GB2386943A

GB2386943A - Photographic light diffusion apparatus

Info

Publication number: GB2386943A
Application number: GB0303531A
Authority: GB
Inventors: Gary James Astill
Original assignee: Lastolite Ltd
Current assignee: Vitec Imaging Solutions UK Ltd
Priority date: 2002-02-25
Filing date: 2003-02-17
Publication date: 2003-10-01
Also published as: GB0204290D0; WO2003071351A1; GB0303531D0; AU2003209980A1

Abstract

Photographic light diffusion apparatus (softbox) comprises three or more panels (1,2,3,4) connected at major edges thereof so as to form a generally pyramidal enclosure having an apex (5) that is adapted to be mounted on a photographic lamp, and a base that is adapted to receive a light-modifying screen. Each panel (1,2,3,4) comprises a sheet of flexible material that is supported in tension by a flexible resilient hoop. The enclosure can therefore be very rapidly and easily collapsed and re-erected.

Description

1 2386943

Title- Photographic lighting apparatus This invention relates to lighting apparatus for use in photography, and in particular to a light diffusion box of the type commonly known as a "softbox".

Light diffusion boxes or softboxes are commonly used in photography to modify the light used to illuminate the photographic subject. Such a softbox typically comprises a generally pyramidal, tensioned fabric enclosure that is mounted on a lamp. The sides of the enclosure are usually opaque, while the base is 10 translucent, typically being covered by a fabric sheet through which light from the lamp passes. The effect of the fabric sheet is to "soften" the light falling on the subject. Softboxes of the type described are most commonly used in location shooting.

15 However, because they are relatively bulky items (the base of the enclosure commonly being up to 1 metro square), they are usually transported in a collapsed condition and are erected immediately prior to use. To achieve this, the softbox normally comprises a framework over which the fabric enclosure is stretched. Unfortunately, known designs of sofibox are rather cumbersome and difficult to erect. In addition, although the framework can be disassembled for storage and transport, the length of some of the components may be quite considerable (eg 1 metre or more) which makes it inconvenient for them to be carried by a 25 photographer travailing on foot. The time taken for the softbox to be erected and disassembled repeatedly, as may be required by, for example, a television news team working on location, may also be excessive.

There has now been devised an improved form of photographic lighting 30 apparatus, of the type known as a softbox, which overcomes or substantially

mitigates the above-mentioned and/or other disadvantages associated with the prior art.

According to the invention, there is provided photographic lighting apparatus 5 comprising three or more panels connected at major edges thereof so as to form a generally pyramidal enclosure adapted at the apex thereof to be mounted on a photographic lamp, the base of the pyramidal enclosure being adapted to receive a light-modifying screen, wherein each panel comprises a sheet of flexible material that is supported in tension by a flexible resilient hoop.

The lighting apparatus according to the invention is advantageous primarily in that the enclosure can be very rapidly and easily collapsed and re-erected. In order to collapse the enclosure, it is removed from the lamp and folded so that the panels overlie one another. By relative twisting of opposite sides of the 15 panels and folding, the enclosure can be reduced to a much smaller effective size and stowed in a compartment or bag provided for the purpose. By way of example, an enclosure having a base approximately 1 metre square may be reduced in size to a package approximately 30cm in diameter.

20 The apparatus may comprise panels of any shape suitable for forming a generally pyramidal enclosure. For instance, the panels may be generally trapezoidal or triangular in shape but preferably with rounded corners. The panels are preferably all of the same shape and dimensions.

25 It is particularly preferred that the panels should not be connected directly together7 but should be connected by a flexible gusset interposed between adjacent edges of the panels. The provision of such gussets facilitates folding of the panels when it is desired to collapse the apparatus for storage or transportation.

The panels of the apparatus are preferably arranged and connected in such a way that the apparatus is foldable into an arrangement where the panels overlie one another, thereby forming a stack of panels. In this case, the gussets must therefore be of sufficient width for this arrangement to be possible. From such an 5 arrangement, it is preferably possible to twist and then fold the stack of panels so that each flexible hoop becomes doubled over and generally circular in form, thereby reducing the size of the apparatus considerably for storage or transportation. 10 The panels may be arranged in a chain, with each panel being able to fold relative to its adjacent panel into an arrangement where these adjacent panels overlie one another. In this way, such a chain of panels may be folded to form a stack of panels. In this case, the apparatus preferably includes means for securing the two ends of the chain together when the apparatus is erected.

However, most preferably, the apparatus comprises an even number of panels which are connected together so that, when erect, the panels form a generally pyramidal enclosure. Most preferably, the apparatus is arranged so that the panels can be pushed together so that the apparatus folds along two lines into an 20 arrangement where each panel overlies another panel. Each pair of overlying panels is then preferably able to fold relative to its adjacent pair of panels into an arrangement where these adjacent pairs of panels overlie one another. In this way, the pairs of panels may be folded in turn to form a stack of panels.

25 Most preferably, the apparatus according to the invention comprises four panels which together form a four-sided pyramidal enclosure with a square base and an opening at the apex by which the enclosure can be mounted on a lamp or the like. 30 The panels are most preferably formed of a fabric, most preferably a woven synthetic fabric. The fabric is preferably substantially inelastic.

Most preferably, the fabric of each panel is provided with a peripheral tube within which a resilient hoop is accommodated, the hoop serving to tension the fabric of the panel in a shape that is determined by the shape of the fabric.

The resilient hoop is most preferably formed of a band of resilient material, eg a flat strip of resilient material. The band is most preferably formed in a metal such as steel. The band preferably has a width of between 5mm and 1 5mm, and where the band is formed in metal, preferably has a thickness of between 0.5 and 1 0 2mm.

The apparatus preferably includes an opening at the apex of the generally pyramidal enclosure. The periphery of such an opening is preferably defined by the ends of the panels remote from the base of the enclosure.

The enclosure is most preferably mounted, in use, on a photographic lamp by means of an adapter hub which has peripheral formations by which the enclosure may be engaged with the hub. Most preferably, such formations take the form of recesses within which the resilient hoops engage, the enclosure being 20 maintained in engagement with the hub by the resilience of the hoops. The hub is preferably circular and the peripheral formations are preferably a peripheral groove that permits rotation of the enclosure relative to the hub.

The invention will now be described in greater detail, by way of illustration only, 25 with reference to the accompanying drawings, in which Figure 1 is a perspective view of a softbox enclosure according to the invention; Figure 2 is a plan view of a mounting hub by which the enclosure of Figure 1 is 30 mounted on a photographic lamp;

Figure 3 is a cross-sectional view on the line lll-lil in Figure 2; Figure 4 is a detailed view on the arrow IV in Figure 1; and 5 Figure 5 shows stages in the collapse of the enclosure of Figure 1 for storage.

Referring first to Figure 1, a softbox enclosure comprises four generally triangular or trapezoidal panels 1,2,3,4, which are connected at their sides so as to form a generally pyramidal enclosure with an opening 5 at the apex.

Each panel 1,2,3,4 comprises a sheet of substantially inelastic fabric, most preferably a woven synthetic fabric, eg of nylon. A fabric tube 9 is stitched to the periphery of the sheet and contains a continuous, resilient hoop. The hoop is typically formed from a band of carbon spring steel, most preferably having a 15 width of about 10mm and the ends of which are riveted together to form the hoop.

The effect of the hoop is to maintain the sheet of fabric in tension, the shape of the tensioned panel being determined by the shape of the sheet of fabric The sheets of fabric are opaque and the surfaces of each sheet that are on the 20 interior of the enclosure have a reflective surface.

Adjacent panels 1,2,3,4 are connected by narrow gussets 6 (visible in Figure 4) of approximate width 2cm and of similar material to the material of the sheets of fabric. These gussets assist in folding of the enclosure for storage as described 25 below.

Referring now to Figures 2 and 3, a mounting hub is generally designated 10.

The hub 10 is circular and takes the form of a shallow bowl with a central opening to which is fitted a standard adaptor 11 by which the hub 10 can be mounted on a 30 photographic lamp. The rim of the hub 10 is formed with a peripheral groove 12.

The enclosure is mounted on the hub 10. after the hub 10 has been fitted to the lamp, simply by fitting the opening 5 over the rim of the hub 10 until the parts of each hoop located at the periphery of the opening 5 locate in the groove 12.

When the enclosure is so engaged with the hub 10, the enclosure may easily be 5 rotated around the hoop 10.

As can be seen in Figure 4, the terminal portion of the gusset 6 is formed of an elasticated material 7 that stretches to occlude the space between the parts of two hoops that diverge in the vicinity of the opening 5. This minimises spaces 10 between the enclosure and the hub 10 and hence minimises rearward escape of light from the enclosure.

Strips 8 of touch-and-close material (VELCRO-type) material are fastened to the internal surfaces of each panel 1,2,3,4. These strips 8 are spaced upwardly 15 from, and disposed parallel to, the basal edges of each panel 1,2,3,4. A light-

modifying screen (not shown in the drawings) comprising a square of translucent fabric having the desired light-modifying properties is, in use, fitted to the enclosure by engagement with the strips 8 of mating touch-and-close material provided at the edges of the screen. In some applications, no such screen may 20 be used, the enclosure then being employed simply to direct and concentrate light from the lamp onto the subject.

Further strips 7 of touch-and-close material are provided on the external surfaces of each panel 1,2,3,4 to enable a further screen (again not shown in the 25 drawings) to be fitted to the enclosure, this screen being of greater dimension than the base of the enclosure and again having corresponding touch-and-close material by which it can be engaged with the further strips 7.

When it is desired to collapse the softbox, the enclosure is simply pulled away 30 from the hub 10 and the light-modifying screen (if any) removed by disengagement of the touch-and-close fastenings. The enclosure is collapsed

and folded (Figures 5a and 5b) until the four panels 1,2,3,4 lie on top of each other (Figure 5c). The presence of the gussets 6 between the panels 1,2,3,4 facilitates the folding operation. The folded panels are reduced further in size by grasping opposite sides and twisting to form loops which can then be folded over 5 (Figures 5d and 5e). The folded enclosure can then be stowed in a pouch or other receptacle until it is next required. The shape and dimensions of the collapsed enclosure are such that the hub 10 may also be stored with it

Claims

1. Photographic lighting apparatus comprising three or more panels connected at major edges thereof so as to form a generally pyramidal enclosure 5 adapted at the apex thereof to be mounted on a photographic lamp, the base of the pyramidal enclosure being adapted to receive a light-modifying screen, wherein each panel comprises a sheet of flexible material that is supported in tension by a flexible resilient hoop.

10

2. Photographic lighting apparatus as claimed in Claim 1, wherein the panels are generally trapezoidal or triangular in shape.

3. Photographic lighting apparatus as claimed in Claim 1 or Claim 2, wherein the panels have rounded corners.

4. Photographic lighting apparatus as claimed in any preceding claim, wherein adjacent panels are connected by a flexible gusset interposed between adjacent edges of the panels.

20

5. Photographic lighting apparatus as claimed in any preceding claim, wherein the panels are arranged and connected in such a way that the apparatus is foldable into an arrangement where the panels overlie one another, thereby forming a stack of panels.

25

6. Photographic lighting apparatus as claimed in Claim 5, wherein the panels are arranged in a chain, with each panel being able to fold relative to its adjacent panel into an arrangement where these adjacent panels overlie one another, thereby enabling a stack of panels to be formed.

7. Photographic lighting apparatus as claimed in Claim 6, wherein the apparatus includes means for securing the two ends of the chain together when the apparatus is erected.

5

8. Photographic lighting apparatus as claimed in Claim 5, wherein the apparatus comprises an even number of panels which are connected together so that, when erect, the panels form a generally pyramidal enclosure.

9. Photographic lighting apparatus as claimed in Claim 8, wherein the 10 apparatus is arranged so that the panels can be pushed together so that the apparatus folds along two lines into an arrangement where each panel overlies another panel, and each pair of overlying panels is then able to fold relative to its adjacent pair of panels into an arrangement where these adjacent pairs of panels overlie one another, thereby forming a stack of panels.

10. Photographic lighting apparatus as claimed in any one of Claims 5 to 9, wherein the apparatus is adapted such that the stack of panels can be twisted and then folded so that each flexible hoop becomes doubled over and generally circular in form.

11. Photographic lighting apparatus as claimed in any preceding claim, wherein the apparatus comprises four panels which together form a foursided pyramidal enclosure with a square base and an opening at the apex by which the enclosure can be mounted on a lamp or the like.

12. Photographic lighting apparatus as claimed in any preceding claim, wherein the panels are formed of a fabric.

13. Photographic lighting apparatus as claimed in Claim 12, wherein the fabric 30 is substantially inelastic.

: 7

14. Photographic lighting apparatus as claimed in Claim 12 or Claim 13, wherein the fabric of each panel is provided with a peripheral tube within which the resilient hoop is accommodated, the hoop serving to tension the fabric of the panel in a shape that is determined by the shape of the fabric.

15. Photographic lighting apparatus as claimed in any preceding claim, wherein the resilient hoop is formed of a band of resilient material.

16. Photographic lighting apparatus as claimed in Claim 15, wherein the band 10 is formed in a metal.

17. Photographic lighting apparatus as claimed in any preceding claim, wherein the apparatus includes an opening at the apex of the generally pyramidal enclosure.

18. Photographic lighting apparatus as claimed in any preceding claim, wherein the enclosure is mounted, in use, on a photographic lamp by means of an adapter hub which has peripheral formations by which the enclosure may be engaged with the hub

19. Photographic lighting apparatus as claimed in Claim 18, wherein the formations take the form of recesses within which the resilient hoops engage, the enclosure being maintained in engagement with the hub by the resilience of the hoops.

20. Photographic lighting apparatus as claimed in Claim 19, wherein the hub is circular and the peripheral formations are a peripheral groove that permits rotation of the enclosure relative to the hub.

30

21. Photographic lighting apparatus substantially as hereinbefore described and as illustrated in the accompanying Figures.