When we talked about lighting and lighting design we usually mean indoor, outdoor or architectural lighting. What about the stage lighting? Stage Lighting is usually the hidden part of lighting market. However, Stage Lighting is full of fun it needs well background and technical qualification. So, I am totally focused on searching for the Stage Lighting Fundamentals on web and guess what I found? There are a few of websites serve in this field. Due that, I started to plan about writing Stage Lighting Fundamentals in basic level. Hope the post will guide you well!
The method for selecting equipment is best started by completing a lighting design. Equipment can then be selected to fulfill this design. To design the lighting, several physical aspects of the equipment must be known along with the basic theories of stage lighting.
GENERAL LIGHTING THEORY
Indoor theatrical lighting is designed in a manner to emulate the natural highlights and shadows that are created by the sun, or similarly, the reflection of the sun by the moon. Without these shadows and highlights, the human eye will sense an incongruity, attempt to correct it in the mind and eventually tire and lose interest in viewing the object. Once this occurs the eye will move on to other objects to be refreshed, eventually this will allow audio contact to be broken as well. Proper highlights and shadows, at proper light levels, maintains longer eye and audio contact keeping the audiences attention focused on the event. This is important for plays, church services and even speakers from a podium. Below are several of the main components to implement this theory.
The Sun: The sun strikes the northern hemisphere at a relative 45 degree angle; this angle produces specific highlights and shadows that are considered normal through the constant viewing of this arrangement. The extreme intensity of the sun creates a strong highlight on one side of a three-dimensional surface and strong shadows on the remaining areas. In a theatrical design, this would be the “key” light. Since the sun is so intense, it also generates a great deal of reflected (or bounce) light off of the surrounding surfaces. This reflected light fills in the shadows on the remaining sides of the object; in a theatrical design, it would be called the “fill” light. The intensity of this fill light is less than the intensity of the key light. The sun produces a white light that, when reflected off a surface, picks up the coloration of that surface. This bounce light fills the shadows with this colored light. This becomes the basic justification of the colored lighting in Theatre. It would be easy to simulate the sun and shadows indoors if we had a lighting fixture that could produce the same intensity as the sun. Unfortunately, this fixture is not available and we must use multiple fixtures to simulate the same effect.
The Moon: The moon provides a similar source and angle of light, but there are some significant differences, as we know, between sunlight and moonlight. Because moonlight is reflected sunlight, it is less intense and does not create the same bounce or fill effect. Nighttime lighting has much more contrast, or shadows, than daytime lighting.
THEATRICAL LIGHTING THEORY – STRAIGHT ON VIEWING
To duplicate the sun’s highlight and associated bounce light indoors, we must provide three lighting instruments as a minimum: one fixture to create the highlight (the key light) and two to create the associated fill light. The three fixtures can adequately illuminate a three-dimensional object on all sides. Though positions can vary, a basic design would include one fixture placed at a 45-degree angle above and 45 degrees to one side. This would be the key light. The second fixture at the same 45-degree angle above and to the side. A third light would be placed directly above or at a sharp angle to the rear, and this would also be a fill light (depending on its position, this is also known as a “downlight” or “backlight”). These three fixtures produce illumination that will be perceived to be similar to that of natural sunlight. The 45-degree angle is not unchangeable but keep in mind that extreme angles create extreme effects. A flat angle will create a generally shadowless light on the object, which is hard to control and tends to flatten the features of a person or object and creates a generally uninteresting kind of light. Conversely, an extremely sharp low angle of light from above or below will create exaggerated shadows on the face, which the eye is not accustomed to seeing. For example, a monster effect can be created by lighting a face from below, causing reversed shadows and an unnatural look.
The lighting for a night scene uses the same set up and the same fixtures. The moon creates a similar angle of light; however, the lighting should be less intense. To provide more options and colors to your lighting setup, more fixtures are hung using the same principle. First try adding additional back or down lights to increase the fill from the back, then add fronts for more key and fill possibilities.
THEATRICAL LIGHTING THEORY – MULTIPLE VIEWING ANGLES
The above theory is a basic design for one direction of viewing. If there is seating on three sides of a platform, the theory remains the same but the minimum layout changes. Using only two fixtures from the front would provide the viewer sitting on the side either all key light or all fill light, thus defeating the modeling effect you are trying to create. It is necessary to maintain the key and fill relationship for all viewing angles to create the shadows and highlights needed to model the object. A four-light front lighting scheme with two “keys” and two “fills,” provides this necessary relationship for ¾ round seating. The fill lights from the back remain the same.
One cost-effective option to the four-light system is the three-light system. Similar in theory to using four lights, three lights are positioned so that each viewing angle sees a key and a fill light. Two key lights from the sides and a fill light from the front will allow the fill light to perform double duty and provide each viewing angle with a key. Additional viewing angles would require additional fixtures using the same method.
THEATRICAL LIGHTING THEORY – EXPANDED
Other positions can be used to enhance lighting effects while still maintaining the theory-dictated parameters. Since bounce light radiates 360 degrees from the source, fixtures that act as fill lights can be hung in any position. In addition, the sun does not rise or set at a relative 45-degree angle. Extreme angles change the direction of the fill light. Fixtures hung from a side angle can be used to emulate the sun’s rising or setting. This side angle provides additional modeling of an object or body. It is heavily used in dance lighting to provide the audience with the best possible view in order to define the shape of the body.
Once the angles are chosen for illumination, color selection should be the next design element concentrated on. Humans, either from nature or artificial lighting, have been conditioned to associate certain colors of light with certain times of the day. Most people think of a middle-blue to dark-blue color as night because the eye has difficulty in discerning color in low levels of light. Also, the sun is considered yellow or light amber, though it is really white light. Red is associated with fire, although fire can include the full spectrum of light. These ingrained color responses allow the theatrical designer to properly light indoors and simulate outdoor lighting moods. Theatre fixtures are manufactured with a holder that accepts thin sheets of plastic color media called gel. Although gels are available in hundreds of shades, the selection of colors is very difficult to write about or teach. Fortunately, the sheets of gel are relatively inexpensive and trial and error can be the best method for finding the best color for your purposes. If your lighting instruments are attached to dimmers, you can change the colors of a single gel simply by increasing or decreasing the intensity of the lamp. The light from a lavender gel will become increasingly red as its lamp intensity is reduced. A limited selection of fixtures and colors does not necessarily mean a limited color palette. With practice you can learn how colors react to different intensities and how they react when used together. The selection of the basic key and fill colors again should emulate the sun or moon. The key color should be warm like sunlight and the fill should symbolize a reflection from the earth’s surfaces which are typically cool (gray concrete, brown wood, green leaves, etc). A good rule of thumb for basic lighting set ups is to choose a warm color and a cool color with similar color intensities. A brilliant yellow light would seldom produce a dark blue reflection; however, a deep lavender key could produce one. When using multiple key and fill angles it is possible to select gel colors which act as both a warm and cool light. For example when using three angles of front light, a rose tint could be used from the right, light lavender in the ones from the center and a medium blue in the ones from the left. The lavender would look cool when used with the rose yet warm when used with blue. Potentially, the medium blue run at full intensity could become the warm against a very low-intensity lavender. During a production with many scenes the entire color look of the light could be altered from scene to scene while still maintaining the basic lighting theory. Gel colors must also be selected with scenery and costumes in mind. White light is a combination of the primary (red, blue and green) and secondary (magenta, cyan and yellow) colors of light. These colors (wavelengths) are necessary for viewing pigment colors. Pigment is what provides color in objects. So, a blue fabric has blue pigment and will only appear blue if part of the light that strikes it contains a blue wavelength. Since white light has all the colors of the spectrum, all pigments look natural in it. If the light hitting the blue fabric only contained a red wavelength, the fabric would look like an off color shade red (depending on the fabrics makeup of primary and secondary pigments). True red, being a primary color, contains none of the blue wavelength. Similarly, the fabric would appear green if only a primary green light was shone on it; warm blue if magenta was shone on it and cool blue if cyan was shone on it (magenta and cyan being secondary colors that contain blue). The shades of blue will appear different since we based our “natural” blue color on observance under white light; remove one part of the light spectrum and any pigment will look different. For most beginners, the wrong selection of color can become a great calamity. The scenery, costumes and makeup can appear completely foreign to the designers and directors because they have most likely been viewing it all under relatively white incandescent light or slightly green florescent light. However, you can use color to your advantage with practice. A play’s dramatic turn from depressing to happy could be made even more dramatic if the lighting transforms the entire set from cool to warm. If the scenery was predominantly blue this could be done by changing the lighting from a cool blue-green light that suppresses the blue fabric color, to a blue or violet light allows (or enhances) the warm natural color of the fabric to be viewed.
The basic lighting theory is applied using standard theatrical equipment. This equipment also dictates the physical layout of the three-fixture theory. What follows is a description of lighting fixtures, their layout and an overview of the equipment used to power and control the fixtures.
DETERMINING LIGHTING AREAS AND FIXTURE NEEDS
To accommodate our lighting design, the area to be lit must be broken down into smaller units called focus areas. It is easiest to create 8-foot to 10-foot squares. The overlap from our fixtures, which must be selected to produce a 14-foot circle, allows overlap for even illumination from square to square. If we had an area of 20 feet by 20 feet to light (producing 4 areas) using the basic design discussed before, we would need a minimum of 8 fixtures in front and 4 fixtures above or in back. This would provide a basic well-lit platform area for viewing from the front. If the platform is to be viewed from three sides, the amount of fixtures needs to be modified by adding either one or two front lights per area for a minimum of 12 fixtures and still 4 fixtures from behind. The same lighting method is used to light special areas such as a single person or piano. In this case, the focus area may be smaller in order to cover only the specified object and may affect the fixture selected. These fixtures are normally referred to as “specials.”
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