A custom gobo is actually a stencil or template placed inside or in front of a light source to control the shape of the emitted light. Lighting designers typically make use of them with stage lighting instruments to manage the shape of the light cast over a space or object-for example to generate a pattern of leaves on a stage floor. Sources
The word “gobo” has come to sometimes reference any device that creates patterns of light and shadow, as well as other items that go before a mild (such as a gobo arm or gobo head). In theatrical lighting, however, the term specifically identifies a system positioned in ‘the gate’ or in the ‘point of focus’ in between the light source and also the lenses (or other optics). This placement is important as it generates a crisp, sharp edged pattern or design (of logos, fine detail, architecture, etc.). Gobos placed after the optics tend not to create a finely focused image, and therefore are more precisely called “flags” or “cucoloris” (“cookies”).
he exact derivation of gobo is unclear. It is cited by some lighting professionals as “goes before optics” or, more infrequently, “goes between optics”. An alternate explanation is “graphical optical black out.” The word is traced returning to the 1930s, and originated in reference to a screen or sheet of sound-absorbent material for shielding a microphone from sounds provided by a specific direction, without any application to optics. The treating of the word as being an acronym is recent and ignores the original definition in support of popular invention. There are numerous online examples of acoustic gobos. The word more than likely is actually a derivative of “goes between.”
A led gobo projector in the Earth, projected utilizing a halogen projector. Gobos are used with projectors and simpler light sources to produce lighting scenes in theatrical applications. Simple gobos, included in automated lighting systems, are popular at nightclubs as well as other musical venues to produce moving shapes.Gobos could also be used for architectural lighting, along with interior design, as in projecting a company logo on the wall.
Gobos are created from various materials. Common types include steel, glass, and plastic. Steel gobos or metal gobos utilize a metal template from which the picture is reduce. They are the most sturdy, but often require modifications for the original design-called bridging-to present correctly. To correctly represent the letter “O” for instance, requires small tabs or bridges to aid the opaque center from the letter. These could be visible within the projected image, which might be undesirable in some applications.
Glass gobos are made of clear glass with a partial mirror coating to bar the lighting and provide “black” areas in the projected image. This eliminates any need for bridging and accommodates more intricate images. Glass gobos could also include colored areas (just like stained glass windows), whether by multiple layers of dichroic glass (one for every color) glued on an aluminium or chrome coated white and black gobo, or by newer technologies that vary the thickness in the dichroic coating (and therefore the colour) in a controlled way on a single piece of glass-which makes it possible to turn a color photo right into a glass gobo. Glass gobos generally offer the highest image fidelity, but they are the most fragile. Glass gobos are generally designed with laser ablation or photo etching.
Plastic gobos or Transparency gobos can be used in LED ellipsoidal spotlights. These “LED Only” plastic gobos can be full color (such as a glass gobo), however are much less delicate. These are a new comer to the current market, as well as LED lights, along with their durability and effectiveness vary between brands.
Before, plastic gobos were generally custom made for when a pattern requires color and glass will not suffice. However, in a “traditional” (tungston-halogen) light fixture, the main objective point position of any gobo is very hot, so these thin plastic films require special cooling elements to avoid melting. A lapse inside the cooling apparatus, even for seconds, can ruin a plastic a gobo in a tungsten-halogen lighting instrument.
Patterns – Theatrical and photographic supply companies manufacture many basic and complex stock patterns. They also can produce custom gobos from customer artwork. Generally, a lighting designer chooses a pattern from the manufacturer’s catalog. Because of the multitude of gobos available, they are often described by number, not name. Lighting technicians can also hand cut custom gobos from sheet metal stock, as well as aluminum pie tins.
Gobos are often found in weddings and corporate events. They could project company logos, the couple’s names, or just about any artwork. Some companies can change glass gobo in as little as per week. Designers rxziif use “stock” gobo patterns for such events-as an example for projecting stars or leaves to the ceiling.
The term “gobo” is also employed to describe black panels of various sizes or shapes placed between a source of light and photographic subject (such as between sun light and a portrait model) to control the modeling effect of the existing light. This is the complete opposite of a photographer utilizing a “reflector” to redirect light into a shadow, which is “additive” lighting and most frequently used. Utilization of a gobo subtracts light from a part of an overall shaded subject and produces a contrast between one side from the face and the other. It allows the photographer to show with wider open apertures giving soft natural transitions in between the sharp subject and unsharp background, called bokeh.