VGHRS Investigation of the Civil War Museum at the
Exchange Hotel
Additional Commentary
>>>
UV radiation is very energetic so far as film is concerned (as is
evidenced by my experiences in London Hospital which I cited).
There, we found that the response of Ilford Pan F film to
"visible" light which normally required a photographic
exposure of about 1 second, had been transformed into one
requiring 1/500th second. Therefore, if the UV source which we
were using required an exposure of 1/500th second with a film of
50ASA then, had the film speed been 800ASA, the correct exposure
would have become 1/16 of 1/500th second or 1/8000th of a second.
Therefore, even an exposure of 1 second would have totally
over-exposed the film, completely irradiating all the silver
emulsion grains. Once this has happened, no amount of additional
exposure will produce any further effect.
This is exactly what appears to have happened in the case of the
AWFUS image. I have opened this in Adobe Photoshop so that I can
make some measurements. Essentially, the image is of three
high-intensity blobs.What I will call the left-hand one (adjacent
to the wavy purple trace) is slightly less intense than is the
next one over towards the right. Using this Program, I can
measure the intensity in the three colour channels (R, G, B) on a
scale of 0 - 255. The brightest/whitest reading that I can get
for the LH blob is âEUR" R = 236, G = 254, B = 254 whilst
for the middle blob, these values a re âEUR" R = 253, G =
255, B = 252. Now, if the readings had been 255 in all three
channels, then the colour would have been white at the maximum
intensity which this particular film can reproduce. True white
will never be achieved in practice because of the colour of the
gelatine emulsion and the film base, together with some light
scatter by the dye stuff grains all taken together with the
limitations of the scanner, my computer monitor, etc., etc.,
etc.. I think that when all these inherent process limitations
are
taken into account, the values obtained do indeed indicate total
over-exposure.
I will elaborate further so as to clear up any misunderstandings.
The energy of short wavelength light is absorbed by the atoms of
the material irradiated. When this happens, electrons in the
target atoms are raised from some inner and less-energetic orbit
to one which is further out and in which they travel at higher
speed. They then spontaneously slow up again and fall back to
their original orbit, rel easing the energy previously absorbed
as a pulse of light (actually called "a quantum of
energy"). This emitted light will always be at a longer
wavelength than that of the original irradiating light because
some of the energy which was absorbed was used up in moving the
electron up to the higher orbit and only a lesser fraction is
available for re-emission.
To illustrate, let us consider the typical situation when protein
molecules are irradiated with light from a mercury arc lamp using
the 365 nm line of the mercury spectrum. The irradiating light is
below the lower limit of sensitivity of the human eye, so the
background appears black. The protein material, however, absorbs
the short UV radiation and then re-emits light of longer
wavelength which is a green/cyan colour with a wavelength of
about 480 - 500 nm. Note the change in wavelength âEUR"365
to (say) 490 nm.
This phenomenon is called "fluorescence" and should not
be confused with "luminescence", as exhibited by algae
and planktonic organisms in the sea. The light emitted by such
organisms is produced chemically, usually as a result of some
mechanical action, such as the passing of a boat, the stroke of
an oar or the body movements of a swimmer. Often, the
colour produced is very similar to that described above for
protein molecules in UV light but the mechanism is very different
UV light is not the only waveband which will produce
fluorescence. The compound fluorocein iso-thiocyanate can be
excited by the short VISIBLE wavelength of 485 nm (deep violet)
and fluoresces a bright apple green colour at 550 nm. The dye
stuff known as Texas Red, can be excited at a wavelength of 550
nm and emits a beautiful red light at 570 - 580 nm.
These are just two of many possible examples The important point,
however, is that in every case, the exciting wavelength is
considerably shorter than is that of the emission.
Now to consider the "optical brighteners" incorporated
into household detergents. Ordinary sunlight contains some small
amount of UV radiation. Fortunately, the amount is very small (or
life would not be possible on this planet) but at sea level it is
sufficient to provoke weak fluorescence of the optical brightener
at a wavelength equivalent to a bluish colour. This makes white
clothes appear more reflective and therefore, whiter.
Now to the so-called "black lights" used in discos. The
filaments of these lamps are "over-run" ... a rather
high current density is applied to them so that they become
hotter than normal and reach a temperature of about 3500 degrees
Kelvin. (The zero point of the Kelvin temperature scale is at
MINUS 273 degrees Celsius. This is the temperature at which all
atomic vibration ceases and it is known as "absolute
zero", for obvious reasons). A tungsten filament heated to
about 3500 deg K begins to emit a small amount of UV radiation
although the bulk of the emission (about 90 - 95%) is in the
visible and Infra Red regions. All of these longer wavelengths
are filtered out by means of a suitable coating on the envelope
of the bulb so that only the UV component is radiated.
The ambient illumination in the disco is usually rather low so a
person's eyes become somewhat dark-adapted, the pupils expanding
and the sensitivity switching automatically to deal with low
light intensities. As previously mentioned, the human eye is not
sensitive to UV radiation, so the visible ambient illumination is
apparently unchanged but ... the small amount of UV radiation
does excite fluorescence of the optical brightener residual in
the clothes of the patrons. Since their eyes are
dark-adapted, this emission appears to be rather bright.
When I wrote my original reply. I had not seen the image
photographed and I assumed that it was a nebulous blue blob. If a
"black light" bulb were shone onto a piece of cloth
which had been washed in detergent, the cloth would fluoresce and
thus rather mysteriously "glow in the dark". This, I
suggested, was one way in which such an image could be faked.
I thank you for your fairly detailed information regarding the
photograph of the blobs but I'm afraid that it doesn't help me
very much. I am afraid that I just cannot see how this could be
of a naturally-occurring event. I am loath to impugn the
integrity of anyone but this image just cannot be reconciled with
what I know of photographic materials, the physics of these and
the scenario as you describe it.
UV radiation is produced by a hot source at a temperature of
3500 deg K or higher ... the higher the temperature, the shorter
the wavelength of the emitted radiation. Now, a source is NEVER
completely homogeneous either with regard to its chemical
composition or the distribution of energy within it, so
wavelengths longer than those of the UV band are always produced.
Most of the energy appears in the Infra Red or as heat, at
wavelengths longer than say 800 nm. The only way that a source
can APPARENTLY emit selectively is if a filter of some sort is
interposed between it and the detector. This is precisely the
situation in the case of the black-light bulbs mentioned above
... they are coated with a filter material and APPARENTLY emit
only in the UV and IR regions, since the visible wavelengths from
say 400 - 800 nm are being absorbed by the
filter coating. You mentioned that the filter placed over the
camera lens had very similar properties. However ... the filament
of such a lamp is glowing white hot and if the envelope of the
lamp were not coated with the filter material, the room would be
brilliantly illuminated by "white" light. Yet ... you
tell me that it remained in almost total darkness.
I'm sorry, but this is just not possible. No "cold"
source can emit solely in the UV region whilst, if it is hot
enough to emit UV, then it MUST emit longer wavelengths also,
some of which will be visible to human eyes. Since the image as
presented contradicts known and well-established physical laws,
we are left with the conclusion that it is probably faked.
You may well argue that it is precisely because this image does
contradict known laws that then it MUST be of some hitherto
unknown phenomenon. I cannot refute that argument for there is
insufficient evidence but I would remind you of the
philosophical/rhetorical principle known as "Occam's
Razor". First expounded by Roger of Occam in the 12th/13th
Century, this states that it is unwise to seek more complex
explanations for phenomena when a simple explanation will fully
suffice. In the cruder jargon of our modern world, it is embodied
in what is known as "The KISS philosophy ... Keep It Simple,
Stupid !"
In my previous letter I postulated that a fake image could be
produced by shining light from a "black" bulb onto some
previously-washed cloth material, which would then "glow in
the dark" as it fluoresced. The image you present seems to
have been produced in a much cruder manner. The image is
completely explainable as being produced by the operator
shining a "black" bulb directly into the lens whilst
the shutter was held upon in a dark room. The wavy trace coming
in from the left is commensurate with the bulb being moved
towards the lens immediately after it was switched on. The burned
out over exposed areas would result from holding the bulb close
to the lens. The strong trace moving towards the upper boundary
would result from moving the lamp slowly upwards. The purple halo
around the image could well result from the small leakage of
longer wavelengths (just inside the visible region) which is a
characteristic of these lamps.
You state that the lens was set to an aperture of f/2 and was
focussed at a distance of six feet. Why was such a limiting set
of conditions chosen ? Presumably, the room was fairly large
(since you state that it was part of some sort of museum and
contained glass display cases) When a lens having a focal length
of 58mm and with the aperture set at f/2, is focussed at six feet
distance, the depth of field is extremely shallow and extends
from 5.79 - 6.22 feet; a range of 0.43 feet ... or just over 5
inches. Why, in a room of considerable size, did the photographer
choose to use such a shallow depth of field, thereby
ensuring that anything not located in this narrow spatial range
would be rendered un-sharp ? It just doesn't make sense.
Perhaps the photographer might possibly advance the argument that
he chose an aperture of f/2 as being the largest available and
thus best suited to the capture of weakly-illuminated objects.
This is indeed true but only partially so for films having speeds
up to 1600ASA are available and by "push processing"
their speed can be increased by two stops (to an effective speed
of 6400ASA), although image sharpness will then be degraded. The
point, however, is that the photographer was
prepared to make very long time exposures (you cite as long as 15
minutes, in one instance). He thereby completely circumvented the
limitation of film sensitivity.
However, even if we allow that the photographer was justified in
using the largest aperture available, he could have maximised the
depth of field (and thus the chances of capturing an image) by
setting his focus to the hyperfocal distance which, at these
settings, is 167 ft. At this distance setting, the depth of field
is at its maximum and extends from half the hyperfocal distance
(say 84 feet) to infinity. If a distance setting of 167 feet was
too large for the room then a distanc e of half
the hyperfocal distance (84 feet) would give a depth of field
extending from 56 to 169 feet .. the narrow field some 5 inches
deep at a six-foot distance setting has expanded to 113 feet.
If even 84 feet was too large then setting the camera focus upon
a distance half way between the camera position and the furthest
extent of the field of view would give the best chance of
capturing an image which was nearly in focus. By choosing a
distance of six feet with the lens aperture set at f/2, the
photographer was reducing the probability of securing a sharp
image of a randomly-positioned event to some vanishingly-small
value. I must say that I am highly suspicious that any
photographer would make such a fundamental mistake in camera
operation unless, of course, his intention was to deliberately
create out-of-focus images which could not be positively
identified.
All the evidence seems to me to indicate that you hav e been the
victim of some sort of hoax. I must observe that I find this sort
of activity (faking phenomena in this way) to be particularly
reprehensible. There are many strange and wonderful things in
this world (and indeed, the universe itself) which deserve
serious investigation. However, such matters are outside the
mainstream of scientific research. The small minority of hoaxers
bring such unconventional investigations into disrepute and
seriously impede them. They also serve to act as a brake to
anyone contemplating such investigations who might well fear for
their scientific reputation and career prospects should their
unconventional interests become common knowledge.
I am sorry to end on this somewhat sour note but the initial
description and the image you subsequently kindly supplied just
cannot be reconciled with my limited knowledge of physics or
photography and so it is not possible for me to reach any other
conc lusion than that of attempted hoax by person or persons
unknown.
With that said, I trust that you have found my analysis to be
sympathetic to your endeavours. Since I am now retired, I have no
reputation to hazard and I would therefore be prepared to place
such expertise and photographic equipment as I possess at the
disposal of any group undertaking serious investigation of
paranormal phenomena.
I would like to close by wishing you and your co-workers good
fortune in your future investigations.
Best regards,
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