Note: Descriptions are shown in the official language in which they were submitted.
WO 95106273 PCT/GB94tO1828
~16983~
ILL~lMTNATING SUBJECTS FOR CTNF~MA'rOGRAPEIY
AND THE LII~E
The invention relates to the field of lighting effects
for use in illuminating photographic and cinematographic
subjects or the like. In one aspect, the invention
relates to the provision of arbitrary patterns of light
and/or shadow by means of a masking and/or filtering
arrangement placed in front of a light source. In
another aspect, the invention relates to lighting with
a selection of filters and masks, for example coloured
gels, diffusers, shadow masks and the like. In a third
aspect the invention relates to receptacles for
accessories used, by way of example only, in photographic
and motion picture studios.
Specific shaped patterns of light and shadow and similar
effects are frequently required in the lighting of
photographic and cinematographic scenes (see Fig. 1).
Other applications in theatre, exhibitions, and so on
will be apparent. A discussion of current techniques in
this field can be found in various books, for example
"Basic Lighting Worktext for Eilm and ~ideo~' by
Richard K Ferncase (Focal Press 1992, ISBN 0-240-8008S-0)
and in "The American Cinematographer". To define each
W095/06273 PCT/GB94/01828
21 69~30
lighting effect traditionally has required a lot of time
and effort on the part of lighting technicians,
carpenters and so on, and the techniques used have not
afforded much flexibility in practice. Any change in the
lighting pattern has traditionally involved a lengthy
period of waiting for a new shadow filter to be built
and/or re-positioned, while such idle time in the
production schedule can prove very expensive.
In particular, even relatively simple shadow patterns
have traditionally required the construction of special
sheets of wood with appropriate outlines and cut-outs,
with stands to position them. Simpler patterns have been
achieved using a collection of two or three basic wooden
shapes (known in the art as "flags" or "slats"), mounted
individually on stands and carefully positioned with
respect to the scene, the light source and each other,
to achieve the desired composite effect.
Any of these processes is known to be very time consuming
and therefore expensive, particularly if changes are
required once shooting has begun.
In a first aspect, the invention provides~a system
comprising a collection of elementary masking shapes and
a transparent frame or other support means by which a
W095l06273 PCT/GB94/01828
~ 2 1 6~Q
selection of said shapes can be supported in the path of
a light beam. This system can allow a desired composite
shadow shape to be composed freely, without the need to
support each elementary shape individually, or to create
a specially-shaped element from wood or the like. At the
same time, the shadow of the supporting means itself can
be made invisible.
In some particular embodiments of the invention, shapes
of opaque magnetic material are supported in any desired
orientation and combination on a transparent but magnetic
screen, placed in front of the light source. Such a
system can be set up very quickly and re-configured again
and again as desired, saving time and money in the
production schedule and reducing the need for compromise.
Other embodiments of the invention feature a frame with
magnetic or other fixing material surrounding the light
beam, whereby metal or other shapes can be positioned
across the light beam, and/or transparent film with pre-
printed shadow shapes can be mounted. The frame can be
entirely open, but may also hold coloured or neutral
density filter gels, and a transparent magnetic screen,
as desired.
Where a magnetic or ferromagnetic, transparent screen is
provided, this may be done for example by means of a fine
W095/06273 PCT/GB94/01828
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6~830
steel mesh. The steel mesh may be freely suspended by
being held taut across a frame, and/or may be bonded to
a transparent plastic or glass sheet. Of course other,
non-magnetic means of adhesion may be employed, including
hooks, suckers and self-adhesive elements (including
vacuum or friction adhesion between suitably selected
plastic materials), as an alternative or in addition to
the magnetic adhesion mentioned above. Hook and loop
fabric (for example Velcro (TM)) may also be of use,
particularly around the periphery or frame of the
apparatus.
In a second aspect, the invention provides an apparatus
comprising a frame or other support means and a plurality
of filter gels, pre-printed masks or like elements, so
that various desired permutations of coloured filters,
diffusers, shadow patterns and so forth can be
conveniently selected and mounted in the beam of a light
source. The provision of a set of various re-usable
shadow patterns is particularly advantageous. The frame
may also support repositionable shadow casting shapes,
in accordance with the first aspect of the invention.
Alternatively, one of the filter elements may include a
transparent screen suitable for magnetic or other
attachment of shape elements.
Where pre-printed and/or coloured flexible sheets are
WO9S/06273 PCT/GB94/01828
21 6 98~
.
included in the system, a quiver, rack or similar
receptacle may be provided, either freely standing or
attached to part of the system, so that a selection of
such sheets are immediately to hand, while being stored
and protected for transportation and re-use.
A further aspect of the invention provides a receptacle
for lighting accessories or the like, which includes
channel or tube suitable for surrounding the upright of
a lamp stand or the like.
By this means, the receptacle can be mounted conveniently
to hand when the accessories are in use. This improves
lS speed and flexibility of operation, and can afford better
protection in practice than a receptacle which is not
readily to hand. The receptacle can be demountable, for
example, by hinged construction. The receptacle can be
used as the quiver described above, but can also be used
in fields of application remote from cinematography and
theatre lighting.
The invention also provides methods of making still and
motion picture recordings employing any aspect of the
invention as set forth above, and to still-or motion
picture recordings wherein scenes have been lit by use
of such methods.
W095106273 PCT/GB94101828
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Embodiments of the invention will now be described, by
way of example, with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. l shows a film set with a specific shape of lighting
effect screen in use.
Fig. 2 shows an embodiment of the invention suitable for
use on the film set of Fig. l.
Fig. 3 shows a cross-sectional view along the line A-A'
in Fig. 2.
Fig. 4 shows a system of parts forming an embodiment of
the invention.
Fig. 5 is a magnified view of a part of a magnetic screen
device suitable for implementing the systems of Figs. 2
and 4.
Fig. 6 shows a cross-sectional view along the line B-B'
in one embodiment of the device of Fig. 5.
Fig. 7 shows a cross-section of the device ~of Fig. 5
according to an alternative embodiment.
W095l06273 PCT/GB94/01828
~ 2 1 6 9~30
Figs. 8 to 12 show various modifications of embodiments
of the invention.
Fig. 13 illustrates a flexible pre-printed filter sheet
for use with embodiments of the invention.
Fig. 14 shows a quiver suitable for holding various pre-
printed sheets of the type shown in Fig. 13.
Fig. 15 shows a selection of pre-printed filter patterns.
Fig. 16 illustrates an alternative class of embodiment,
in which a desired lighting pattern is created by
reflection.
Fig. 17 illustrates another system of parts forming an
embodiment of the invention.
.
Fig. 18 shows in detail two parts of the system of Fig.
17.
Fig. 19 illustrates various re-usable rigidified filters
compatible with the system of Fig. 17.
Fig. 20 illustrates the use of re-usable flexi~le filter
sheets in the system of Fig. 17.
Wog~/06273 PCT/GB94/01828
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DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
The film set of Fig. 1 features flat pieces of scenery
10, 12, 14 and so on, representing the walls of a room
where action is to take place. A camera 16 views the
room.
A bright light source 18 upon a stand 20 illuminates one
wall 10 of the room in order to create a special lighting
effect. Specifically, it is desired to cast patches of
light at positions 22 to 28 on the wall, to simulate
sunlight shining through a window somewhere outside the
field of view of the camera 16. To this end, a
specifically shaped filter, mask or ~flag" 30 has been
constructed and placed on the stand 32 in front of the
light source 18. The light source 18 is provided in a
conventional manner with flaps 34 etc which can be
adjusted to direct the light through the filter 30.
In conventional practice, it is known that the
construction of the specific shaped flag 30 will employ
electricians and carpenters to specify and create the
required cut-outs 36 etc in a piece of board 38, and to
mount this on a stand in a suitable position and
orientation. A similar effect can be achieved by use of
a transparent plastic sheet, masked in the desired
pattern by strips of black paper tape. Either way, the
conventional processes are wasteful and time-consuming.
~: =
W095/06273 PCT/GB94/01828
~ 21 6~830
It is also common practice, where simpler shadow shapes
are required, to use single pieces of wood or whatever,
held up on adjustable stands in front of the light 18,
but the known stands are unwieldy and can be difficult
to adjust.
As shown in Figs. 2 and 3, a system to be described
herein allows for the construction of simple or complex
shadow shapes from simple elements, without the need for
individual stands for these elements and/or the need for
specific carpentry operations. The flexibility and time
saving achieved can be very significant, particularly
when one considers that time wasted on a film set can
often cost tens or hundreds of thousands of pounds per
day.
The device of Figs. 2 and 3 comprises a frame 50 and a
screen 52 which is substantially transparent, in the
sense that it casts no visible shadow of itself at the
relevant distance. The screen 52 on the other hand does
provide a support for various rectangular pieces of
opaque material 54 to 64, which can be arranged on the
sheet and frame in any desired position. From this it
can be seen that the desired window shape comprising four
rectangular apertures can be constructed as shawn in Fig.
2 very quickly, and can be adjusted (66, 68) in any
dimension according to the will of the cinematographer.
W095l06273 PCT/GB94101828
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6q~3
Fig. 3 shows a device in cross-section along the line
marked A-A' in Fig. 2. It should be appreciated that the
drawing is not to scale, so that, for example, the
thickness of the transparent screen 52 and the various
elements 56, 58, 60 and 64 have been exaggerated for
clarity. Arrows 70' and 72' show light passing through
the apertures 70 and 72 (see Fig. 2) respectively. On
the other hand, arrows 56', 58' and 60' show light which
is blocked by the opacity of the elements 56, 58 and 60
respectively.
In one class of embodiments, the elements 54 to 64 are
made of flexible magnetic sheet, such as is widely
available (for example under trade name FLEXOR from
Magnet Applications Ltd., Hertfordshire, United Kingdom),
while a fine mesh of ferromagnetic metal (not shown in
Fig. 3) is bonded to the surface of the transparent sheet
52. The element 64, seen at a distance in the cross-
sectional view, can be seen to flex sufficiently that it
adheres to the screen 52 in between the other elements
56, 58 and 60, while riding up over those elements when
need be. Again it should be noted that the thicknesses
of various sheets and elements are not represented to
scale, being greatly exaggerated in Fig. 3. Both the
screen 52 and the magnetic elements are made able to
withstand the high temperatures (for example up to 110C)
that can arise in front of a powerful light source.
W095l06273 2 1 6 ~ 8 3 o PCT/GB94/01828
*
Fig. 4 shows a particular embodiment of the invention.
A large frame and sheet 80 has a width of lm and a length
of 1.33m and has a standard knuckle clamp or similar
attachment 81 for a stand. A smaller sheet 82 has a
dimension of 0.5m x 0.6m, and another standard attachment
83 is provided. Magnetic elements 84 to 90 are provided
in various types and sizes, but in this example each has
the form of a rectangle hinged at two places 85 across
its width, so that it can be folded into thinner
rectangles.
For example, the element 84 comprises opaque magnetic
plastic sheet of lm long by 0.3m wide. The sheet may be
for example between 1 and 5mm thick, depending on desired
properties. The tape hinges 85 divide the sheet 84 into
three O.lm strips. This allows an element of lm by O.lm,
lm by 0.2m, or lm by 0.3m to be deployed according to
requirements, very quickly and simply. Similarly, the
element 86 comprises three tape-hinged slats of 0.05m by
0.66m.
The elements 88 and 90 are dimensionally the same as the
elements 84 and 86 respectively, but are formed of
material which is not completely opaque, but rather
provides 0.6 neutral density (ND) filtering. ~Of course
other dimensions and other shapes of elements are often
going to be desirable, and a large kit of elements of
W095/0627~ PCT/GB94/01828
6q 830 12
various geometrical shapes can easily be provided using
known materials. The neutral density sheeting is not in
itself magnetic, but has metal bound edges, whereby it
can be fastened to the magnetic frame.
S
Fig. 5 illustrates the construction of the transparent
magnetic screen 52 in more detail. Quite simply, this
comprises a steel mesh 100 with diamond shaped apertures
102 allowing the light to-pass through. The thickness
of the wires of the mesh 100 has been exaggerated in the
drawing, while in practice, 90~ or more of the total
screen area is within the apertures 102 etc. An opaque
magnetic element 104 is attached by its magnetism to the
metal screen 100, so as to define a triangular element
of the desired shadow.
When a shadow is cast to any significant distance, the
shadow of the mesh 100 is not visible, so that the
triangular element casts a shadow in isolation, without
visible means of support. A number of arbitrarily shaped
elements can be attached to the sheet 52.
Fig. 6 shows the detail of Fig. 5 in cross-section, along
the cross-sectional line B-B'. A transparent glass or
plastic sheet 106 is provided as a substrate, to which
the ferromagnetic mesh 100 has been bonded. In Fig. 7,
on the other hand, the me$h is suspended without a
W095l06273 PCT/GB94/01828
~ 216q830
transparent substrate sheet. This has the advantage that
wind can pass through the mesh and reduce the windage of
the device as a whole, while by choosing suitable mesh
dimensions and material, sufficient rigidity can be
assured nonetheless. For example, for a mesh 100
supported by a rectangular wooden frame (not shown in
Figs. 5 or 7), it has been found that a suitable material
is 19 gauge (lmm) twill weld mild steel wire mesh with
a pitch of between one and several centimetres. The
wires of mesh may be round in cross-section, but
flattened faces as shown in the drawings provide better
adhesion. Alternatively, the mesh may be made by
stamping out of a flat sheet. Elements can also be
hooked or clipped onto the mesh, where magnetic adhesion
is not feasible or desired.
Figs. 8 to 12 show further modifications and embodiments,
which can be used in various permutations. Reference
numerals used in these drawings are broadly the same as
those used for corresponding features in the embodiments
described above. In Fig. 8, for example, a transparent
screen 52 is provided within a frame 50, and magnetic
shaped elements can be attached anywhere on this sheet
as desired. In addition, however, magnetic strips 110
and 112 are mounted around the front and rear faces of
the frame, to allow the mounting of heavier metal shaped
elements, and/or flexible plastic transparencies with
-
W095/06273 PCT/GB94/01828
~ ~qa3~
14
pre-printed shadow patterns. The drawing shows one such
transparency 114 held against the sheet by placing small
ferromagnetic pieces 116 etc where they will be held by
the magnetic strip 110 inset into the front of the frame
50.
In Fig. 9, the screen 52 (including mesh 100) is omitted,
leaving only a frame 50 with magnetic strip 110. The
flexible sheet and other metal shape elements can be
placed in arbitrary orientations as with the embodiment
of Fig. 8, subject only to the requirement that they
should meet the frame. Thus the pattern illustrated in
Fig. 2 is perfectly feasible, while it would not be
possible to mount a shape in isolation in the middle of
the screen area, as was possible with the triangular
shape 104 in Fig. 5.
Fig. 10 shows an alternative embodiment in which shape
elements can be mounted in isolation from the frame.
20 Here a transparent sheet 120 is attached to a frame 122,
without necessarily having any magnetic properties. A
set of opaque shaped elements such as the one illustrated
at 124 are provided, each one having one or more suckers
126 on its rear side for attaching it adjustably to the
25 sheet 120.
Fig. 11 shows an embodiment also including a plastic
WO95/0627~ PCT/GB94/01828
2 1 6 9830
sheet 130 which is transparent and also is sufficiently
stiff not to require a frame. Arbitrary shaped elements
132 and 134 can be attached to the screen 130. The shape
elements 132 and 134 may be attached magnetically, by
suction, or by any form of adhesion desired. For some
applications, it may even be tolerable that the adhesive
is not removable, so that the elements 132 and 134 cannot
be repositioned. Self-adhesive materials are widely
available which may be used for this purpose, including
materials with suction or friction (electrostatic)
adhesion. At the same time, it is not necessary that all
of the shaped elements employed are completely opaque.
For example in Fig. 11, shaped element 132 is opaque,
while shaped element 134 is partially transparent, being
formed either from a neutral density filter material, or
from a coloured filter material.
Fig. 12 shows a modification of the frame 50 of various
embodiments described above, such that channels or
grooves 136 are provided along opposite inwardly facing
sides of the frame. This permits rigid or semi-rigid
sheets of filter material to be slipped into place, in
addition to any shapes which are mounted on the face of
the device. The grooves may be useful, for example, for
receiving a coloured gel to give overall colour to the
light pattern, or a neutral density gel to darken the
pattern slightly. A plastic or glass sheet may also be
W095106273 PCT/GB94101828
~ ~,q~3~
16
inserted and painted by hand or spray can, if desired.
Other filters of interest may include diffusers made of
netting ("scrims~), fresnel lenses and the like.
On the other hsnd, such grooves may also be provided for
removing and replacing the magnetic screen 52 itself into
a frame. Thus, for example the device of the type shown
in Fig. 8 can be transformed quickly into a device of the
open-frame type, shown in Fig. 9.
Another type of embodiment is possible, for example, in
which shaped elements are held not against the front
surface of the device, but rather are sandwiched between
two parts of the frame, for example by spring pressure.
There may even be provided a sandwich of two transparent
sheets held together in some manner, such that shaped
pieces can be suspended in the middle of the aperture
without being supported directly by the frame.
In embodiments of this type in which it is necessary to
separate the two sheets or two frame pieces to re-
position shape elements, it may be necessary to de-mount
the device and lay it in a horizontal position, open the
two parts of the frame, adjust the shaped elements, and
finally re-close the frame pieces, before re-m~unting the
assembly in its vertical position. Disadvantages are
evident in such an embodiment, but other advantages may
W095l06273 PCTtGB94/01828
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be found, for example in cheapness of materials, such
that the relative inconvenience might be tolerated.
Figs. 13, 14 and 15 illustrate the provision of a number
of flexible, pre-printed sheets which can be used to
provide specific complex shadow patterns. In Fig. 13,
a flexible sheet 138 is transparent except for an opaque
pattern 140 printed upon it. The transparent sheet can
be employed as the sheet 114 in the embodiments of Figs.
8 and 9. For greater convenience, the transparency 138
is provided with metal or magnetic strips 142 and 144,
to avoid the need for separate pieces of metal or magnets
(116 in Figs. 8 and 9). Alternatively, hook-and-loop
fabric (Velcro (TM)) can be used in place of the strips
142 and 144, with complementary fabric mounted around the
frame 50.
Fig. 14 shows a quiver for holding a number of such
transparent sheets in a convenient and accessible manner.
In particular, the quiver body 146 houses a number of
separate tubes for rolled-up sheets, including for
example an empty tube 148, and a tube 150 which is
housing a rolled-up pre-printed transparency. Other
spaces may be adapted for receiving and storing shadow
casting shape elements.
Conveniently, such a quiver may be built into or attached
W095/06273 PCT/GB94101828
2 ~ 6~ ~3~ 18
to the stand which holds up the magnetic screen device.
For this purpose, the quiver 146 is constructed in two
halves 146A and 146B, and a hole 152 down the centre of
the quiver is adapted to surround the upright leg of the
stand of the screen device (32 in Fig. 1). The back edge
154 of the quiver is provided with a cloth hinge or
similar, joining the two halves 146A and 146B, while
Velcro (TM) or other fasteners 156 and 158 are provided
at the front edge. Undoing these fasteners 156 and 158
permits the halves to hinge apart, as indicated by the
arrow 160, so that the whole quiver can be mounted and
de-mounted on the stand. It is often a problem on the
film set that a light source is located at a remote
position. By this means, it can be assured that a full
range of gels, transparencies and the like are always to
hand. A lid and carrying handle (not shown) can be
provided on the quiver for ease of transport.
Fig. 15 shows a selection of patterns of opaque printing
on transparent sheets, which can be available on the film
set and deployed upon the screen at very short notice.
The same set of patterns can be provided in coloured or
neutral density filtering forms, to provide softer or
coloured shadows.
The provision of various general-purpose re-usable
patterns of the type shown offers great convenience
W095/06273 PCT/GB94/01828
~ 2169~30
19
compared with the conventional situation in which such
patterns are well-known to be of use, but still have to
be created specially in wood or on a glass sheet each
time they are needed. The possibility of experimenting
so as to try rapidly the effect of several such patterns
while shooting a scene has not hitherto been realised.
Fig. 16 illustrates the principle of yet another class
of embodiments, in which, rather than a transparent
screen, the desired shadow shape is imposed upon a
mirrored reflector. Positioning such a device may not
be so simple as for the transmissive mask embodiments,
but avoids the need to provide a transparent and yet
magnetic substrate on which the shapes are to be mounted.
Silvered plastic film having a mirror-like surface is
readily available, and this can simply be placed over a
ferromagnetic sheet or mesh in order to receive desired
shaped elements such as the rectangles 54 to 64 shown in
Fig. 2.
On the other hand, a transparent mounting device as
described in the earlier embodiments can be more
versatile, in that it can be converted to a reflective
type of device simply by the addition of a mirror sheet.
Such a sheet may be provided as one of the flexible
transparencies (138, Fig. 13) or may be provided as a
sheet for sliding into grooves provided in a frame of the
W095l06273 PCT/GB94101828
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device (136, Fig. 12). When used in transmissive mode,
the subject and light source will be on opposite sides
of the masking device, as shown in Fig. 1. On the other
hand, when a reflective type mask is employed, the light
source and subject will both be located on the same side
of the reflective masking device, as shown in Fig. 16.
Figs. 17 to 2Q illustrate another system of parts forming
an embodiment of the present invention, of the general
type described above with reference to Figs. 9 and 12.
Reference numbers similar to those used in the earlier
figures are used for simplicity.
In Fig. 17, a rigid, open frame 50 of aluminium is
mounted on a stand 170, which is telescopically
adjustable in height, by means not shown in the diagram.
Frame 50 can pivot about a horizontal axis by operation
of two pivots 172 and 174, one of which is lockable, and
can swivel about a vertical axis if desired. The frame
and pivots can be of conventional construction, and a
suitable stand is commercially available in the United
Kingdom from Arri GB, for example, under the trade mark
ARRIFLEX.
Strips 110 of magnetic sheet material such a~ FLEXORtm
are provided around the front face of the frame as shown,
and optionally around the back face (not shown). Shadow
W095l06273 PCTtGB94/01828
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21 6q830
21
casting shape elements 176, 178 and 180 made of mild
steel sheeting are provided, which are easily held
supported on the frame by the magnetic action of the
strips 110. Elements 176 and 178 comprise simple
rectangular shapes, while element 180 has a telescopic
construction, described in more detail below, with
reference to Fig. 18. This construction allows element
180 to be adjusted in length, as necessary to span the
aperture of the frame 50 at different angles, or to span
frames of different sizes. Of course, folding elements
may also be provided, as described above with reference
to Fig. 4.
Flexible sheets of filter material or pre-printed masks
can be mounted magnetically on the front or back of the
frame 50, just as described above with reference to Fig.
9. As an additional facility, however, spring clips are
also provided, as shown for example at 182 and 184. Some
possible applications for these clips will be described
below with reference to Fig. 20.
Turning to Fig. 18, an opaque rectangular shape element
178 is shown. This comprises a sheet of 24-gauge or 32-
- gauge mild steel, for example, whose edges have been
25 folded over at 178a to 178d. These folded edges provide
stiffness to the thin material, and also are less sharp
to handle. For larger elements, and/or when using
W095/06273 PCT/GB94101828
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22
thinner material, additional formations such as ribs or
corrugations can be used to improve stiffness further.
The telescopically adjustable element 180 comprises an
inner element 180A similar to element 178, and an outer
sleeve element 180B. Three edges of the outer element
180B are folded over in a box-like section, so as to fit
slidably around the inner element 180A. In the event
that further stiffening ribs are desired in this type of
element, cooperating longitudinal ribs and grooves may
be provided in the elements 180A and 180B, which may also
serve to guide the sliding elements.
Fig. 19 shows three representative elements 190, 192 and
194 for attachment on the magnetic frame 50 of Fig. 17.
Each element has a rigidifying frame 196 of heat- and
flame-resilient plastic or card-like material. On the
front face at each corner the frame is provided with a
s~uare patch of magnetic sheet material 198, while on the
rear face at each corner (199 not shown) a corresponding
patch of thin steel sheet is provided. The steel corner
patches allow each element 190 to 194 to be held against
the magnetic strips 110 of the frame 50 (Fig. 17), while
the magnetic patches 198 allow the steel patches (199)
of further elements to be engaged magnetically. In this
way a series of filter elements can all be mounted one
on top of the other in cascade on a single support
WO9Sl06273 PCT/GB94/01828
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50/110.
Magnetic corner patches 198 or entire edge strips could
be provided on both faces of the frame 196, but in
practice the adhesion between two magnetic patches is
greater than is either necessary or desirable. In
particular, it has been found preferable to use
complementary steel and magnetic patches 198/199 as
described, so that the elements 190 etc. may be easily
separated, and do not become too securely attached to one
another in storage or in use. Patches of Velcro~ could
be provided as an alternative to the magnetically
cooperating corner patches, although such fabric may be
less hard wearing than the magnetic patches.
In the element 190, a plain coloured filter gel 200 is
provided, while element 192 features a pre-printed
"ulcer" or ~cukaloris" pattern 202 for casting a dappled
light pattern. The elements 190 and 192 can be combined
and mounted on the single stand 170, for example, by
mating the steel corner patches (199) of the element 190
with the magnetic strip 110 of the frame 50, and mating
the steel corner patches (199) of element 192 with the
magnetic corner patches 198 of element 190.
The third element 194 features a steel twill weld mesh
204 suitable for supporting shadow casting shape elements
W095/06273 PCTIGB94/01828
.
~1 6'~8
24
of magnetic sheet material. This too can be mounted in
combination with coloured gels and like elements, and
removed from the light path when not required. The
magnetic and steel patches 198/199 thus can be seen as
an alternative to the grooves 136 described above with
reference to Fig. 12.
Although the frame 50 is shown square for simplicity, a
hexagonal frame has been found particularly suitable,
while circular or other shapes are of course possible.
Since circular and hexagonal frames have less extreme
diagonal dimensions, it has been found that the
telescopic type of element (180) is less necessary. The
square or hexagonal type of frame can also be constructed
in knock-down form out of four or six extruded sections,
for ease of transport.
Fig. 20 shows a further alternative or additional
mounting arrangement, particularly for flexible gels or
patterned sheets which can be rolled up before and after
use, as shown in Figs. 13, 14 and 15 above. Instead of
metal or magnetic strips 142 and 144 (Fig. 13), a
flexible sheet 210 in Fig. 20 is stiffened along top and
bottom edges by a cylindrical rod 212 (top edge only
shown), which may be of wood.
Apertures 214 and 216 are provided in the sheet where it
W095l06273 PCT/GB94/01828
2 1 6 q830
meets the stiffening rod 212, and these allow the rod to
be pushed into the spring clips 182 and 184 provided on
frame 50. Furthermore, the apertures 214 and 216 lie
over a further pair of spring clips 182' and 184' mounted
on the frame 50. This further pair of clips allows a
second flexible sheet with stiffening rod 212' (shown
dotted) to be mounted on the frame over the first sheet
210. The spring clips may be made of metal, as shown,
or may be for example moulded rubber formations.
If the rods 212 are stiff enough, the spring clips can
be mounted at their ends, avoiding the need for the
apertures 214 and 216 altogether. Such rods may also be
mounted by a single spring clip at one end, if the frame
provides a ret~i n ing recess for the other end. The clips
can be mounted in a form .e.novable from the frame, to
avoid clutter when the roll-up sheets are not in use.
Therefore a variety of methods and types of element can
be provided for mounting on a frame or other support in
a wide variety of ways. Any of the embodiments described
allows the construction of complex masks and filters with
fewer stands than hitherto, and with much greater speed
and versatility.
It will be appreciated that each of the particular
mounting features or sets of accessories exemplified
W095/06273 PCT/G~94/01828
~ ~983~ ~
above is entirely optional, and that a useful and
versatile system of lighting accessories within the scope
of the invention will remain even when one or more of
these features are omitted. Similarly the range of
accessories that can be provided in the system is not
limited to the examples listed above, but covers any
light-modifying accessory that is desired to go between
a light source and a subject for illumination. Examples,
as mentioned above, include flags of various shapes,
nets, gels, diffusers, ulcer/cukaloris boards and so
forth.
Those skilled in the art will readily appreciate the
great improvement in speed, flexibility and convenience
afforded by the devices and systems described, and will
readily conceive of other modifications and embodiments
within the scope of the invention.