The "Montana" film contains six independent data (as functions of
time) on about 225 frames (frames 65 to 290), which describe the UFO
images, i.e., the two degrees of freedom of each dot (as depicted on
two-dimensional film after the foreground appears on frame 65) and
the apparent diameter of the developed image of each on all 290
frames (no ellipticity could be seen in the images except for
occasional image smear due to uneven panning). In the analysis it was
convenient to treat the UFO's as a system. The four degrees of
freedom chosen for this system were the azimuth and altitude of the
midpoint on the line of centers between the images, their angular
separation and their inclination to the horizon. The inclination to
the horizon was found to be very small, the objects appearing to move
almost in a plane parallel to the ground. There is a slight decrease
in the angle of inclination as the objects regress, but its small
value is almost masked by random errors inherent in the measurements.
Figure 3a presents a plot of the angular altitude, h, and the
azimuth, A, of the midpoint of the line of centers after frame
65 (i.e., after a measurable foreground appears), and Fig. 3b
presents the separation distance ratio
theta_e/theta as a function of time, where
theta_e is the initial angular separation
(frame 1) and theta is the angular separation at any
given time. In both of these plots some frames were not measured,
e.g., due to obscuration of the images during water-tower passage, or
were missing (there were frames missing between frame numbers 177 to
180 on the 35 mm print that was measured for separation distance, but
these were accounted for in the time scale using the 16 mm original
as a basis). About 225 frames after the foreground (ventilator duct)
appears on the film (i.e., after the 290th frame), the objects can no
longer be clearly identified and measurements become very uncertain.