What is the difference between TV light and stage lighting?

II. Characteristics of Television and Stage Lighting

2.1 Requirements for Lighting Intensity

The human eye can adapt to a wide range of brightness levels, from direct sunlight to the dim light of moonshine, allowing us to recognize objects and details. This ability is thanks to the automatic adjustment of the pupil.

Cameras, on the other hand, rely on aperture settings and sensor sensitivity to cope with various lighting conditions. Under low illumination, cameras can open up the aperture, while under high illumination, they close it down. However, the size of the aperture directly affects image quality, such as depth of field and clarity. An aperture that is too wide may cause flare, whereas one that is too narrow could lead to reduced image sharpness.

Therefore, as a TV lighting designer, maintaining an appropriate level of illumination is crucial to ensure that the camera can choose the most suitable aperture setting for capturing high-quality images.

Unlike stage lighting, TV lighting must take into account the camera's limitations in handling contrast. While stage lighting creates high contrast to pursue visual impact, television needs to control the ratio of light to avoid overexposure or excessive darkness in the picture. The management of light ratios physically exists objectively and cannot be altered by camera adjustments.

2.3 Display Index Requirements

The Television Lighting Consistency Index (TLCI) and Color Rendering Index (CRI) are important metrics for measuring the quality of light sources. Although LED light sources with high CRI are favored in film and television shooting, sources with high CRI do not always match the color reproduction of cameras, leading to color deviations during post-production color grading. The TLCI takes into account the color discrimination capabilities of cameras and has become the new standard for assessing the color performance of studio lights.

2.4 Use of Color

Stage lighting can depict nature and enhance emotions through bold and free use of color changes. Television lighting, however, is more conservative in its application of color because the colors captured by cameras tend to deepen on television screens. Therefore, when designing for TV lighting, one must consider the characteristics of cameras to ensure a comfortable presentation of colors on TV.

2.5 Consideration of Color Temperature

Color temperature affects the color rendering of light sources, measured in Kelvin (K). Under different color temperatures, the color appearance of objects can vary. Although the human eye is not very sensitive to these differences, cameras can precisely capture them.

In TV filming, consistency in color temperature is crucial. Any deviation in color temperature can lead to color discordance on the television screen. For instance, the color temperature of follow spot lights should match that of the studio's base light sources to prevent inaccurate reproduction of skin tones.

In summary, TV lighting design must not only satisfy the visual comfort of the audience but also align with the technical parameters of cameras to ensure the accurate transmission of color, brightness, and contrast on the television screen.

III. Several Differences in the Application of Television Lighting and Stage Lighting

The following content is summarized based on personal practice and reveals some differences between television lighting and stage lighting.

3.1 Treatment of "Black Zones" in Television Lighting

In stage lighting, there is usually no concept of "black zones," as long as the lighting coordinates with the stage effects to ensure visual comfort for the audience. However, in television lighting, if the camera captures a large area of darkness in the frame, this phenomenon is commonly referred to as a "black zone." If too many black zones appear in the shot, it can make the image seem heavy and hollow, which directors typically avoid. Sometimes, due to limitations, such shots must be used, and lighting plays a crucial role. For example, if there are scenic pieces, the frame can be enriched by lighting or projecting patterns; if there are no scenic pieces, beams of light can break the oppressive feeling and fill the void.

Therefore, whether it's television lighting design or stage design, advance communication with the director and cinematographer is crucial. The lighting designer needs to understand the camera angles and composition to achieve a perfect presentation of the frame.

3.2 Differences in the Use of Laser Lights

Laser lights are favored by lighting designers for their bright colors, high brightness, good directionality, long range, and ease of control. However, due to their concentrated energy, direct illumination on camera or film camera lenses can damage the photosensitive elements, so TV broadcast trucks are cautious about using laser lights. When using laser lights in TV production, it is essential to avoid directing them at the camera, which lighting designers should pay special attention to. When using laser lights, the designer should know the position of the camera in advance.

In stage lighting, as long as the eyes of the audience are not directly illuminated and it fits the demands of the plot, the use of laser lights can be more liberal.

3.3 Standards for the Exposure of Lighting Fixtures

Regarding the exposure of lighting fixtures, stage lighting has stricter requirements, especially in realistic dramas such as "Beijingers," "Teahouse," and "Thunderstorm," where lighting designs should hide fixtures as much as possible to avoid distracting the audience's view. Of course, some plays deliberately expose fixtures to create specific effects. In television lighting, the issue of exposed fixtures is relatively relaxed; for example, studio lighting equipment may be directly exposed, which relates to the structure and viewing methods of theaters and studios. Since the final image is determined by the camera, the cinematographer will avoid capturing exposed fixtures, so television lighting designers do not need to worry too much about this issue.

3.4 Use of Light Beams

Light beams are the paths of light, usually visible only in the presence of smoke and backlighting, and can be considered lines on the stage. As lines created by lighting that flow through space over time, beams can enhance rhythm and atmosphere when used appropriately. However, overuse can destroy the effect.

In television production, the use of light beams is more flexible, while in stage lighting, it requires more caution. Overuse of beams can distract the audience and disrupt the mood. Computer lights are widely used in both television and stage lighting due to their convenience, but they are highly controllable and prone to creating beams. Stage lighting designers must be careful when using computer lights and reduce the impact of unnecessary beams through functions like diffusion.

3.5 Application of "Hard Light" and "Soft Light"

In television lighting, especially studio lighting, the use of hard and soft light differs from stage lighting. Hard light refers to direct light with strong contrast, bright highlights, and sharp shadow edges; soft light refers to diffused light with less contrast, soft highlights, and gentle shadows. Drama school lighting design courses mainly focus on stage lighting, while TV studio lighting has its particular rules. For instance, small studio lighting for news and talk shows requires soft overall illumination to avoid harsh shadows and black zones, hence the common use of soft light.

The soft light used in stage lighting differs from that in television lighting; usually, thread spotlights known as "soft light lamps" are used for toplighting. However, if thread spotlights are used as front light in television lighting, the shadows will still appear quite hard, unsuitable for the image requirements of news or talk shows. Typically, such show front lighting uses lamps with stronger diffuse reflection effects, like three-base color soft lights, while thread spotlights are only used as backlights. The same type of fixture is applied differently in various contexts, and drama school graduates entering the field of television lighting need to adjust their use of fixtures accordingly.