- 5 w 
screen of the sighting device with a spead proportionate 
to A , Bo tbat visual control of functioning of the 
automation is possible. 
The intervals between consecutive exposures are de- 
termined by an automatic command with accuracy suffici- 
ent to maintain the prescribed overlap with an error 
* e-25. 
Both the electronic and automatic commands allow to 
reduce by 20% the number of pictures in a strip, espe- 
cially in mountainous and hilly regions. 
In connection with certain aerial surveys, special 
radio-geodetic systems have found application in the 
USSR to reduce the volume of ground operations conducted 
for establishing geodetic control and determining coor- 
dinates of projection centres. | 
For ice reconnaissance, a "TOROS" side-looking 
radio-locating system is used. It permits to obtain 
imagery which by its quality is similar to that photogra- 
phic,and this-at any time and in any weather conditions; 
this makes the radio-location survey indispensable for 
exploring regions of difficult access and (or) covered 
with clouds. 
COMMISSION II 
Theory, methods and equipment for stereoplotting 
To meet the requirements of modern photogrammetry, 
analytical and analog plotting instruments for large- 
-scale mapping and differential photorectifiers have 
been developed in the USSR. 
Instruments for analytical methods of plotting: 
Stereocomparator SKV-I.- The instrument is designed for 
measuring point coordinates on aerial 18 x 18 cm photo- 
graphs. At the operator's will, and :äepending on the 
character of work to be executed, any of three magnifi- 
cations of the observing system ( 8 X, 46 X, 20 X ) may