Lighting Techniques for Clinical Facial Photography

Lighting Techniques for Clinical Facial Photography
Lighting Techniques for Clinical
Facial Photography
Contents
2.1
Lighting Techniques for
Clinical Facial Photography ....................
9
2.2
Equipment and Technique ......................
10
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
Discussion..................................................
Point, Line, and Plane ................................
A “Natural” Option ....................................
Problems with Two or More Lights ...........
Avoid a False Asymmetric Face.................
The Importance of Soft Box Size ...............
Avoid Shadows on the
Background Panel ......................................
Advantages of Ceiling-Mounted
Equipment ..................................................
12
13
13
13
14
14
14
The Seven Rules of Multiple Shots .........
15
References ...............................................................
15
2.3.7
2.4
14
2
Several times we have observed my colleagues
getting annoyed because of a less-than-perfect
result obtained with the latest high-ended camera. What are the weak points in clinical facial
photography? The principal variables are the type
of camera, the quality of the lighting, the lenses,
the film (or the CCD), the background panel,
patient positioning, and camera positioning
(framing) during the photographic shoot.
Additional important steps are film developing
and printing, as well as picture storage.
After years of direct experience and commitment, I am convinced that the most demanding
aspects of clinical photography are patient lighting, the topic of this chapter, and patient positioning and framing, which is discussed in Chap. 3.
2.1
Lighting Techniques for
Clinical Facial Photography1
The taking of clinical photographs, to record and
to utilize during surgery, is an essential part of the
activities of every professional practice or facial
surgery department. The narrowness of the office,
the cost of the equipment, and a vague lack of
time do not constitute excuses for less precise
patient documentation.
To obtain the best quality and consistency of
results, many suggest the use of a professional
lighting system composed of two or more flash
1
Adapted from [5]
F. Meneghini, P. Biondi, Clinical Facial Analysis,
DOI 10.1007/978-3-642-27228-8_2, © Springer-Verlag Berlin Heidelberg 2012
9
10
2
Lighting Techniques for Clinical Facial Photography
Fig. 2.1 Photographic set.
The patient holds, with her
hands, a small rectangular
reflecting panel positioned
horizontally against the chest,
just under the collarbone. The
operator easily adjusts the
monolight vertically and
horizontally
units. Thus, an entire room or a large part of it
should be permanently reserved for this use.
In the past 8 years, I have utilized a system of
lighting based on a unique source of light (monolight flash), which is ceiling-mounted in a corner
of a room also dedicated for other activities, with
good results. This chapter presents a description
of the key technical points and the rationale for
using single-light equipment. All the clinical
facial photographs that illustrate this book have
been obtained utilizing this lighting system.
2.2
Equipment and Technique
The studio lighting equipment consists of a single professional flash (System 300 professional
compact flash by System Imaging Ltd, UK),
which is ceiling mounted on a straight rail parallel to the background panel. The total length of
the rail is 0.95 m. The distance of the flash unit
from the background is fixed at 1.6 m. A pantograph (Friction Pantograph 3250 by I.F.F.,
Calenzano–Firenze) holds the monolight and
allows unrestricted vertical adjustment. A rectangular 0.75 × 0.35 m soft box (75 Light Bank
by System Imaging Ltd, UK) fits on the flash
unit, softening and diffusing the light. An alternative smaller and more practical soft box,
0.4 × 0.3 m (Chimera Lightbanks, Boulder,
Colorado, USA), has also been utilized during
the past 5 years.
The distance from the monolight to the subject
is fixed (about 1.1–1.2 m), so each photograph is
taken at the same F-stop of 16 with 100 ISO films.
The lighting is directed toward the subject in
all views, maintaining the flash unit at a higher
level. The rectangular soft box is held in a horizontal position.
In order to eliminate the problem of shadows
on the submental region and under the nasal base,
the patient holds, with her hands, a small rectangular reflecting panel of 0.35 × 0.7 m (Fig. 2.1).
This panel is positioned horizontally against the
chest, just under the collarbone.
The ceiling-mounted rail allows the adjustment of the monolight to a side or central position
(Fig. 2.1). It easily follows the rotation of the subject from the frontal to oblique and lateral views.
Figure 2.2 shows the basic positions of the flash
unit used in the different views to achieve the best
results. An important rule is to maintain the subject’s position close to the background panel itself
in order to avoid the need for an adjunctive flash
unit to light the background panel.
For a routine set of photographs consisting of
full-face portraits and closeup views, I use the
105 mm Micro-Nikkor lens.
2.2
Equipment and Technique
Fig. 2.2 The three main patient/monolight positions utilized to capture the various facial views
I personally do not use a camera tripod for stability because of the very short time of light emission by the flash unit; focusing is done by moving
the camera back and forth. A camera tripod also
interferes with the positioning of the monolight and
the patient’s head. In almost every case, I directly
help the patient during positioning, touching her
chin with my hand (Fig. 2.3). On the other hand, a
11
viewfinder grid screen is highly recommended to
help the surgeon orient the camera precisely.
To avoid using a direct wire connection to the
monolight, a small on-camera electronic flash,
oriented in a reverse direction, gives the input to
the built-in slave unit of the main flash.
The space reserved for clinical photography in
the room is rather narrow, as illustrated in Fig. 1.1
of the previous chapter.
Due to the combination of movements permitted by the pantograph and the ceiling-mounted rail,
the flash unit can be easily positioned high up, near
the ceiling and on the left wall of the room when
not in use to leave space for other activities.
The blue background panel, 0.95 m wide and
1.10 m high, is made from a sheet of plastic material for outdoor use. An advantage of this panel is
that it is washable without running the risk of losing or changing the color.
The patient and I sit on rotating stools with
rollers. The chairs are easily adjusted in the vertical position in order to maintain the subject and
the camera at the same height during the capture
of the images.
I usually take my clinical photographs personally, without the aid of an assistant, and the entire
procedure requires no more than 5 min. For better
efficiency and to save time, I follow a specific
sequence:
• I ask the patient to meet me in the photo area, turn
on the monolight, instruct her on how to use the
reflecting panel correctly, and adjust her height
on the stool, close to the blue background panel.
• I pick up my camera, turn on the small on-camera electronic flash, and set the standard time/
diaphragm couple of 1/125 s–F16 with the
monolight adjusted to full-power light emission.
• I shoot the frontal view first, with the patient
and the flash unit oriented, as in Fig. 2.2 (top).
• I position the patient’s head for the extended
and basal views and take the photographs. The
position of the monolight remains unchanged.
• I position the patient for the right oblique views,
taking care to maintain her close to the blue
background panel. The monolight is oriented, as
in Fig. 2.2 (central), and the photos are taken.
• I position the patient for the right profile view,
taking care to maintain her close to the
blue background panel, and shoot the photo.
12
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Lighting Techniques for Clinical Facial Photography
Fig. 2.3 Positioning of the
patient’s head
The position of the flash unit remains
unchanged, as depicted in Fig. 2.2 (bottom).
• I repeat the two latter steps for the left oblique
and profile views, orienting the patient’s head
and the monolight consequently.
During the procedure, I help the patient to
assume a relaxed face and no smile, if indicated.
For each view, I systematically take at least two
shots to reduce the possibility of photos with the
eyes closed and generally to ensure a better
choice of photos later.
Currently, this lighting equipment is also used
with a digital camera (Fujifilm digital camera
FinePix S1 Pro) mounted with the 105 mm
Micro-Nikkor lens. The quality of the imaging is
fairly good, but, in this particular case, the distance between the camera and the subject for a
full-face portrait, using the 105-mm lens, is
increased to 1.5 m, due to the reduction of the
sensitive area of the CCD compared with the sensitive area of the conventional 35-mm film.
Chapter 3 shows a complete set of clinical
facial views using the equipment and technique
described above.
2.3
Discussion
In plastic surgery, photographic technique and its
standardization are an important topic, which has
been reported many times in articles and books
[3, 4, 7, 8, 15]. Clinical facial photography has
been discussed and emphasized in facial plastic
surgery [11, 12, 14] and orthodontic published
works [1, 6, 9]. The papers of some authors, such
as Ellenbogen et al. [4], Claman et al. [1], and
Sandler and Murray [9], focus on reproducible,
standardized photographs, with less advice on the
lighting technique.
Other authors, such as Zarem [15], warn of
the poor results obtained with an on-camera
single flash or a ring-light flash. The on-camera
single flash creates sharp shadows on the subject and background, so many facial details and
contours are, unfortunately, lost. A system
using a ring-light flash mounted on the frontal
element of the lens reduces the problem of
shadows on the subject but produces flat, unrealistic images and frames the subject with a
dark halo.
2.3
Discussion
The reported literature recommends having
professional studio lighting in a dedicated photo
room in order to obtain images of the highest
quality.
DiBernardino et al. [3] recommend the use of
two or more flash units and present a diagram in
which two main lights at 45° angles to the subject
are combined with two additional background
lights, again at 45° angles, to eliminate shadows in
the background. Daniel et al. [2] advise the occasional use of an additional light placed overhead to
accentuate the hair and highlight certain areas.
Many authors [2, 10, 11, 13] have investigated
lighting techniques for facial photographs in rhinoplasty patients. Daniel et al. [2] and Staffel [11],
in particular, report their observations on the
effects of different positioning of the two main
lights on the nasal tip. Both articles point out that
any changes in lighting produce a different type of
reflection. Simply by moving the lights further
laterally, increasing the angle of incidence, the
nasal tip appears more pointed, whereas an asymmetric positioning produces an asymmetric reflection on the tip, which could be mistaken for a real
anatomical asymmetry. Even in a dedicated room
for patient photography, with fixed light sources
and a camera mounted on a fixed tripod, the variable of the patient position remains.
In discussing this topic, Jack Sheen stated that
“There is no doubt that photographs can be manipulated. And lighting is probably the easiest, most
effective way to manipulate an image” [10].
Meredith [6] includes positioning the patient
too close to the background in his list of faulty
techniques that are responsible for less-than-optimal results in facial photography. In his prescription, there should be at least 0.75 m between the
back of the subject’s head and the rear wall, to
prevent shadows.
2.3.1
13
plane. Whereas the first two are positive because
they underline some characteristics of the face (for
instance, a depressed scar or a sulcus), the third is
negative, as it hides other characteristics (for
instance, the definition of the chin – neck angle).
In the same manner, the reflexes (overexposed
areas) may also be divided into three subtypes:
pointed, linear, and plane. Whereas the first two
are positive because they highlight some characteristics of the face (for instance, a pointed nasal
tip or a prominent zygomatic arch), the third is
negative, as it cancels other characteristics.
The main aim of the lighting technique developed is to produce legible images, sometimes
with points and lines.
2.3.2
A “Natural” Option
The sun is the main natural source of lighting, but
for clinical purposes, it has a weak point: its distance from the subject, in spite of its great dimensions, makes it similar to a point light source,
which, on a clear day, produces sharp shadows.
Two symmetric lights of the same power, relatively far from the subject, produce unnatural
lighting in which one corrects the shadow produced by the other’s illumination. For clinical use,
the best natural condition is a cloudy but bright
day in which the light of one source, the sun, loses
its contrast by the diffusion of the clouds, and the
softened shadows on the subject show the main
direction of the light itself. In this case, the observer
easily perceives the natural modeling effect of the
light on the surface of the face, whereas with two
symmetric lights, only the reflection of the flash in
the pupils of the eyes reveals the type of lighting
used. In other words, if the observer is aware of
the direction of the light, the reading of the images
through its soft shadows is enhanced.
Point, Line, and Plane
2.3.3
Generally speaking, a photograph may be illegible
due to underexposure (too much black) or overexposure (too much white). In clinical facial photography, the shadows (underexposed areas) may be
divided into three subtypes: pointed, linear, and
Problems with Two or More
Lights
In my personal experience, the use of two or more
flash units is counterproductive and unnecessary.
The negative aspects of a multiple light system are:
14
2
Lighting Techniques for Clinical Facial Photography
• Increased cost (almost double).
• Occupies more space.
• More complex technique (increases the parameters that potentially require adjustments).
• The effects of any single-light source are difficult to assess due to the presence of other
lights.
In a single flash system, the orientation of the
light is easily adjusted from one view to another
because the operator directly controls the shadows
and the reflection on the face with the aid of the
floodlighting. The reflecting panel, held by the
patient, does not require any adjustment during
the change from one view to another (keep the
variables to a minimum!).
particular, the large light banks (0.75 × 0.35 m)
produce softer light and, because of their wide
and homogeneous lighting, permit easy subject
positioning. The small light banks (0.30 × 0.40 m),
on the contrary, produce harder light and enhance
the texture of the skin, and it is difficult to obtain
the ideal position because the area covered with
homogeneous light is smaller, and there is an
increased likelihood of undesired shadows.
With the same emission power and distance
from flash to subject, the smaller light bank also
provides higher intensity and hence greater depth
of field (the range within which objects are in
focus).
2.3.6
2.3.4
Avoid a False Asymmetric Face
The main views used to confirm or exclude the
presence of facial asymmetry are frontal,
extended, and basal. For that reason, any differences in side-to-side lighting during the shooting
of these particular images may produce an erroneous conclusion. In any system, using two main
lights, the power output of the two units, the type
of soft boxes utilized, the orientation, the distance
from the subject, the angles of incidence, and the
height of the tripods must be identical. In other
words, six different parameters set on the right
unit must be reproduced exactly on the left. Any
deviation from a perfect equilibrium produces a
false asymmetric patient or changes the appreciation of a true asymmetry.
With my approach to lighting, symmetry is
easily achievable in frontal, extended, and basal
views, positioning the monolight directly in front
of the subject at a higher level and asking the
patient to hold the reflecting panel horizontally
against her chest, just under the collarbone. In
each case, the camera must be positioned perfectly frontal to the subject.
2.3.5
The Importance of Soft Box Size
The selection of the size of the soft box has repercussions on the quality and the ease of use. In
Avoid Shadows on the
Background Panel
Meredith’s assertion that there is at least 0.75 m
between the back of the subject’s head and the rear
wall to prevent shadows [6] is a misconception
caused by poor lighting technique. If the light source
is positioned too far from the subject, a sharp
shadow is created on the background, even with a
large soft box or umbrella to diffuse the light.
In summary, the keys to avoiding shadows are:
• Bring the flash near to the subject and the
background.
• Diffuse the light with a 0.30 × 0.40 m or wider
soft box.
• Use a reflecting panel under the face.
2.3.7
Advantages of Ceiling-Mounted
Equipment
The advantages of ceiling-mounted equipment
are sound. The floor is completely free of
cables, tripod, stands, or other objects. The
pantograph and rail system permit unrestricted
horizontal and vertical movement of the monolight, while maintaining a relatively fixed distance from the subject and the background.
Access to the area is easier for the patient, and
at the end of the procedure, the equipment can
be set aside to gain space for other activities in
a few seconds.
References
2.4
The Seven Rules of Multiple
Shots
1. Document every new patient with multiple
shots whether or not she will be treated later.
2. Multiple shots of the same view ensure that if
the patient blinks, you have plenty of nonblinking shots to choose from.
3. Multiple shots assure a better choice later.
4. After a rigorous capture of the standard view
set, if you wish, perform multiple shots to
document, in a personalized manner and without restrictions, the features of the face.
5. Use the skin marker to point out any particular
deformity or lesion and perform multiple shots
from different points of view to avoid shadows
and reflections.
6. During capture of the full-face oblique view
and full-face basal view, perform multiple
shots in conjunction with small differences in
head position.
7. Today, with digital cameras, the extra cost of
multiple shots is small (one or 100 shots cost
roughly the same). The methodology for better
documentation must be cultivated daily, applying the seven rules of multiple shots, which
also help to develop greater photographic
skills. Clinical facial photography is, in a large
part, a rigorous procedure, which requires a
protocol to assure clarity and consistency, but,
unfortunately, it is also, in a small part, an art.
References
1. Claman L, Paqtton D, Rashid R (1990) Standardized
portrait photography for dental patients. Am J Orthod
Dentofacial Orthop 98:197
2. Daniel RK, Hodgson J, Lambros VS (1990) Rhinoplasty:
the light reflexes. Plast Reconstr Surg 85:859
15
3. DiBernardino BE, Adams RL, Krause J, Fiorillo MA,
Gheradini G (1998) Photographic standards in plastic
surgery. Plast Reconstr Surg 102:559
4. Ellenbogen R, Jankauskas S, Collini FJ (1990)
Achieving standardized photographs in aesthetic surgery. Plast Reconstr Surg 86:955
5. Meneghini F (2001) Clinical facial photography in a
small office: lighting equipment and technique.
Aesthetic Plast Surg 25:299–306
6. Meredith G (1997) Facial photography for the orthodontic office. Am J Orthod Dentofacial Orthop
111:463
7. Morello DC, Converse JM, Allen D (1977) Making
uniform photographic records in plastic surgery. Plast
Reconstr Surg 59:366
8. Nelson GD, Krause JL (eds) (1988) Clinical photography in plastic surgery. Little, Brown and Company,
Boston/Toronto
9. Sandler J, Murray A (1997) Clinical photography in
orthodontics. J Clin Orthod 31:729
10. Sheen JH (1990) Discussion to: Daniel RK, Hodgson
J, Lambros VS. Rhinoplasty: the light reflexes. Plast
Reconstr Surg 85:867
11. Staffel JG (1997) Photo documentation in rhinoplasty.
Facial Plast Surg 13:317
12. Tardy ME Jr, Thomas JR (1995) Facial aesthetic surgery, 1st edn, Year book. Mosby, St. Louis, pp
94–123
13. Tebbetts JB (1998) Photography and computerassisted imaging in rhinoplasty – appendix B. In:
Primary rhinoplasty. A new approach to the logic and
the techniques. Mosby, St. Louis, p 581
14. Thomas JR, Tardy ME Jr, Prezekop H (1980) Uniform
photographic documentation in facial plastic surgery.
Otolaryngol Clin North Am 13:367
15. Zarem HA (1984) Standard of photography. Plast
Reconstr Surg 74:137
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