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The solution:
After some thought, I realized that the hot spot, as seen through
the viewfinder, comprised a very small part of the bottle's
surface. The rest of the bottle admitted light that illuminated
the subject very well, but this also created some secondary
reflections from the back side of the bottle.
I found that a small disk inserted between the light and the
offending hot spot (as seen through the viewfinder) completely
eclipsed the hot spot (see drawing at left); professionals call
such a disk a "gobo," an abbreviation for
"go-between." A similar gobo could also be used to
remove the reflection from the back of the bottle or glass case,
or I could move the light slightly to bring the subject into a
position to block this reflection This tactic turned out to be
very useful.
 Another effect of using the gobo was to introduce a shadow,
usually slightly outside a region of major interest; there was
also an area of substantial illumination surrounding the shadow.
However, if I aimed the light directly at an interesting area and
the light was not too close to the camera, then this shadow would
not be centered on either the main or central area of interest.
To reduce the shadows, I next added another light with its own
gobo and moved the light to cut out any secondary reflection, as
previously noted. (The more convoluted the bottle, the more gobos
needed.) I mounted this second light not too far from the first.
The idea was to have the shadow of one gobo in the light of a
neighbor.
Three lights best
While two lights didn't provide quite enough light to erase either
shadow, using three lights in a triangular formation worked quite
well - each shadow was then in the light of two of its neighbors.
Aiming all three lights at the same part of the bottle insured
that the shadows were not too far apart and, hence, were in a
fairly bright region of the neighboring lights.
I tried four lights and got a very slight improvement - or was
it my imagination? My spotmeter indicated a variation of
illumination across the region in both the "three light"
and "four light" instances, proving that if you aim for
perfection, you ain't ever gonna get it! At this rate I was about
to start manufacturing gobos.
Generally it was easier to mount the gobos remote from the
lights. I placed the lights to the camera's left and stationed a
rack for the gobos at the camera's right, making sure that the
platform on which the gobos were mounted was substantially above
the subject. This kept the "rabbit ear" gobo supports
out of view of the camera.
To verify that the gobos were placed correctly, I removed the
subject and replaced it with a sheet of white paper. The No. 1
light and its gobo cast a very fuzzy shadow. When I marked this
shadow on the paper, turned the light off, and repeated the
procedure for lights Nos. 2 and 3, the three shadow marks on the
paper showed a somewhat distorted triangle (since I had to move
the lights during adjustment). However, when I turned on all three
lights, the three shadows disappeared!
Specifics on equipment Rabbit ear TV antennas: Buy them
locally, or from American Science and Surplus, 5316 N. Milwaukee
Ave., Chicago, IL 60630; 773-763-0313. These antenna are
extendible with a mounting hole at the bottom that can be used as
a swivel (see drawing above). I didn't paint the shiny shafts of
the rabbit ear because the paint scrapes off. Use strips of black
cloth to avoid reflections.
Six modified swing-arm lamps fitted with 150-watt spotlights:
These are available from most discount stores. (A spotlight
concentrates its light more than a flood, and it illuminates the
field well.) I also bought four "clamp on" lights and
removed the reflectors. When the mounting bench became crowded,
the little clamp-ons could be tucked into a restricted region.
To adapt the lamps, I removed most of the screws from the
swing-arm lights' joints and replaced each with a 6-32xl-inch-long
thumbscrew fitted with a wing nut, a plain washer, and a
lock washer; the plain washer went between the wing nut and the
lock washer. Each swing-arm lamp took three sets of these. (The
extra weight of the spotlights tended to bring down the swing-arm
lamps at the wrong moments, proving Murphy's Law.)
A bench to hold everything:
 Although I had built a fairly large
bench to support all this, I quickly ran out of space and had to
use additional wooden boxes. The bench was 20 inches high, 42 inches
long, and 12 inches wide; I added a stepladder to the right of the
camera (see drawing below).
To provide the necessary shadow I've developed a handy tool - a
gobo disk glued to a 24-inch dowel - which I've named a gobo
probe. It can be easily moved around when trying to establish the
location of one of the mounted gobos or to track down a secondary reflection, which tends to be very
elusive.
I put my camera on a good tripod and focused on the subject,
which was mounted about 10 inches above the Ping-Pong table I used
for a stage. I used a low light to illuminate the lower region of
the ship's hull.
At last, let's shoot the picture!
Here's the method I used to take the photo on the opening page:
Placing the cluster of three lights (to the camera's left) high to
illuminate the deck area, sails, and regions between the masts, I
aimed the first spotlight at the primary area of interest or at
the central region, and saw the first hot spot in the viewfinder.
I noted where this spot appeared on the subject, then got in front
of the camera and moved my head around until I saw the spot appear
at the same point on the subject. Then I moved the gobo until this
spot was eclipsed, checking it through the viewfinder.
Next I moved the light until the secondary reflections
disappeared behind the subject; if the secondary reflections
didn't leave, I knew I needed an extra gobo. Once again I moved
the gobo until the hot spot disappeared, and I checked this
adjustment through the viewfinder. I found that, if possible, it
was much easier to first remove the secondary reflections.
Getting a halo of light around an otherwise eclipsed spot meant
that my gobo was either too small or it was the wrong distance
from the light. For this setup, the best location for a gobo
seemed to be about halfway between the light and the subject. When
I had a large bottle, the hot spot would be larger than for a
small one. For my bottles, the best gobo diameter was about 2 1/2 inches. (I like a gobo that just barely eclipses a hot spot;
although it is difficult to adjust, it cuts out the least light.)
I placed a piece of a concrete block on each gobo assembly - this
held it down, yet left it free to rotate.
After I had made the necessary adjustments for light No. 1, I
turned it off, turned on No. 2, and repeated this "gobo
dance." Lastly, I did the same with light No. 3. These lights
should be about 12 inches apart, and I tried to keep an
equilateral triangular formation; but after adjusting for the
secondary reflections (and, of course, making sure the subject was
well illuminated), the resulting triangle was seriously distorted.
(Note: Not all secondary reflections are objectionable. Some
minor reflections give the project an air of reality. In fact,
with all such reflections wiped out, the model has an artificial
air about it.)
 The support under the neck of the bottle cast a strong shadow
on the base. I aimed another spotlight at this shadow from about
18 inches away, which removed it but created two sets of
reflections, using up two more gobos. I also wanted to illuminate
the lower part of the hull, so I mounted another spot just above
the tabletop and aimed it at a point on the hull just beneath the
foremast, mounting a gobo to clear the hot spot. This produced
lots of secondary reflections because of the light's proximity to
the bottle. Also, since the light from the stem of the reflector's
spotlight wasn't well silvered, this created reflections of its
own. I constructed a visor and slit to block them (see drawing
below). The lip on the top front edge intercepted reflections from
the underside of the visor.
The gate in front of the low-light assembly should be left
loose. I simply leaned it against the front support legs, usually
putting some small blocks underneath for adjustment. I had to vary
the slit width by this means, which is necessary for each setup.
 With all the junk surrounding the photo scene it looked like a
Rube Goldberg setup, from which no good could come! I felt it best
to drape some flat black cloth over much of it. During some of the
tests I forgot to use the drapes. I found this had little effect
except for some spots from the rabbit ears, so I shrouded the
offending ears.
My camera was a faithful Minolta XG-M, placed about 6 feet from
the subject and about 6 feet 5 inches above the floor. The lens
was a highly rated (by PoP's test lab) 100mm f/3.5 Vivitar macro.
I bought 200-speed, daylight-balanced, 12-exposure rolls of print
film so I could finish test rolls quickly and have them processed.
Since I was using incandescent lighting, I made all exposures
through a Hoya 80B correction filter. It took a lot of trial and
error (mostly error) and I used quite a few of the 12-exposure
rolls.
With my lens set at f/3.5 and all lights on, the meter in the
camera called for a 1/4-sec exposure. But I needed all the depth
of field I could get, so I set the aperture at f/22 and doubled
the exposure time at each stop. This brought me to 8 seconds. With
a tripod and cable release this was no problem. I also used
substantial bracketing; 6, 7, 8, 9, and 10 seconds.
When I used this gobo setup for an airplane-in-the-bottle shot,
the lights were mounted more to the right or left since the wings
shaded some of the overhead light; at least one head was needed to
illuminate the wings. The upper wing cast a shadow on much of the
plane if all or most lights were mounted high. In this case it was
better to mount some lights to the side. Every project has its own
special problems.
In general, I found it important to keep the lights - and hence
the gobos-away from the axis of the camera lens. This allowed me
to move the gobos closer to the subject without getting them into
the field of view, and such gobos cast smaller shadows. The
secondary reflections off the back of a bottle of poor quality
presented similar problems.
Inside surfaces create difficulties Light is always reflected
from both the outside and inside surfaces of bottles. This
distorts your hot spot. For handblown bottles and Corning's lab
glass this effect is barely noticeable, but for other glass the
reflected light can have very distorted shapes. This kind of glass
is blown into a mold, which results in the outside having a fairly
regular shape, but the inside has a very irregular surface. In
spite of this, many such bottles are still used for models.
To correct the latter effect I made small cardboard patches to
clamp to the perimeter of a standard circular gobo. These add-on
gobo probes are very handy in chasing down just where these
streaks are coming through. I used whittled-down small wooden
clothespins to hold these patches to the gobos. (I refer to the
clothespins as precision spring clamps to keep people from
thinking my work is unsophisticated, and I call these patches
hitchhikers. In part, because of the issue of these secondary
reflections, I have become very selective about my glassware.
Today I use only hand-blown glassware and Corning's Pyrex.)
While these photos required a lot of patience in the setup,
this gobo technique proved successful for photographing models in
bottles, and it should also work very well for glass cases, etc.
Remember, this procedure is not the final word. If you see a good
reason to change some of the preceding methods, go ahead; you'll
probably make an improvement.
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