Introduction to stage lighting equipment - the fresnel

Summary

This video from the Central Institute of Technology explores the Frel, a crucial theater lighting instrument known for its wash light capability. The Frel's evenly spread, softly focused light beam is attributed to the Fresnel lens, invented by French physicist Jean Austine. The video discusses essential accessories like barn doors and gel frames, emphasizing their roles in shaping and coloring the light. Safety measures, such as using rated rigging equipment and safety chains, are highlighted to prevent accidents. The tutorial also covers how to adjust the Frel's beam angle and focus without burning hands, showcasing its importance in creating stage washes and subtle highlighting effects.

Takeaways

• 🎭 The Fresnel (Frel) is a crucial component in theater lighting, known for its wash light capabilities.
• 🌟 The Fresnel lens, invented by French physicist Jean Austine Fresnel, is characterized by concentric circles that diffuse light for an even spread.
• 🖼️ Barn doors and gel frames are common accessories used with Fresnels to shape and color the light beam.
• 🔒 Safety is paramount in live events, with rated rigging equipment and safety chains used to prevent lighting fixtures from falling.
• 🧤 Incandescent lights like Fresnels can get very hot, requiring gloves for safe handling and adjustments.
• 🔧 The Fresnel has adjustable features like a locking nut for tilting, a handle for panning, and a zoom adjustment for beam angle, some of which have plastic coatings for safe operation.
• 👀 The soft, diffused edges of Fresnel lights are ideal for creating smooth transitions in lighting without drawing attention to the light source itself.
• 💡 Inside a Fresnel light, an incandescent bulb is used, which produces light by heating a thin filament.
• 📏 The lamp base's position within the casing controls the zoom feature, affecting the width of the light beam.
• 🎨 Fresnels are versatile, used for general stage lighting as well as for subtle highlighting of performers and scenic elements.

Q & A

What is the primary function of a Fresnel lens in theater lighting?

The Fresnel lens, also known as a frel, is the workhorse of the theater lighting system. It provides an evenly spread beam of light that can be focused to be wider or more narrow, with softly focused edges, making it ideal for creating washes of light across the stage.

Who invented the Fresnel lens and what is its significance?

The Fresnel lens was invented by French physicist Jean Austine Fresnel. The lens is significant for its concentric circles that diffuse the light beam, giving a nice even spread of intensity and softly focused edges, which are characteristic of wash lights.

What are the common accessories used with Fresnel lights in theater setups?

Common accessories used with Fresnel lights include barn doors, which help control the spread of the light, and gel frames, which allow for coloration of the light beam. These accessories enhance the versatility of the Fresnel lights in creating various lighting effects.

What safety measures are recommended when using lighting equipment suspended over people's heads?

To ensure safety, only rated rigging equipment should be used, and safety chains or safeties should be added to the lights. These chains clip onto the light and the bar above, ensuring that even if the rigging fails, the light remains in place and does not fall.

How do you handle the heat generated by incandescent lights like the Fresnel during live events?

Incandescent lights, such as the Fresnel, can get very hot. To avoid burns, it's recommended to use gloves when adjusting the lights. There are also specific adjustments on the Fresnel, like the locking nut for tilting and the handle for panning, which have plastic coatings allowing for safe handling without gloves.

What adjustments can be made to the Fresnel light to control the beam angle?

The Fresnel light allows for adjustments to control the beam angle. There is a locking nut to tilt the light for angle adjustments, a handle to pan the light, and a zoom adjustment to control the beam angle in and out, allowing for precise focusing of the light.

How does the Fresnel lens achieve the zoom feature to change the beam angle?

The Fresnel lens achieves the zoom feature by having a lamp base that slides back and forth inside the casing. When the lamp base is towards the rear of the lighting fixture, it produces a narrow beam. As the lamp base slides towards the front, the beam angle widens.

What is the typical use of Fresnel lights in theater and live events?

Fresnel lights are used for standard and essential lighting effects such as stage washes and for creating subtle highlighting of performers and scenery elements. Their even brightness and softly focused edges make them ideal for these purposes.

How does the Fresnel lens contribute to the overall lighting design in theater?

The Fresnel lens contributes to theater lighting design by providing a wash light with an even brightness across the beam angle and softly focused edges, which helps draw attention to the subject rather than the light source itself.

What are the characteristics of a well-functioning Fresnel light in terms of its beam?

A well-functioning Fresnel light is characterized by a very even brightness across the beam angle and a softly focused edge, which means there is a gradual change from full brightness to nothing at the edge of the beam, avoiding sharp edges that can draw attention away from the stage.