which 
should naturally be situated near the 
place where the photos were taken. A 
mobile laboratory, suitable for this 
purpose can, for example, be housed 
in a small covered motor vehicle. It 
should be possible to do the develop- 
    
  
Fig. 8. For detailed reconnaissance specially 
constructed cameras are used. A Swedish type 
can be mounted with a periscope for taking 
photos above parapets. 
(Manufactured by Ress AB, Victor Hasselblad, Gothenburg) 
ing, printing, (even dia-positive), and enlarging in this laboratory. 
Instruments for stereoscopic treatment of the photos and projection possi- 
  
Fig. 9. Detailed reconnaissance cameras should have exchangeable 
lenses. 
  
bilities should also 
be on hand. 
Personnel em- 
ployed in detailed 
reconnaissance is 
the most skilled 
photo staff at the 
front. For this 
reason, these peo- 
ple will sometimes 
also beused for other 
photo assignments 
of a qualified na- 
ture, and should, 
therefore, have ac- 
cess not only to 
the specially built 
reconnaissance 
cameras, but even 
to other kinds of