color-reversal photographs. 
Most replies indicated a desire to keep negative densities within known limits, but 
very few reported use of sensitometric control. Photo-electric exposure estimat 
ion is being used more frequently, especially for color, but most operators still 
rely on tables and experience, apparently with satisfaction. 
Printing Techniques 
Automatic dodging printers are now widely used, but replies indicated marked 
differences of opinion both about their value and the desirable spot size. Some 
users felt that the improvement in quality was real and well worth having, others 
that it was doubtful except in special cases (e.g. negatives exposed in Antarctica) 
Some indicated no need for a smaller scanning spot, but on balance there was a 
strong desire for this. 
A new method of contrast control using color filters in printing is reported from the 
German Democratic Republic. 
Stereoscopy 
Little information was supplied on work performed in this area. West Germany 
reports studies on the theory of steroscopic vision and tests to establish an exact 
theory of the stereoscopic field. A special study related to aerial survey is in 
progress in the Netherlands. The lack of interest in this subject is surprising, in 
view of its importance; possible it is felt to be more appropriate to Commission II. 
Image Location 
The principal reports about activity in this area, including efforts to improve test 
and calibration procedures in accordance with the 1960 ISP Standard, came from 
German Democratic Republic. Reference was made to new calibrating equipment, 
proposals for calibration by in-flight exposures, calculation of distortion-compen 
sating plates for use in the focal plane, and studies on the effects of atmospheric 
refraction and earth curvature. 
Interest in reseau cameras in various forms has increased. In England studies 
are in progress on the flatness of film and its contact with the glass reseau plate. 
The new polyester film bases have been used, in some organizations since 1962. 
A note from Japan says that while these bases have much lower uniform shrinkage 
than cellulose tri-acetate, their irregular shrinkage is about the same. A number 
of other investigations on base shrinkage are reported in progress, and interest 
in this subject remains keen. 
A number of presented papers are expected, and their contents will not be anticipated 
here. 
Developments in Apparatus 
While no fundamental advances are recorded, technical improvements have been 
made in survey cameras. Manufacturers now offer lenses of improved color- 
correction, said to require no focal shift for use with color or infra-red materials.