293 
Compte-rendu de la séance du 20 juillet 1956 
à 16.30 heures 
Le Président ouvre la séance et donne la parole à M. G. McNeil pour la présen 
tation des communications de MM. E.L. Merritt, Etats-Unis, T. Yonkler, Etats- 
Unis, et K. J. Fairbanks, Etats-Unis, pas présents. 
Résumé de la communication de M. Merritt, intitulée: »System-testing cine- 
theodolites by stars». 
E. L. Merritt: System 
testing cinetheodolites 
by stars. 
(Publ. V M 1; 
voir USA V) 
A new method of system-testing a Mk 5 cinetheodolite was initiated and 
completed at the Naval Proving Ground, Dahlgren, Virginia, during the period 
August—October, 1955. 
The method is based on the photogrammetric reduction of data obtained 
from star exposures made at regular angular intervals, at known chronometer 
times, and at a known geographic position. Mechanical precision of the rotation 
axes and the accuracy of direction angles are determined with these data. 
The vertical errors are determined from exposures made at regular intervals 
in a vertical plane having a fixed azimuth, while horizontal errors are deter 
mined from exposures made at regular intervals in azimuth having a fixed 
vertical angle. 
The results obtained are given at the end of the report. These data, because 
of the errors of timing, are considered correct to plus-or-minus 3 seconds of 
arc. The errors of timing shall be reduced to plus-or-minus 0.2 seconds of arc in 
subsequent tests. 
It is concluded from the results of the test that the Mk 5 is a satisfactory 
ballistic cinetheodolite, except for an apparent camera-tube-bending effect on 
elevation readings, and that the method of testing provides a reliable know 
ledge of the instrument’s static errors. 
Essai stellaire de cine-theodolites 
Une nouvelle méthode d’essais de ciné-théodolites a été perfectionnée au champ d’essai de la 
marine américaine à Dahlgren, en Virginie, pendant août—octobre 1955. 
La méthode est basée sur des données photogrammétriques stellaires obtenues en exposant des 
pellicules à des intervalles angulaires réguliers et chronométrés, d’une position géographique connue. 
La précision mécanique de la rotation des axes d’un appareil ainsi que la précision des angles 
d’inclinaison sont déterminés de cette façon. 
Les erreurs verticales s’obtiennent par des poses faites dans un plan vertical à azimut fixe, 
tandis que les erreurs horizontales s’obtiennent de poses faites en azimut, mais à un angle vertical 
fixe. 
Les résultats obtenus sont donnés. 
Résumé de la communication de M. Yonkler, intitulée: »Photometric camera». T. Yonkler: 
r»UiT\/T4.-^ J e • e £ e Photometric camera. 
ihe PhotoMetric Uamera produces tour images ot an object from tour sepa- (p u bi. VYl; 
rate angles by a single exposure. Each of the four images is correlatable and voir USA V) 
reference points can be cross identified from one image to another for measure 
ment and analysis. 
Perfectly scaled images are projected to life size and are measured within a 
tolerance of 1/16 of an inch in 72 inches. 
Mirrors are used to obtain the several views by one exposure. Each mirror 
is precisely located to maintain focal paths of equal length for each view. 
The PhotoMetric Camera is being used in American and European research 
centers, universities, hospitals, and industries. A significant application of the 
PhotoMetric Camera is in the field of men’s custom tailoring. The photo 
graphic process takes about five minutes. Approximately thirty measurements 
are determined from the photographs to plot the customer's shape and posture.