Documents / Report
This confidential progress report from the U.S. Naval Photographic Interpretation Center in Washington, dated May 1953 and addressed to the Director of Naval Intelligence, analyzes motion picture film of unidentified objects. The footage was taken in Utah on 2 July 1952 and in Montana in 1950. Analysts used frame plots and densitometer readings, and most of the group judged the images to be light sources. They computed velocities and accelerations that ruled out birds, aircraft and balloons, and concluded the objects could not be identified as natural phenomena or commonly known man-made objects.
From the source: Release of 2026-08-07 Incident: 1950, 1952, Montana, Utah. This file contains a memorandum relating to the U.S. Naval Photographic Interpretation Center’s assessment of two films allegedly depicting unidentified airborne objects, captured in Montana and Utah in 1950 and 1952, respectively. The file documents the Center’s analytic process, assumptions that constrained its confidence level, tentative conclusions, and recommendations for future research. The Center assessed, generally, that the objects depicted in the film demonstrated characteristics that were inconsistent with those of natural phenomena or commonly known aerospace technologies. The memorandum documents the Center’s recommendation for a more well-resourced investigation to corroborate its presumptive findings, citing a lack of funding and personnel. The accompanying charts compare the film’s luminosity with the apparent angular size of the phenomena, using contemporary mathematical modeling and photogrammetric analysis techniques.
·code 01/HWW/lbh
J12
n. r- •Serial: IYIAY 4. l 53
GONFIBBN'i'IAL
S:EX::URITY INFORMATION
Subj: Interpretation of Movies of Unidentified Objects;
progress report on
b. Densitometric tests:
Densitometric data vere obtained with a Densichron, Model 2150
manufactured b:r" the Welch Scientific Company. The ~nsichron has a scale
range of 0-3. The procedure was to project each frame at approximately
22 times magnification onto a fi nely-grained-glass screen. The back
ground (sky) was then measured at several places and the density set to
3.0 (variations in backgrouud densities were in the order of 0.02 and
were regarded as uniform) . A set of three readings vere made of each
of seven objects in Part I, and of the single object in Part III of
the Utah Film. Readings vere ma.de of the entire Montana film.
Enclosure ( 8a and 8b) are graphs of the density readings
obtained of the two lower groups of objects in frames 1-129 of the
Utah film. Enclosure (9) is a density graph of the siogle object (94
frames) in Part III. Enclosure (10) is a graph \l'here six successive
Densichron readings were averaged and advanced one reading each deter
minant.
0£ the Montana film, densities were plotted as above and are
enclosures (11) and (12).
The results of the density readings may be questioned in that
these objects varied in size so that at the minimum sizes the densichron
probe was measuring the entire object, and at the maximum size the probe
was measuring only a portion of the objects. Because of this situation
only the largest readings obtained b scanning the objects were used.
It is understood that normal procedure would be to read the entire object.
This was impossible with the equipment on hand.
In addition the film, with which this investigation was conducted,
is a duplicate of a copy . This raises the question as to whether the
central portion of the objects were burnt out during the duplication
processing. Density readings were made to compare the clear areas and
the objects. It was found- that the minimum difference is o.4. This
indicates that relative luminosity may still be obtained with the pro
cedwe used. Concurrent with the density readings, relative sizes of
the objects were noted in order to correlate distance and luminosity.
Enclosure (13) is a plot of the same object wherein the relationship of
distance and luminosity can be detected in Utah film,
3. Answers to Questions. ,.
,Answers keyed to the questions contained in enclosure (7) of
reference (a) are hereb y presented. They supercede those contained in
reference {c) and present the ~1nal analysis.as requested.
eOifil!BBN'f:EJd;
SECURITY INFORMATION 3 Report, from the pursue collection. The PDF is mirrored here; the original link is above. 23 pages are in the text index: search them above, or from the library's search.