WO2013098678A1

WO2013098678A1 - Lightning device

Info

Publication number: WO2013098678A1
Application number: PCT/IB2012/056943
Authority: WO
Inventors: Fabrizio ZAMPETTI; Emanuele D'AMICO
Original assignee: Zampetti Fabrizio; D Amico Emanuele
Priority date: 2011-12-27
Filing date: 2012-12-04
Publication date: 2013-07-04
Also published as: ITRM20110688A1

Abstract

The present invention refers to a lighting device in the photography field, in particular for diffusion and conveyance of light produced by a lighting member. The invention allows the photographer to rely on different sizes of softbox without having to select in advance the equipment to be utilized, always bringing along a complete set of professional softboxes in a simple backpack.

Description

LIGHTING DEVICE

DESCRIPTION

Application Field

The present invention refers to a lighting device in the photography field, in particular for diffusion and conveyance of light produced by a lighting member.

In the field, these devices are known under the name of "softbox". Therefore, in the present description, by the term softbox it is meant a fitting suitable for a precise and uniform conveyance of light produced by a lighting member.

State of the Art

Most of the products currently marketed as softbox meet precise operation needs and are substantially made all in the same way and according to the same technical specifications.

For instance, all provide a support for the lighting member and oft-times it is possible to choose a specific support on the basis of the type and/or brand of the lighting member to be used.

To the support some structure rods are therefore connectible which serve to prop the entire softbox. The number and position of the structure rods connected thereto can vary depending on the form of the softbox.

The rods are in general metallic, whole and flexible, apt to connect a conveying cloth to the support, tensioning the cloth itself and thereby forming the final peripheral structure of the softbox.

The external conveying cloth has the purpose of forming the structure and therefore defining the size thereof. It has to meet the following needs: guarantee internally the maximum reflecting power and reduce to a minimum the dispersion of light to the outside of the structure.

Moreover, an external diffusing web is nearly always present. It is a tight-woven translucent web, fastened to the external cloth. Its function is that of "spreading" lights, making the emission of light by the lighting member softer and photographically more beautiful.

Finally, a further internal diffusing web can be present, fastened to the external cloth and placed at a variable distance between the external diffusing web and the support of the lighting member. Precise dimensions and distances enable to uniform the emission of light between the center and the edges of the softbox.

Drawbacks of the Prior Art

However, the products marketed to date entail at least one relevant drawback.

Softboxes are generally distinguishable into two macrocategories:

- Professional and semi-professional equipment, oft-times large sized, of remarkable weight and encumbrance. It is an equipment hardly used on-location, especially in case of photographic services without assistants, where therefore the photographer has to provide the installing of the lighting equipment. In this case, the encumbrance and weight of the equipment require to assess in advance which softboxes should be brought along.

- Amateur equipment, oft-times of small, when not of very small size. In most cases, it is equipment that, by seeking to emulate professional ones, imitates the latter's appearance without however providing a valid alternative, neither in qualitative terms nor in terms of dimensions.

With the progressive increase of on-location services and the decrease of budgets intended for photographic services, portability and lightness of weight have become ever more relevant.

Currently known devices are not particularly fit for this purpose, as they are always very heavy, not at all to minimally re-closeable, and therefore hardly portable.

Some examples of devices addressing these problems do exist, e.g. the one described in WO03071351 . This device is realized with a single structure consisting of flexible panels, foldable and collapsible into a smaller circular structure. Though possibly having a claim to a reasonable ease of assembly and disassembly, it entails the drawback of an excessive weight and an excessive encumbrance when in a closed configuration. Therefore, it is in fact marketed only to a maximum size of 90x90 cm.

Another typology of devices attempting to solve the same problem is that of devices having an umbrella-like structure, such as, e.g., described in CN2600839.

Also these devices are sufficiently easy to open and close, but have however an excessive weight and an excessive encumbrance, when in a closed configuration, with consequent transport problems.

The problem to be solved was therefore to succeed to combine sizes and qualities comparable to those of professional softboxes, concomitantly maintaining extremely reasonable weight and volume for improved ease of transport and simplicity of assembly.

Objects of the Invention

Object of the present invention is to solve the numerous problems still left open by the known art, and this is attained by a device as defined in claim 1 .

Further features of the present invention are defined in the corresponding dependent claims.

Advantages of the Invention

The present invention, by overcoming the mentioned problems of the known art, entails several evident advantages.

In particular, the invention allows the photographer to rely on different sizes of softbox without having to select in advance the equipment to be utilized, always bringing along a complete set of large-size softboxes in a simple backpack. However, in spite of the invention being contrived, above all, for on-location photographic services, having no specific differences with respect to a traditional studio softbox, it is deemed that even who mainly makes photographic services in a studio might prefer an equipment lighter in weight and less bulky once put away. In fact, one of the particularly advantageous aspects of the present invention lies precisely in the possibility of making the device assume an operating configuration and a resting configuration. In other words, it is a completely foldable and re-closeable device.

Transit from the resting configuration to the operating one, and vice versa, is particularly rapid, thanks to the shape of the rods of the device and to the typology of materials selected.

Moreover, the device entails a remarkable difference in terms of volume between the operating configuration and the resting one; therefore, when resting it actually takes up an extremely reduced space, though being able to assume decidedly high dimensions when it is operating.

Brief description of the drawings

The present invention, by overcoming the problems of the known art, entails other several evident advantages that, along with the features and the operation modes of the present invention, will be made apparent from the following detailed description of preferred embodiments thereof, given by way of example and not for limitative purposes. Reference will be made to the figures of the annexed drawings, wherein:

Figure 1 is a view of the structure of a partially assembled device according to the present invention, ;

- Figures 2A to 2C show one of the structure rods according to the present invention, and its folding mode;

Figure 3A is a rear perspective view of an assembled device according to the present invention;

Figures 3B, 3C are details of Figure 3A;

- Figure 3D shows a detail of an alternative embodiment;

Figures 4A and 4B refer to a particular shape of the rods according to an alternative embodiment of the present invention; Figure 5 is a front perspective view of an assembled device according to the present invention, ;

Figure 6A is a view of an internal diffusing web according to the present invention;

- Figure 6B is a front perspective view of a device according to the present invention, with the internal diffusing web partially assembled;

Figure 7A is a view of an external diffusing web according to the present invention; and

Figure 7B is a front perspective view of a device according to the present invention, with the external diffusing web partially mounted.

Detailed Description of the Drawings

The present invention will hereinafter be described in detail making reference to the above-indicated figures.

In particular, Figure 1 shows a support structure of a device 1 according to the present invention. The device 1 comprises first of all a support 2 for a lighting member 8. Then, the structure comprises some structure rods 3 apt to be made integral to the support 2. In the example described herein, the device provides four structure rods 3, arranged at the corners of a substantially pyramid-shaped volume having a quadrangular base. However, it is to be understood that the number and dimensions of the rods could vary depending on the shape and dimensions that are to be obtained for the device.

The structure rods are such that, in an operating configuration thereof, they are completely extended and prove to be flexible, so that they can tension a conveying cloth 10 for conveyance of light emitted from the lighting member 8.

According to the present invention, each one of the rods 3 can however assume two configurations, an operating one as described above, and a resting one. In the resting configuration, each rod is folded into two or more rod portions 4. Such configuration is illustrated in next Figures 2A to 2C.

In particular, the rods 3 are preferably made of aluminum. They are of substantially cylindrical section and tubular.

Advantageously, the portions 4 are connectible therebetween at ends thereof, so as to form overall a single extended rod 3. For this purpose, junction means or joint means of various type may be provided, from bayonet joints to hinges. A person skilled in the field could choose the preferred junction mode, depending on design needs.

According to a preferred embodiment, the rod portions 4 are internally connected therebetween by means of an elastic member 5 which, preferably, is passing through all rod portions 4 constituting a rod 3 and fastened at both ends of the terminal portions, i.e. of the rod itself.

Junction between the various portions occurs by means of telescopic joints 6, as shown in Figure 2C.

This makes the operation of extending and/or folding the rods and their storage in a resting configuration particularly simple .

Preferably, at one of the two ends, each rod has a reinforced region for bearing the great strains developed in the point of jointing with the support 2 of the lighting member 8. At the opposite end, as will be better described hereinafter, a pin 7 can be provided, apt to be inserted into a corresponding slot 15 made on the conveying cloth, as visible in Figures 3B and 3C.

In order to obtain a particularly light-weight product, yet concomitantly functional and meeting technical requirements in terms of light emitting efficiency, it is preferable that the material used for the manufacturing of the conveying cloth 10 be specifically selected. Moreover, always in an attempt at realizing a device particularly light-weight and scarcely bulky, the conveying cloth 10 is made of a single fabric and not through overlap of plural fabrics/materials coupled to each other.

In particular, according to the present invention, through countless tests performed on an enormous variety of materials the Inventors selected 190T polyester.

Preferably, a conveying cloth 10 of this material is therefore in a finish of a dark color, preferably black, in the portion 1 1 remaining outside the concavity when the device is in use, and in a reflective finish in the portion 13 remaining inside the concavity when the device is in use.

E.g., the reflective finish can be obtained by means of a silver varnish spread on the cloth.

Advantageously, as illustrated in Figure 3A, the device provides a member 12 for thickening the cloth at the support 2 for the lighting member 8. Said thickening member is, preferably, a grey-colored flat print apt to seal fabric pores near the lighting member, thereby isolating to a greater extent light that might come out of the softbox.

As already mentioned, the device comprises a plurality of rods 3, whose number depends on the final shape that is to be obtained. In particular, the conveying cloth 10 comprises a plurality of through slots 16 for housing the rods 3.

In order to make simpler the assembly of the rods on the cloth, it is preferable that the through slots be made on the external portion of the conveying cloth 10.

As shown in Figures 3B and 3C, the conveying cloth 10 at its vertexes comprises respective detent members 15, e.g. metallic slots. Each of such detent members is apt to cooperate with an end pin 7 of a respective rod 3, so that, in the operating configuration, the cloth be fully stretched.

Advantageously, at the vertexes of the conveying cloth 10 further eyelets 24 can be provided, close to the points of jointing of the rods on the cloth itself, as shown in Figure 3D. Such further eyelets 24 are contrived to enable a stabilization by anchoring of the device to the ground or to other existing structures, in order to oppose the effect of wind.

Referring now to next Figures 4A and 4B, according to an alternative embodiment, the rods 3 that, as already indicated, are preferably made of hollow aluminum, have a precurved region 25, for facilitating the insertion of the terminal end 7 in the detent slot

15 and/or the connection of the end of the rod with the support 2 of the lighting member. Moreover, such precurving 25 allows the rod to flex without breaking or damaging upon reaching its operating configuration. In fact, it should be noted that the strains that the rods have to bear are decidedly high.

At the support 2 of the lighting member, the conveying cloth 10 may have, advantageously, removable fastening members, e.g. of Velcro® type.

Such members allow a quick and simple fastening thereof and concomitantly prevent light from coming out from those zones about the lighting member that would inevitably remain uncovered.

Refer now to Figures 6A and 6B. To complete the device according to the present invention, an internal diffusing web 20, anchorable to the conveying cloth 10, may be provided.

In particular, the internal diffusing web 20 comprises a plurality of hooks 21 for anchoring to respective anchoring members 22 present on the conveying cloth 10, for instance at specific points of the internal corners.

Next Figures 7A and 7B refer instead to a further fitting.

In particular, according to the present invention, it is advantageously provided an external diffusing web 30, it also anchorable to the conveying cloth 10.

Having to be anchored along the entire periphery of the external edge of the conveying cloth 10, the external diffusing web may be equipped with a peripheral member 31 of Velcro^® for anchoring to a respective peripheral member 32 of Velcro^® present on an edge of said conveying cloth 10. Both the internal diffusing web 20 and the external diffusing web 30 are, according to the present invention and for what said above, made of 190T polyester and in particular of a translucent white coloring.

The device 1 made according to the present invention was compared with a known- type softbox, and various tests were performed to test the different aspects thereof.

Test on powers

With respect to a traditional Softbox, there was found a power drop equal to about one-third of stop to the disadvantage of the device according to the present invention:

Dispersion of light in the environment

The extreme lightness of weight of the conveying cloth causes in the device according to the present invention a greater dispersion of light in the environment with respect to a generic Softbox.

However at a delivered power of f 32, dispersion in the environment is equal to a value f1 .4, quantifiable in 9 stops; hence, well over a normal latitude of photographic exposure. Therefore, this aspect can be deemed irrelevant. Test on weights

The test was performed using a precision balance capable of a weighing sensitivity of tenths of grams.

Two devices of equal size (90x120 cm) were compared.

Measurements of every part of the devices were performed, reporting in percentage points the deviation between the various weights.

The greater saving of weight is attributable to the structure rods, for which the device according to the present invention can boast a -56%, and to the external conveying cloth of 190T polyester, for which the device according to the present invention can boast a -73%.

From this data, it is easy to imagine how with the increase of the device size the saving of overall weight may increase considerably, approaching -80%.

Test on volumes

From the tests, it is inferred that the device according to the present invention allows a relevant saving of volume, quantifiable in about a -62%.

Yet, the most interesting data is that related to the encumbrance of the disassembled device, and therefore the length of a bag for its transport. From about 95 cm of a standard bag, to 37cm (-61 .1 %). This deviation enables the device according to the present invention to be transported in a standard backpack.

Table of weiahts and measures

Shade of color

The test was performed by taking three photos of a 24 color-notch Chart. For each photo, the 24 color-notches were sampled and RGB values of each color were sampled. Subsequently, values were compared considering deviations in percentage points; from the test it is possible to understand what type of chromatic variation is obtained by utilizing a Softbox, and what type of difference exists between a generic Softbox and the innovative Softbox proposed herein.

The first photo was taken without Softbox use, naked-bulb; on this photo a white- point sampling was carried out, applied then to the other two photos. The values obtained from this photo represent reference data for understanding chromatic variations of the other two photos. Diaphragm values: f16.

The second photo was taken with the device according to the present invention, marked in the Table by the abbreviation "Softbox LGHT"

The third photo was taken with a generic Softbox, marked in the Table by the abbreviation "Softbox PRL".

In the last column ("DIFF") differences in chromatic yield between the two Softboxes are reported in percentage points.

A >2% deviation was only rarely detected.

0% deviation = 29% of notches measured

1 % deviation = 29% of notches measured 78.83%

2% deviation = 20.83% of notches measured

3% deviation = 16.6% of notches measured 20.76%

4% deviation = 4.16% of notches measured Shade of color Table

The present invention has been hereto described with reference to a preferred embodiment thereof. It is understood that other embodiments might exist, all falling within the concept of the same invention, and all comprised within the protective scope of the claims hereinafter.

Claims

1. A device (1 ) for lighting, suitable for diffusion and conveyance of light, comprising:

- a support (2) for a lighting member;

- a single conveying cloth (10) for conveyance of light emitted from said lighting member;

- a support structure (3) for supporting said conveying cloth, apt to be made integral to said support (2),

characterized in that said structure comprises a plurality of rods (3), each rod (3) being able to assume a first operating configuration, fully extended, and a resting configuration folded into two or more rod portions (4), said rod being flexible in the operating configuration, said two or more portions being connected therebetween by means of an elastic member (5),

wherein said conveying cloth (10) assumes a substantially concave shape when the device is operating and has a reflective finish on a side (13) internal to its concavity obtained by a silver varnish spread on the cloth (10),

said device (1 ) further comprising a member (12) for thickening the conveying cloth (10) at the support (2) for the lighting member (8), apt to seal the pores of the conveying cloth (10) near the lighting member (8).

2. The device according to claim 1 , wherein said conveying cloth (10) is made of 190T polyester.

3. The device according to one of the preceding claims, wherein said conveying cloth (10) comprises a plurality of through slots (16) for housing said rods (3).

4. The device according to claim 3, wherein said through slots (16) are made in the external portion of the conveying cloth (10).

5. The device (1 ) according to one of the preceding claims, wherein said rods have a precurved region (25).

6. The device (1 ) according to one of the preceding claims, wherein said conveying cloth (10) comprises a plurality of detent members (15), each one apt to cooperate with an end pin (7) of a respective rod (3), so that, in the operating configuration, the cloth (10) be fully stretched.

7. The device (1 ) according to one of the preceding claims, wherein said conveying cloth (10) comprises a plurality of eyelets, suitable for a stabilization by anchoring of the device.

8. The device according to one of the preceding claims, wherein the conveying cloth (10) has removable fastening members (14), e.g. of Velcro® type.

9. The device (1 ) according to one of the preceding claims, further comprising an internal diffusing web (20), anchorable to the conveying cloth (10).

10. The device according to claim 9, wherein said internal diffusing web (20) comprises a plurality of hooks (21 ) for anchoring to respective anchoring members (22) present on said conveying cloth (10).

11. The device according to one of the preceding claims, further comprising an external diffusing web (30), anchorable to the conveying cloth (10).

12. The device according to claim 1 1 , wherein said external diffusing web (30) comprises a peripheral member (31 ) of Velcro^® for anchoring to a respective peripheral member (32) of Velcro^® present on an edge of said conveying cloth (10).

13. The device according to claim 1 1 or 12, wherein said internal diffusing web (20) e/o said external diffusing web (30) is made of translucent white 190T Polyester.

14. The device according to one of the preceding claims, wherein said elastic member (5) is passing through all rod portions (4) constituting a rod (3) and fastened to both ends of the rod itself.