Abstract:
According to the invention, an LED fixture is provided for photographic and theatrical lighting. The light fixture is particularly suitable for photographic and theatrical lighting by mounting LED elements directly or indirectly on articulating arms. The arms rotate 90 degrees from a position where the arms are aligned substantially in parallel with an axis of the fixture hub and may be rotated 90 degrees for deployment of the fixture. In addition, the spokes may be flexed beyond the alignment permitted by the cooperation between the hub and mounting elements.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to lighting fixtures, and particularly to fixtures for use in still photography and cinematography. 
         [0003]    2. Description of the Related Technology 
         [0004]    Photography is the science, art, and practice of creating durable images by recording light or other electromagnetic radiation, either electronically, by means of an image sensor, or chemically, by means of a light-sensitive material such as photographic film. Still photography is the practice of making non-moving photographs, as distinct from motion picture photography (cinematography). Cinematography is the science or art of motion picture photography by recording light or other electromagnetic radiation, either electronically by means of an image sensor, or chemically, by means of a light-sensitive material such as film stock. Photographic lighting is the illumination of scenes to be photographed. A photograph may simply record patterns of light, color, and shade; lighting is important in controlling the image. In many cases even illumination is desired to give an accurate rendition of the scene. In other cases the direction, brightness, and color of light are manipulated for effect. Lighting is particularly important for establishing an interplay of highlights and shadows. Lighting and exposure are used to create effects such as low-key and high-key. 
         [0005]    The main sources of light for photography are:
       1. Natural/daylight, which varies with the weather and the time of day. Different techniques are necessary to take best advantage of or control the impact of natural light conditions, such as brilliant sunshine, an overcast evening, or any other condition;   2. Continuous artificial light, which may be normal lighting, or produced by special photoflood lights or other fixtures; and   3. A bright and very brief photographic flash from one or more positions.       
 
         [0009]    The properties of different light sources vary; household incandescent lighting, fluorescent lighting, sodium discharge street lighting, etc., are very different and produce different results, and require different correction if a subjectively neutral or other desired rendition of colors is required. 
         [0010]    Lighting creates the two dimensional pattern of contrast the brain interprets to recognize three dimensional objects in photographs. In an in-person viewing experience the brain relies on stereoscopic vision, parallax, shifting focal in addition to the clues created by the highlight and shadow patterns the light on the object creates. When viewing a photographic image the brain tries to match the patterns of contrast and color it seen to those other sensory memories. 
         [0011]    The baseline for what seems “normal” in lighting is the direction and character of natural and artificial sources and the context provided by other clues. In the example the photographer added a warming gel on the flash of the woman standing in a field in late afternoon light. The viewer knows the time of day from the angle of the shadows and neutral color balance would have seemed odd in that context. But similarly the image of the woman if masked out and put on a plain white or neutral gray background would seem abnormally yellow. 
         [0012]    The goal in all photographs is not necessarily to create an impression of normality. A lighting strategy can be used to achieve an impression that is different than normally expected. Light direction relative to the camera can alter the appearance of a three dimensional object to give a two-dimensional impression. The presence, position, size/length, and direction of highlights and shadows provide other clues to shape and, when outdoors, the time of day. The tone and length of shadows provide contextual clues about the time of day or environment and by inference, based on personal experience, the mood of person. 
         [0013]    A skilled photographer can manipulate how a viewer is likely to react to the content of a still or moving photograph by manipulating the lighting. In outdoor photography that can require a change in location, waiting for the ideal time (angle of sunlight) of day or in some cases the ideal time of year for the lighting to create the desired impression in the photograph or manipulating the natural lighting by using reflectors or flash. One of the limits to options for lighting objects to make a photographic image look “seen by eye” normal or surreal as a goal for the photograph is the available equipment. The viewer&#39;s reaction to an image(s) will be from the baseline of whether the lighting seems normal/natural or not compared to other clues. For example, when mixing natural artificial lighting, it is possible to control the differences between the shadow clues from the artificial light in coordination to the natural light. A photograph of a person&#39;s face artificially illuminated to appear as if it were photographed at noon will not seem normal if the background is illuminated by a setting sun because the lighting clues of the foreground do not match. 
         [0014]    The sun hitting the front of objects facing a camera acts as “key” light creating highlights and casting shadows. The detail in the shadows is visible because the sunlight reflects off water vapor and dust in the atmosphere creating omni-directional “fill”. In open shade three dimensional objects will also usually cast shadows because the downward vector of skylight is usually stronger than the sideways vectors illuminating the sides. When a photographer puts a light source behind an object its role in the lighting strategy is to define an outline and create an impression of physical separation and three dimensional space that a frontally illuminated scene lacks. To differentiate that role from that of “key” modeling when a modeling source moves behind the object it is typically called a “rim” or “accent” light. In portrait lighting it also called a “hair” light because it is used to create the appearance of physical separation between the subject&#39;s head and background. In natural lighting the tone of the background of an image is influenced by its reflective qualities and whether it is illuminated by the sun directly or skylight indirectly. Either the sun or sky, or a combination of both can be used for “background” lighting. 
         [0015]    Artificial lighting strategies which seem most “natural” duplicate the same contrast pattern clues seen on three dimensional objects in various lighting conditions. A typical studio lighting configuration will consist of a fill source to control shadow tone, a single frontal key light to create the highlight modeling clues on the front of an object facing the camera over the shadows the fill illuminates, one or more rim/accent lights to create separation between foreground and background, and one or more background lights to control the tone of the background and separation between it and the foreground. This equipment may be cumbersome to store or transport. 
         [0016]    There are two significant differences between natural lighting and artificial sources. One is the character of the fill and the other is more rapid fall-off in intensity. In nature skylight fill is omni-directional and usually brighter from above. That “wrap around” characteristic is difficult to duplicate with a directional artificial source. In a fixed studio location it is possible to bounce fill backwards off a white wall to flood the space with indirect reflected light to simulate the impression of the sun reflecting off the atmosphere. Another way is to supplement a fill source from the direction of the camera with reflectors placed near the sides of the foreground subject. 
         [0017]    The inverse-square law describes the approximate way a light source radiates and changes in intensity with distance. As the distance from a source doubles the area of the footprint of light increase by a factor four (the square of the distance). Because the same number of photons are spread over four times the area when distance is doubled the intensity at any point will be or ¼ the strength. Photographic light sources are not point light sources so the inverse square law does not perfectly apply but it explains why distance of artificial sources affects the character of lighting and lighting strategies in ways not seen in nature. 
         [0018]    According to the inverse-square law if the distance of a light source is changed in the following distance increments 1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45, 64 the intensity will decrease by one f/stop. In practical terms this means if one face in a group portrait is 4 m from the “key” light and another is 5.6 m away the face further from the light will be one f/stop darker. In an outdoor portrait of a group of 200 people taken on an overcast day the lighting on all of the faces will be equal. The same group photographed indoors would be far more difficult to light evenly. The simplest strategy requiring the least lighting equipment would be to get above the group with the camera, have them look up and bounce the lighting off the ceiling so like an overcast day every face is as equidistant as possible to the apparent source of the light. 
         [0019]    Even something as basic as a head and shoulders portrait must take inverse-square fall-off into account by posing the front of the subject&#39;s face as close or closer to the “key” light than the shoulder or any other body part if the goal is to make the front of the face the most strongly contrasting focal point on a darker background. The position of the fill source relative to the face will also affect whether the nose shadow is the lightest (when fill is centered near camera) darkest (when fill is placed to the side) one on the face. The distance of the key and fill sources to the face will affect the rate at which the shadows transition from light to dark on the face. 
         [0020]    A scene may be lit to look natural or surreal. Natural and surreal just describe grossly the effect of lighting. Understanding what makes lighting seem natural makes it easier to understand how to create other desired reactions. Natural light usually comes from above, so strategies which place the key light below the face will appear to be unusual or unnatural. The brain adapts color perception in a way which makes color balance seem neutral on white clothing and faces. The eyes also adapt to brightness as they scan and usually perceive a full range of detail in most environments. Lighting a scene with a tonal range or color cast which is out of context with what would typically be expected will cause the viewer to notice the environment and make other than normal assumptions about it. It is also possible to create the impression of environmental context where none is seen in the photograph, such the look of a person standing under a streetlight at night by using a gridded flash attached to the ceiling of the studio with no fill source. 
         [0021]    A reflector is an improvised or specialized reflective surface used to redirect light towards a given subject or scene. Reflectors are often fixed to an artificial light source (for example, a filament bulb or flash tube) to direct and shape the otherwise scattered light by reflecting the light off a concave inner surface and direct the light toward the scene to be photographed. Although there are a large number of variants, the most common types of reflectors are spherical, short-sided, giving a relatively broad spread of light, and parabolic, providing a tighter, parallel beam of light. 
         [0022]    The reflector factor is the ratio of the illumination provided by a lamp fitted within a reflector to the illumination provided without any reflector fitted. A matte reflector will typically have a reflector factor of around 2, due to its more diffuse effect, while a polished or metallic-finished reflector may have a factor of up to 6. 
         [0023]    A Soft box is a type of photographic lighting device, one of a number of photographic soft light devices. Soft light fixtures create even and diffused light by directing light through some diffusing material, or by “bouncing” light off a second surface to diffuse the light. Light from a bulb may be bounced off the inside of a metalized umbrella to create a soft indirect light in a known umbrella light. 
         [0024]    A “soft box” is an enclosure around a bulb comprising reflective side and back walls and a diffusing material at the front of the light. 
         [0025]    The sides and back of the box are lined with a bright surface—an aluminized fabric surface or an aluminum foil, to act as an efficient reflector. In some commercially available models the diffuser is removable to allow the light to be used alone as a floodlight or with an umbrella reflector. 
         [0026]    A soft box can be used with either flash or continuous light sources such as fluorescent lamps or “hot lights” such as quartz halogen bulbs or tungsten bulbs. If soft box lights are used with “hot” light sources, the user must be sure the soft box is heat rated for the wattage of the light to which it is attached in order to avoid fire hazard. 
         [0027]    U.S. Pat. No. 3,851,164 entitled, “Umbrella Light,” is expressly incorporated by reference herein and shows a prior art umbrella light fixture. As shown in  FIG. 9 , a light source  11  is adjustably fixed to the axial shaft  12  of a foldable umbrella-type reflector  13 . The assemblage of umbrella-type reflector  13  and light source unit  11  is adjustably supported on a swivel  14  atop a conventional folding tripod stand having an adjustable telescoping vertical pole  17 . The light source unit  11  has a pair of quartz halogen lamps. 
         [0028]    The light source unit  11 , has the lamps and reflectors in predetermined fixed relationship, is adapted to be secured at any suitable position along the length of the umbrella shaft  12 . To this end it has spring clamp  32  for frictionally engaging the shaft  12 . The bulbs and their reflectors are not arranged completely symmetrically with respect to the shaft  12  and the umbrella-type reflector carried thereby. 
         [0029]    The spring clamp may be a simple conventional spring clip such as is used for holding sheets of paper together, having a pair of spring-loaded jaws generally several cm (e.g., about 5 cm) long and having a pair of finger pieces (e.g., Boston Bull Clip No. 2). One of the finger pieces is secured to the housing of the light source unit  11 ; the other, projects outwards for manual manipulation and is provided with a heat- and electrically-insulating covering. 
         [0030]    The prior art device is configured with light source unit  11  fixed to the swivel  14  such that the center of gravity of the device is situated approximately directly over the pole  17  or base of the tripod. Like conventional umbrellas, the umbrella has, on its central shaft  12 , a small ring  56  fixed near the top of the shaft; a set of long ribs  57  each having one end  58  pivotally attached to the small fixed ring  56 ; a slider  59  mounted on the shaft and having a small ring  61  integral therewith; a set of short ribs  62  each having one of its ends  63  pivotally attached to the slider ring and its other end  64  pivotally attached to the long rib at an intermediate point  66  on the length of said long rib  57  (a pivot fitting  67  being fixed to each long rib for this purpose); a latch  68  to hold the slider  59  in a position on the shaft in which the umbrella is open; a second latch  68   a  to hold the slider in a position on the shaft in which the umbrella is closed; and a fabric cover  69  which is fixed to the shaft just outside of the fixed ring  58  (being held on the shaft by a suitable ferrule  71 ) and is attached (as by suitable thread loops  72 ) to fittings  73  secured to the long ribs  57  adjacent their free ends  74 , as well as by intermediate thread loops  76  engaging intermediate portions of said long ribs. As in conventional umbrellas, the covering is made up of series of substantially identical sectors or panels sewn together along their edges, forming seams, and the rib-attaching loops  72  are situated at the outer ends of the seams so that each of the panels is disposed between the corresponding adjacent long ribs. The position of the latch  68  is such that when the slider is held thereby the fabric is taut and the long ribs are bent. The ribs are flexible and of conventional construction, of thin metal which is formed into channel-shaped cross-section over substantially their whole length, except at their ends. 
         [0031]    The umbrella is shaped so that in its open operative position it has a central portion, adjacent to its apex, whose fabric surface faces in a direction such as to reflect the light principally in an axial direction and a peripheral portion whose fabric surfaces face in a direction such as to reflect the light principally in a direction which is radial of the axis. 
         [0032]    A significant disadvantage to the prior art configurations of umbrella lights as described above, that the weight of the light source unit and the required proximity of the light source unit  11  to the umbrella reflector limits the range of positions for the fixture which must always have a center of gravity above the base of the tripod. The relative position of the pole  17  and the fabric cover limit the orientation of the umbrella type reflector. In addition, the lighting unit, long ribs, short ribs, shaft and mounting pole all interfere with the light projection. The components, particularly the light source unit  11 , contributes significant weight and the fixture is bulky, cumbersome to assemble, and requires significant storage space to store. 
       SUMMARY OF THE INVENTION 
       [0033]    It is an object of the invention to provide a versatile fixture for photographic lighting. 
         [0034]    The diversity of conditions and desired lighting effects for photography may require complex lighting strategies. It is a further object of the invention to provide a fixture that may be easily deployed and may be used, in varied situations for photographic lighting. 
         [0035]    It is a further object of the invention to provide a fixture that may be adjusted to change the color, temperature, and intensity of the light created. 
         [0036]    It is a further object of the invention to provide a lighting fixture that may be compactly stored and easily transported. 
         [0037]    It is a further object of the invention to provide a lighting fixture that is not fragile. 
         [0038]    It is a further object of the invention to provide a lighting fixture that reduces the amount of heat generated by a light source. 
         [0039]    It is a further object of the invention to provide a lighting fixture that may have a reflector. It is a further object of the invention to provide a lighting fixture that may have a cover. The cover may be reflective or may be black. According to an advantageous feature, the cover may be provided to reduce light emissions in the area outside of the direction of interest. The cover may have a range of curvature when deployed. 
         [0040]    It is a further object of the invention to provide a lighting fixture that does not require a reflector, yet is still able to effectively light an object for an exposure of at least f/1.4 at twelve feet on ISO 800 film. 
         [0041]    One or more of the objects may be achieved by fixtures according to the invention. According to an advantageous feature of the invention a light fixture for photography may have light emitting diodes as its light source. Advantageously, the LED light sources may be arranged to cast light on a subject appearing to be uniform. It is an advantageous feature to provide a fixture that is collapsible and may be stored in a small space. 
         [0042]    A fixture according to an embodiment of the invention, when assembled, may be shaped to direct light in a desired direction. The shape may be concave in the area of light emission. The light emitting portion or side of the fixture may be dish shaped. The light emitting portion of the fixture may be parabolic. The light emitting portion of the fixture may be in the general shape of a paraboloid. The shape may be paraboloidal. Description of shapes is not intended to require mathematical precision or symmetry. The scope of the invention includes a range of shapes from mathematical precision to shapes which are generally equivalent for purposes of theatrical or photographic lighting, for still or cinematographic applications. The exact shape is dependent on the characteristics of the spokes and load applied to the spokes. Light may be directed from an interior concave portion of the fixture. Advantageously the fixture may have a central hub with multiple spokes extending from the central hub. The spokes may be strips that carry a plurality of LEDs. The spokes may be pivot mounted to a central hub. Advantageously the fully assembled fixture may have the configuration of an umbrella. The LEDs may face the inside of the umbrella and toward a subject. The LEDs may be generally faced in the same direction. Advantageously the emission pattern of the LEDs may be generally normal to the mounting plane of an LED. The LEDs may have a half intensity angle of 60 degrees or less. A fixture having forward facing and emitting LEDs may not require a highly reflective backing. 
         [0043]    Advantageously, the distal ends of the spokes may be held by a band and/or a shade/reflector. The band may carry LEDs also. When the band and/or shade or reflector are disassembled from the spokes, the spokes may pivot towards the outside of the umbrella and collapse into a configuration that may be easily stored in a generally tubular shape. The distal ends of the spokes, once released, may be reversely collapsible umbrella (as compared to a conventional umbrella). 
         [0044]    A circumferential band may also carry LEDs, LED strips and/or LED packages. The LEDs may be set to be adjustable within a range of colors and temperatures. This can be accomplished by controlling individual LEDs having different colors and temperatures, or using LED elements which may be adjusted in color and/or temperature. 
         [0045]    According to an aspect of the invention a light fixture may have a central hub base with three or more spokes hinged to the hub. The hinge may have an element to limit the range of rotation of the hinge at a position suitable for deployment and use. The spokes may rotate to be positioned where they are substantially parallel to the axis of the hub. This is the storage position where the fixture is folded to be compact and may be placed in an elongated bag or tube for storage and protection during transport. To set up the fixture for use, the spokes may be opened up by rotating them, for example, by approximately 90% so that they are aligned substantially perpendicular to an axis of the fixture. The fixture may have an arrangement to limit the rotation at that orientation. The spokes may then be flexed and held in a flexed alignment for use. 
         [0046]    A plurality of LEDs may be distributed along the spokes so that LEDs define a generally concave shape or paraboloidal shape. A strap may be used to keep the spokes flexed. The LEDs may have a radiation pattern to emit light in a forward direction. This is useful when the fixture is pointing toward a photographic subject. The LEDs may be configured to emit sufficient radiation to effectively light an object for an exposure of at least f/1.4 at 12 feet on ISO 800 film. The LEDs may be mounted on an LED strip and an LED strip may be mounted on a spoke. The fixture may have LED packages mounted on the spokes. The spokes may be made with carbon fiber. The spokes and strap may be clipped or the strap may have pockets to receive the ends of the spokes. A slot and mating dog may be provided on the hinge and the hub to stabilize the spoke in relation to the hub. The fixture may have a back cover connected to the spokes in a deployed configuration. The cover may be reflective, have a high optical density, and/or be wind-permeable depending on the use. An LED controller may be provided to control the color, intensity, and/or temperature of the fixture light. The fixture may have a front cover which is a filter or diffuser. The front cover may also be clear. 
         [0047]    Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components. 
         [0048]    Moreover, the above objects and advantages of the invention are illustrative, and not exhaustive, of those that can be achieved by the invention. Thus, these and other objects and advantages of the invention will be apparent from the description herein, both as embodied herein and as modified in view of any variations which will be apparent to those skilled in the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0049]      FIG. 1  shows an illustration of an embodiment of a fixture according to the invention; 
           [0050]      FIG. 2A  shows an illustration of an embodiment of an LED strip that may be used according to an embodiment of the invention; 
           [0051]      FIG. 2B  shows an illustration of an LED package that may be used according to an embodiment of the invention. 
           [0052]      FIG. 3  shows an illustration of an embodiment of a fixture according to the invention; 
           [0053]      FIG. 4  shows an embodiment of a fixture in a storage configuration according to an embodiment of the invention; 
           [0054]      FIG. 5  shows an illustration of an embodiment of the invention in an open, but not fully deployed configuration; 
           [0055]      FIG. 6  shows an illustration of an embodiment of the invention with spokes in a deployed configuration; 
           [0056]      FIG. 7  shows a detailed illustration of a front view of a hub and spokes according to an embodiment of the invention; 
           [0057]      FIG. 8  shows a detailed illustration of back view of a hub and spokes according to an embodiment of the invention; 
           [0058]      FIG. 9  shows a prior art fixture. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0059]    Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention. 
         [0060]    Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, a limited number of the exemplary methods and materials are described herein. 
         [0061]    It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. 
         [0062]    All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present invention is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed. 
         [0063]    Before the present invention is described in further detail, it is to be understood that the invention is not limited to the particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims. 
         [0064]      FIG. 1  shows an illustration of an embodiment of the invention. A fixture  100  is illustrated with a plurality of spokes  101  extending from a central hub  102 . The spokes  101  may include a plurality of LEDs  103 . The LEDs  103  may be carried by a substrate  104 . The substrate  104  may be attached to the spokes or may itself be a spoke. The substrate  104  may have terminals  105  for application of electricity to the LEDs. The spokes  101  may be curved so as to define a concave configuration. The spokes  101  may direct light into and projecting from the concave configuration. The curvature of the concave configuration may be circular, parabolic or any other shape which provides the desired light projection and characteristics. Advantageously the position of the forward emitting LEDs  103  carried on spokes  101 , may generally define an elliptical paraboloid. The shape is dictated by the characteristics of the spokes, and loading of the spokes. Advantageously the shape defined by the LEDs, intensity of the LEDs, number of LEDs and emission pattern of the LEDs are selected to cast sufficient light to illuminate an object or area for an exposure. Advantageously the spokes  101  may be flexible and resilient. A band or retainer  117  may be used to stabilize or flex the spokes  101  in a dish-like configuration. According to an embodiment the planar radius  118  of the rough circle defined by the band is smaller than the length of the rough arc  119  that starts at the central axis of the fixture and extends along the spoke  101  to a point where the circumferential band intersects the spoke  101 . The circumferential band  117  may be a cord or webbing and may be adaptable for setting different lengths and different radius of curvature. One example, shown in  FIG. 2 , of LEDs mounted on a substrate, i.e. an LED strip  116 , that may be used is an LED LITERIBBON VHO PRO SERIES sold by Litegear, Inc. (www.litegear.com/product/let-lightribbon/vho-pro-lightribbon-led/). According to one embodiment three LED strips  116  may be mounted on each spoke  101 . Electricity may be supplied by conductors from a power supply or controller connected to one or more bus structures embedded in the hub. The strips or LEDs may be connected by leads to the bus structure. 
         [0065]    According to an alternative, LEDs may be attached directly to or embedded in the spokes  101 . The spokes  101  may be carbon fiber. Carbon fiber is selected for its high strength, flexibility, and light weight. 
         [0066]    LEDs may be in any useful configuration. An alternative to the configuration shown in  FIG. 2A  is a plurality of LED packages  301  of the type illustrated in  FIG. 2B . A package may be constructed of an LED chip  302  on a submount  303  which in turn may be located on a heatsink  301 . The LED and heatsink may be located within housing  305 . The LED chip may be protected by an encapsulant  306 . A lens  307  may be provided over the LED chip  302  and mounted on the housing  305 . A first electrode  308  may be connected by a small wire  309  to the LED chip  302 . For clarity the package is shown as a cutaway where the second electrode is not shown. The second electrode is attached to the LED chip by a wire  310 . Other LED package configurations may be used. 
         [0067]      FIG. 3  shows a fixture  106  with a cover  107 . The cover  107  may be black. The cover may be reflective but, in most embodiments, need not be. The fixture  106  may be used with or without a cover  107 . The cover  107  can be selected by the user based on color, light masking, absorbing, or reflective characteristics, and wind resistance in order to achieve a desired effect. The cover  107 , when used, may have high optical density to block rearward visible light emissions from the fixture  106 . In addition, the fixture  106  may be provided with a frontal closure (not shown) which may act as a diffuser or a filter. According to a preferred embodiment, the interior area  108  of the fixture  106  may be free of elements which would block some portion of the light. The LED elements  103  are mounted on or near the interior surface  109  of the concave fixture. According to and advantageous feature, the surface  110  of a central hub may provide additional surface area for mounting LEDs. 
         [0068]      FIG. 1  shows a fixture  106  with spokes  101  and hub  102  in an operational configuration.  FIG. 4  shows the fixture  106  folded for storage with all of the spokes  101  positioned generally in the same alignment. The configuration shown in  FIG. 4  is suitable for storage and transport and suitable inserting the fixture  106  into a storage sack or protective tube (not shown). 
         [0069]    In order to deploy the fixture  106 , the spokes  101  may be rotated about a pivot  206  (shown in  FIG. 7 ). An articulation mechanism may be configured to limit the rotation of the spokes  101 . 
         [0070]    The outwardly facing surface  101   a,  of the spokes  101  may carry the LED elements.  FIG. 5  shows the spokes  101  in a fully extended position. The spokes  101  have been rotated outwardly until the articulation limiting elements engage. In order to return the spokes  101  to the storage configuration they may be rotated in direction “A” as shown in  FIG. 5 . In order to put the fixture  106  in a deployed configuration the spokes  101  may be deflected in direction “B” as shown in  FIG. 5 . 
         [0071]      FIG. 6  shows an embodiment with spokes  101  which have been articulated to a limit and in a deployed configuration deformed so that the distal end  113  of each spoke  101  is closer to a central axis  114  (indicated in  FIG. 1 ) of the fixture  106  than the length of the spokes. For clarity,  FIG. 6  is illustrated without a circumferential retainer  117 .  FIG. 1  shows a fixture with flexible resilient spokes  101 . The distal end  113  of the spokes  101  may be held in position by a circumferential retainer  117 . The spokes  101  may be flexed and the distal end  113  of each spoke  101  may be loaded by a circumferential retainer  117 . A clip, buckle or other retaining mechanism may be used to engage the circumferential retainer  117  and the distal ends  113  of the spokes  101 . The circumferential retainer  117  may be a strap. The circumferential retainer  117  may be integrated with a cover  107 . The cover  107  may be configured to keep the distal ends  113  of the spoke  101  in the correct position without a separate strap. 
         [0072]    The hub  102  may include a rear-facing portion  111  with a mount suitable for mounting the fixture  106  on a holder  112 . The holder  112  may be in the form of a hand-held boom, a tripod or any other mechanism configured to hold the fixture in a desired location, position, or orientation. 
         [0073]    The circumferential retainer  117  may be a band which itself is a carrier surface for mounted LEDs. 
         [0074]    Utilization of many LEDs  103  mounted on the spokes  101  and/or band  117  allows the projection of light which illuminates a subject in a manner that appears to be uniform. The configuration according to the invention has the advantage of not having light-generating or other elements held in the interior area of the fixture which may interfere with light projected from LEDs  103 . 
         [0075]      FIG. 3  shows an embodiment of the invention.  FIG. 3  shows a fixture  106  with spokes  101  connected to pivots which are mounted to or connected to a central hub  102 . When the distal ends  113  of the spokes  101  are released, the spokes  101  may pivot back so as to collapse in the form of an inside out umbrella. This can be done with the cover  107  fully or partially removed or with a cover provided with a slit to allow circumferential expansion/deformation of the distal ends. 
         [0076]    A slit in the cover  107  may be closed. The closure may be held in place by snaps, a zipper, a hook and loop element or other mechanism.  FIG. 4  shows an embodiment of a fixture  106  in a collapsed configuration suitable for storage. The fixture  106  may be stored in a soft or rigid container. The container may be a generally cylindrical container sufficiently sized to accommodate the hub and spokes. According to an embodiment, the backing may be used to wrap around the collapsed fixture&#39;s spokes and secure them for storage. 
         [0077]      FIGS. 7 and 8  show an enlarged view of an embodiment of a hub  102  according to the invention. Several articulation elements  201  are omitted or detached for illustration purposes. The central hub  102  may include a support structure  203 . 
         [0078]    Support structure  203  may be the base of the central hub  102 . The embodiment illustrated is suitable to carry spokes  101 . A central hub  102  may be configured with a greater or lesser number of spokes. The number of spokes is related to the stability of the structure and the light generation. A mounting element  112  may be provided on the external or back side of the support structure  203  of the central hub  102 . A mounting element  112  may be provided to facilitate attachment of the support structure  203  to a fixture mounting. Advantageously the mounting element may be connected to a tripod, boom, handle or a linkage to a holding device. Spoke assemblies  205  may be attached to support structure  203 . The spoke assemblies  205  may include spokes  101  attached to articulation elements  201 . For ease of illustration, spoke assemblies  205   a  and  205   b  are illustrated separately and not connected to support structure  203  in  FIGS. 7 and 8 . Each spoke assembly  205  is connected to the support structure  203  at a mounting station  204 . For ease of illustration, no spoke assembly is shown in  FIGS. 7 and 8  for mounting stations  204   a  and  204   b.  According to a preferred embodiment,  8 -spoke assemblies  205  will be mounted each at a corresponding mounting station  204 . 
         [0079]    Each mounting station  204  of the support structure  203  may have pin  206 . Each articulation element  201  may have a swivel bearing  207 . When assembled, the pin  206  extends through a bearing hole  213  defined by the swivel bearing  207 . For ease of assembly and fabrication, the swivel bearing may be a split bearing with a first portion carried by the limiting tab  210  and second portion mating with and fixed to the first portion of swivel bearing  207 . 
         [0080]    The support structure  203  may have a mounting recess  215 . The mounting recess  215  is sized to accommodate the pin  206  and the swivel bearing  207 . The pin  206  may be inserted through a pin insertion hole  208  into the bearing hole  213 , extend through the swivel bearing  207 . When assembled the ends of pin  206  may engage the support structure  203  at opposing sides of the mounting recess  215 . The articulation element  201  may pivot around the pin  206  at each mounting station  204 . The support structure  203  has an abutment surface  209  which may cooperate with the limiting tab  210  to limit the rotation of the articulation elements  201  of the spoke assemblies  205 . The articulation elements  205  may be configured with the rotational limiting tab  210  extending beyond the swivel bearing  207 . The articulation element  201  may pivot so that the rotational limiting tab  210  approaches the abutment surface  209 . When the limiting tab  210  engages with the abutment surface  209 , the rotation of the articulation element  201  may be limited. 
         [0081]    The limiting tab  210  may be composed of an outer clamping element  211  joined to an inner clamping element  212 . Advantageously the spoke  101  may be received and held in place between the outer clamping element  211  and the inner clamping element  212 . 
         [0082]    The mounting stations  204  may have a stabilizing recess  213 . The articulation elements  201  may have a stabilizing boss  214  which engages the stabilizing recess  213  when the articulation elements  201  are rotated to their limits. 
         [0083]    According to an advantageous feature of the invention, a controller may be connected to the LED bands in order to set the color, temperature and/or intensity of light generated by the LEDs. 
         [0084]    The invention is described in detail with respect to preferred embodiments, and it will now be apparent from the foregoing to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and the invention, therefore, as defined in the claims, is intended to cover all such changes and modifications that fall within the true spirit of the invention. 
         [0085]    Thus, specific apparatus for photographic lighting have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the disclosure. Moreover, in interpreting the disclosure, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced.