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Analysis of a Photograph of a High Speed Ball of Light

Figure 8

UAP Head Area Emphasizing Coronal Micro-Structure
(450 dpi scan, B=10, C=15, emboss filter)

  The left tip of  the tail can be seen here. The areas lying outside of this central, gray region are of more interest, however. Thin, parallel fingers are seen protruding from the rounded front of this image.  It is interesting that most of these fingers diverge from ten to fifteen degrees arc from the UAP's flight path.  What these short protrusions are is not known but may represent energy projections of some sort.

Figure 9

UAP Head Area Emphasizing  Corona Macro-Structure
(450 dpi scan, B=10, C=15, RGB curves filter as described in text)

   These protrusions also appear in Figure 9 where the same part of the image was subjected to a sinusoidal filtering (RGB Curves function) using seven (7) equally spaced cycles across the 255 bits of exposure depth. This yields artificially enhanced profiles of equal luminance. The luminance boundaries nearest the head of the UAP tend to include the projections that characterize the head itself while boundaries more distant do not. This effect seems consistent with a radiation effect that decreases in intensity with distance from the energy source.

   The appearance of separated striations within the white tail behind the UAP appear to be consistent with condensation trails of a blunt-nose body in sub-sonic flight through Earth’s atmosphere (Smith, 2001). Of course, the tail may be produced by a totally different mechanism. In addition, if the UAP was travelling at a supersonic velocity there would be a significantly different appearance of the bow shock wave than is seen in the photograph.  Further, the sailplane pilot did not hear a sonic boom nor feel any sudden air buffeting during or soon after the UAP passed him which would be consistent with a vehicle travelling at sub-sonic velocity.

   The last test performed on the head of the UAP consisted of  “stretching” the exposure so that only thirty [about 12%] of the 255 total  (245 minus 215) bits of input  (exposure) “depth” were stretched over two hundred (200) bits of output “depth.”  This was done to see if very low contrast detail might lie buried within the greatly overexposed region of the UAP’s head.  Figure 10 shows what was found.

Figure 10

IAP Head Area
With Luminance Stretching
(450 dpi scan, B=-5, C=0,  Stretched Exposure)

   The magnification and image centering of Figure 10 are similar to that of Figures 8 and 9 for sake of comparison. The luminance stretching was performed only within the smaller inset square to permit comparison of its diameter with the unstretched image (seen in the remainder of the figure.  It may be noted that the front edge of the head is relatively circular and (again) includes several short protrusions located near the top of the head. The spherical shaped object that Mr. Williams perceived likely corresponded to part of this rounded region.

Sun's Location, Sky Luminance, and Weather Analysis

   On July 16st 1988 at 1400 PST the sun was at 56 deg. 37.8 min. arc elevation and 244 deg. 33.6 min. azimuth at this location. These values are useful in studying illumination and shadows on the UAP, sailplane, and chase plane windows. The reported heading of the sailplane (approx. 45 deg.) at the moment of the photograph is consistent with the location of the sun's shadow on its fuselage. In addition, a rather significant amount of sunlight is also reflected from the earth’s surface upon the underside of the sailplane as seen in Figure 3.

   No clouds are visible in the photograph which supports  Mr. Williams' statement that clouds had not yet developed at this hour of the day.

   The entire frame was scanned at 175 dpi and a brightness filter applied to emphasize the range of luminance along lines A and B (i.e., upper right to lower left). Figure 11 presents the resultant image. When the image is rotated about thirty degrees CW these measurement lines represent the sky's horizontal  luminance gradient. Individual luminance values (3 x 3 pixel cursor) are shown at their measurement location. It may be noted that the sky in the upper right-hand corner of this image is visibly darker than it is in the lower left-hand corner. A luminance difference of about x 2.4 was found along line A which is larger than would be expected from usual atmospheric particle light scattering across this narrow an angle of sky (Allard, 1876).

Figure 11

Sky Luminance Distribution  (175 DPI scan, B=+22; c=+76)

Windshield and Side Window Optical Analysis

   In order to better understand the possible cause of this large luminance gradient several hypotheses were formulated. The first is that sunlight struck the Mooney's right-hand window to create the veiling luminance seen in Figure 11.  An attempt was made to obtain geometric details of the side window’s rate of curvature and other geometry.  A rough estimate of these parameters was made based upon inspection of a front-view photograph of this aircraft (cf. Figure 12). The passenger's side window possesses a large radius (approx. 24) horizontal curve over its upper half progressing to a nearly flat plane over its bottom half.

Figure 12

Nose View Photograph of Mooney M20S

   Assuming that the chase plane was beginning a left-hand bank away from the sailplane when the photograph was taken the camera's line of sight would probably have been through the lower, planar part of the window.  With the Mooney's heading of approximately 360 deg. and sunlight azimuth at about 244 deg, sunlight could not have struck the tinted plexiglass side window.  In short, the lighting conditions were perfect for this photograph with the sun illuminating the top and left-hand side of both the Mooney and the sailplane; the window and camera both were in shadow. The gradient of the sky's luminance seen in Figure 11 is not likely caused by sunlight falling on the Mooney's side window if the aircraft headings are those assumed here.

   A second working hypothesis is that this large luminance gradient across the film plane may have resulted during its processing if a typical darkroom environment has been used.  The Kodak film specifications state: "Do not use a safelight. Handle unprocessed film in total darkness." (Kodak, pg. 2, 1997) Fortunately, Mr. Williams was able to locate five other frames taken from the chase plane during the same flight.  He indicated that the photograph shown in Figure 13 is very likely the frame obtained just prior to the UAP photograph (Fig. 3; cf. footnote 7. This frame allowed a comparison to be made of the sky's luminance gradient with that of the UAP frame; approximately the same range of luminance was found in each which argues against the second hypothesis as well as a third.

   The third hypothesis is that the UAP had somehow caused additional exposure of the film perhaps due to emitted radiation of some sort.  Figure 13, taken many minutes before the appearance of the UAP, suggests that this possibility is very unlikely because of a similar amount of luminance gradient present here as well.

Figure 13

Photograph of Sailplane Taken Several Minutes Before the UAP Photo

   The fourth hypothesis is that this luminance gradient is merely that of the natural daylight sky under these conditions.  Inspection of all photos provided by Mr. Williams tends to support this hypothesis even though the range is higher than would be expected (Allard, 1876, Koschmieder, 1924).

Calculations of Possible UAP Velocity

   If the UAP (1) travelled in a straight line, (2) travelled at a constant velocity, (3) was seen for five or ten seconds (t) total, (4) travelled through the horizontal angles (Col. A - see below), and (5) was either one or two miles away from Mr. Williams (Col. D) it would have had to travel at the velocities (Col. V) shown in Table 2.

Table 2

Calculated UAP Parameters
for These Assumed Parameters

 Total Horizontal  Angular rate     Duration     Distance (st.mi.)   Total Distance    Velocity

 Angle (deg arc.)      of UAP           (sec.)         from Sailplane     Traveled (st. mi.)   (mph)
  UAP Travelled     (deg./sec.)            t                      D                                                     V
      in Time "t"
            100                  20                    5                      1                      2.38                 1,714
            100                  20                    5                      2                      4.77                 3,434
            100                  10                    10                    1                      2.38                    857
            100                  10                    10                    2                      4.77                 1,717
            100                  10                    10                    3                      7.15                 2,574
            110                  22                    5                      1                      2.86                 2,059
            110                  22                    5                      2                      5.71                 4,111
            110                  11                    10                    1                      2.86                 1,030
            110                  11                    10                    2                      5.71                 2,056
            110                  11                    10                    3                      8.57                 3,085

   It appears that all of these velocities are too large in view of the likelihood that the UAP was travelling at sub-sonic speed for reasons given above.  Either the sighting duration estimate was too short, the distance to the UAP was too large, the angle through which the UAP appeared to pass was in error, or some combination of these factors. Even the 857 mph (bold faced) value given above is supersonic. Clearly, a rather large error exists in these estimated parameters.  Such perceptual errors are not at all uncommon when there are few if any stable, visual landmarks and/or time references available within the visual field (Haines, 1980). Even if the distance to the UAP was reduced to only one-half mile it would have had to travel at 428 mph over ten seconds and 100 deg arc; at 0.75 mile distance it would have had to travel at 644 mph over ten seconds and 100 deg arc given the other estimates.

   The change in azimuth angle through which the sailplane traveled at 110 kts in a coordinated 20 deg banked turn (no side slip assumed) to the right over five seconds equals about 14 degrees and 27 degrees over ten seconds.8  The sailplane would have traversed about 700 and 1,400 feet during these two durations, respectively. Since the UAP was seen initially on the left-hand side of the sailplane, i.e., on the outside of his right-hand turn, Williams would be turning in a direction to keep it in sight slightly longer than if he were in straight flight by about 2.7 seconds.

   A UAP subtending a visual angle of  2 deg. 35 min arc at one and two miles distance  would measure 238 and 475 feet across, respectively. At 0.25 mile distance it would measure 59.4 feet across.

Evaluation of Reporter Credibility

   Mr. John Williams was confirmed to be a licensed pilot (S.E.L. and "Diamond" level soaring pilot with 18 years flying experience) at the time of the event.  He did not possess any waivers or limitations. He claimed to have had 400 logged hours with 350 hrs. in high performance sailplanes "…in multiple flight envelopes and conditions."  His reported directorship on a prominent California aerospace museum in the 1980s also was confirmed.  His clear and detailed knowledge of aeronautics and flight details was found to be accurate in every respect. No evidence of any kind could be found that he ever attempted to capitalize on this photograph in any way.


   Two primary subjects will be discussed:  (1) the differences (and possible causes) between what was reportedly seen and what was recorded on the photograph and, (2) the ambiguity of whether or not the negative submitted was original or a copy negative and reasons for accepting it for study.

   (1) Differences Between What was Seen and Photographed.  Mr. Williams remarked that the UAP looked to him like a “large reflective sphere … almost like a large ball bearing."
But this is not what his photo looked like. A quite similar situation exists with the 1956 report by Childerhose discussed earlier. And, when asked to comment on whether or not he remembered seeing a parallel upper edge to the vapor trail that is visible in his photograph he remarked, "The UAP looked more distinct and spherical than it does in the photo, with an area to the rear, several times its diameter that had a vapor quality."  This perceptually-based description clearly implies the presence of an object with a polished metal surface and not a diffuse white ball with a vapor trail that is seen on the film. He did recall seeing a "tail" behind it.

   Several possible explanations exist for these appearance differences: (a) Williams' memory may have been modified somewhat over the intervening years.  Such examples of memory modification are well documented (e.g., Shepard, 1979).  (b) Williams changed the visual description of the UAP for some unknown reason.  The likelihood of this seems small in view of the fact that his description of the UAP didn't correspond at all to the photograph he submitted. This argues in support of his honesty and self-assurance in this sighting detail.  (c) The radiation reflected or emitted by the "spherical" UAP affected this film differently than it affected his retina and visual system. This last possibility deserves further comment related to both the geometric and the spectral sensitivity aspects of the case.

   Geometric Aspects.  The author has conducted laboratory research on both the perceptual and photographic effects of using ultra-high luminance targets in support of the space program (Haines, 1965, 1966, 1968, 1969, 1971) and has photographed highly polished metal spheres and other surface shapes under full sunlight conditions (e.g., Haines, Fig. 39, 40; 1980). These studies clearly demonstrate that the normal human eye perceives very bright targets differently than they will appear on film that has been exposed under so-called "normal" conditions.  Let us first consider the visual appearance of a polished metal sphere. For prolonged, light adapted viewing of a sunlit sphere one will see its entire outline and "metallic" surface (reflecting sky and other background) with a smaller diameter, reflected, virtual image of the sun that is extremely bright.  But the entire surface of the sphere will not appear homogeneously bright. Recall that Mr. Williams' perceptually based statement was that the UAP looked like "a large reflective sphere… a large ball bearing."

   Now consider the visual appearance of a correctly exposed photograph of the same mirror surface target as above. Given the proper shutter speed and aperture much the same object detail will be seen as described above. On the other hand, if the shutter speed and/or aperture are not adequate to reduce the ultra high optical power coming from the spherical target what is produced is a much larger diffuse white area perhaps the same angular size of the entire sphere itself as is seen in the present photograph. Yet in the present photograph the sailplane was properly exposed so the shutter speed and aperture had to be approximately correct for these nominal conditions.  The over-exposed UAP had to result only from its excessive output of optical power. It is likely that this is what occurred in the present case as well as in the earlier Childerhose case.

   Now consider a sunlit sphere in the sky whose surface is not mirror but diffusely reflecting, like white chalk.  It will appear both to the naked eye and on a photograph as an almost flat surfaced object, i.e., its third dimension will be significantly reduced. Its round edge will correspond with its angular diameter.  Each point on its surface will radiate light toward the eye and camera. The difference between sunlit a mirror surface and a diffuse surface sphere is immediately discernable and will not be confused.

   Another possibility in one or both aerial sightings is that the film may have undergone some poorly understood type of direct irradiation effect,9  perhaps due to non-visible (near infra-red?) wavelengths from the source. Further research is called for to find out if this is possible.

   Spectral Sensitivity Aspects.  Another issue is the degree to which Kodak ASA100 color film faithfully captures the same target wavelengths as does the normal human visual system.  In fact, there has been shown to be a relatively good correspondence in this regard (cf. Kodak, 1997). Indeed, if this were not the case such film would not be sold as consistently as it is.  People would not continue to purchase film that did not capture the same hues and contrasts as exist the perceived scene. At the shorter wavelength end of the spectrum  of Kodak 5026 the yellow-forming layer's spectral sensitivity curve extends down to 400 nm while the normal visual sensitivity falls off to virtually nothing at 395 nm. (Prince, 1962).  Much the same correspondence is found at the longer wavelength end of the spectrum as well where the (cyan -forming layer) of the emulsion is sensitive out to 690 nm which is just under the 730 nm cut-off of the normal eye. Thus, the eye can see slightly farther into the near infrared than can this particular film stock.

   What is the possibility that this UAP emitted non-visible radiation that affected the film?

There is no known published research on this important matter. Further research should be conducted to evaluate such a possibility, particularly microwave wavelengths in the 1mm to 1cm wavelength range.

   (2) The Issue of Negative Originality.  Of course it is important to study the original negative of an alleged UAP or other claimed anomaly whenever possible (Louange, 1999) unless it has been lost and a high quality copy, unaltered negative has been made.  As mentioned earlier, it appears that the negative that the author received was not original but a copy.  In addition, of the three frame negative strip received, the UAP was imaged on frame 3A with no exposures on frame 4A or 5A. When Williams was asked about this discrepancy (on March 9, 2001) he said he thought it was original "as far as I know." Whether or not this fact seriously impacts the value of the entire case rests on the personal motives and credibility of the primary witness.  The only other two people who handled the film were the photographer and the technician at the one-hour film developing shop on Convoy Street in San Diego. Since the photographer did not remove the film from the witness's camera but simply handed it all to Williams upon landing it removes him from suspicion.  It isn't known whether the copy negative was made by the technician. He had it for a full week according to Williams who further recalls that he did receive a full roll of negatives back but can't be sure if they were his originals.

   Consider the following: (1) Mr. Williams did nothing with the negative for 11.5 years as far as can be determined other than having two enlargements made - one of which he submitted to the author for study and the other for his office wall, (2) It is possible that the photographer had loaded a second roll of film and then stopped taking photos immediately after the UAP passed by. Williams though that they all headed back to land very soon after the sighting. (3) When the author visited him in his home-office located NW of Seattle, Washington it was noticed that (a) he was a former Naval officer, (b) There was no indication that he had any kind of an interest in ufo or anything occult, (c) At no time did he become defensive or belligerent about the apparent  discrepancy surrounding the copy negative; he merely shrugged it off as something of no great importance. At no time did he contradict himself or give facts that were later found to be in error, and (d) He is well educated, a respected member of the community, and now a salesman of high technology, non-destructive testing hardware and is very precise in his vocabulary and knowledge of flying.  All of these facts tend to support the contention that Williams is a trustworthy individual despite the fact that the negative analyzed probably was not original.  Of course, theoretically, overall case reliability is lessened because of this fact.

   (3)  Other Issues.  A check was made to determine whether other UAP reports had been made at this time, date, and location. No reports to the National UFO Reporting Center (Seattle, Washington) were found other than Mr. Williams' own abbreviated report submitted  on January 10, 2000.  It may be important to note that Mr. Williams did not include the day of the month of the incident in his report to NUFORC.  He had to locate this date in his flight log book for them later.  There also were no sighting reports found in the national data base maintained by Hatch (2001).  A check was also made with an international astronomical clearing house in Czechoslovakia regarding meteorite and bolide sightings; none were reported by astronomers for this time and location.

Preliminary Conclusions

   A number of tentative conclusions are offered as a result of this investigation:  (1) There is no firm evidence of a double exposure or other deliberate hoax despite the fact that the pilot probably did not submit the original negative. (2) Whatever the UAP was it was most likely in sub-sonic flight, as suggested by visual characteristics of turbulence within the tail behind the UAP's head, the lack of a visible bow-wave effect, and the fact that no sonic boom was heard. (3) If the UAP was moving at sub-sonic speed then either the estimated sighting duration was too short, the distance to the UAP too great, the angle that the UAP appeared to travel through was in error, or some combination of them all. It isn't possible to determine which of these estimate(s) are in error. (4) The UAP's visual appearance did not match the appearance of the photograph, a finding that parallels an earlier aerial photographic case.  This difference may be because the total optical power of the UAP was so great as to completely saturate the relatively "slow" film. Indeed, even with extreme computer "stretching" of the highly exposed area it wasn’t possible to locate any significant detail within the central core of the 'white' head. (5) The diminution of the albedo of the UAP’s tail with increased distance behind its leading edge is not consistent with sunlight reflected off of water vapor at these angles. It is as if the particles possessed directional reflectivity or some other non-mundane characteristic.  (6) Very fine micro-structure details were discovered that extended outward from the "head" of the UAP. The nature of the UAP has not been identified as of this date.


Allard, E.,  Memoire sur l'Intensite' et la Portee des Phares. Dunod, Paris, 1876.

Childerhose, R. J., Montreal Star, November 13, 1966.

Gillmor, D. S., (Ed.), Scientific Study of Unidentified Flying Objects. Bantam Books, New York, 1968.

Haines, R. F., The effects of high luminance sources upon the visibility of point sources. Adv.
in the Astronautical Sciences, vol. 20, Pp. 887-896, 1965.

Haines, R. F., and S. H. Bartley, A study of certain visual effects occasioned by factors of so-called glare.  J. of Psychology, vol. 62, Pp. 255-266, 1966.

Haines, R. F., and W. H. Allen, Irradiation and manual navigation. Navigation, vol. 15, no. 4, Pp. 355-365, 1968.

Haines, R. F.,  Changes in perceived size of high luminance targets. Aerospace Medicine,  vol. 40, Pp. 754-758, 1969.

Haines, R. F., The retinal threshold gradient in the presence of a high luminance target and in total darkness.  Perception and Psychophysics, vol. 9, no. 2B, Pp. 197-202, 1971.

Haines, R. F., Observing UFOs.  Nelson-Hall, Chicago, 1980.

Hatch, L.,  "U",  http://www.larryhatch.net, 2001.

Klass, P. J., UFOs Identified. Random House, New York, 1968.

Koschmieder, H.,  Theorie der Horizontalen Sichtweite.  Beitraege zur Physik der Atmos - phare, vol. 12, Pp. 33-53, 171-181, 1924.

Kodak,  Professional Video Analyzing Computer PVAC XL CCD Series 6 with Modification 2. Report CCPR10e, Technical Information Data Sheet, Rev. 11-97  http://www.Kodak.com/global/en/professional/support/techPubs/e26.shtml

Louange, F.,  Procedures for analysis of photographic evidence, Chpt. 21 In Sturrock, P. A., The UFO Enigma. Warner Books, Inc., New York, 1999.

Maccabee, B., Optical power output of an unidentified high altitude light source. J. Sci. Exploration, vol. 13, no. 2, Pp. 199-211, 1999.

McCampbell, J. M., Ufology: New insights from science and common sense. Jaymac Co., Belmont, Calif., 1973.

Prince, J. H., Spectral absorption of the retina and choroid. The Ohio State University Institute for Research in Vision, Columbus, Ohio, Publ. No. 14, March 1962. (Also cf. Haines, 1980, Pg. 119)

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            In  Haines, R.F., (Ed.), UFO Phenomena and the Behavioral Scientist.  The Scarecrow
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Smith, B. E.,  Ames Research Center-NASA, Personal communication, April 4, 2001.



1  Since this case did not involve aviation safety the author investigated it independently from his duties as
      Chief Scientist for NARCAP. Nevertheless, it is included as a NARCAP Topical Report for the benefit
      of those who may be interested in it. 

2   The Mini-Nimbus/C sail plane has a gross weight of 480 pounds and a glide ratio of about 44:1.

3   Ryan airport, Hemet, California, is 1,512 feet MSL with a runway length of 4,300 feet and right-hand
      pattern.  It is used extensively by soaring pilots and hosted almost a hundred such aircraft at the time.  

4 The Mooney 201 was FAA certified in September 1976 and is all  metal construction. It holds four
      passengers and boasts a 200 hp,  flat four cylinder engine. Its high maneuverability and (low wing) visibility
      makes it an ideal candidate as a photographic chase plane. During this flight its flaps were fully extended in
     order to slow to the same speed as the sail plane (approx. 120 kts.).    

5 Mr. Williams claims to possess these other frames although he could not find all of them as of September 1, 2001. 
     He landed at between 1445 and 1500 hrs.

6  It isn't known if the tow plane pilot saw the UAP.  No effort was made to find out at the time.

7  Is it likely that a copy negative was made at this point?  If so, for what purpose? The author received the additional five frames from this roll on August 12, 2001. Since Williams did not take the photos he wasn't sure of their order on the film.

8   The radius of turn for these conditions = 2,944 feet given by R = v2/(tan theta x g)  where: R = turn radius,
       theta = bank angle (deg.), and g = 32.2 deg/sec2.  Mr. Williams estimated (later, March 9, 2001) his bank
       angle to be from ten to fifteen degrees.

9   Irradiation refers to a lateral spread of light exposure on the film beyond the edge of the brighter target.

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