Lights: an Introduction to Instruments

Lesson 1 — Lights: an Introduction to Instruments



Students will be able to identify different types of lights and their purposes by filling out an equipment worksheet.  Lesson 1.Lighting Reference Sheet


National Standards:

TH:Cr1.1.I.b. Explore the impact of technology on design choices in a drama/theatre work.

TH:Cr1.1.I.a. Apply basic research to construct ideas about the visual composition of a drama/theatre work.



1 fresnel, 1 par, 1 ellipsoidal, several barrels, gels in frames, gobos in frames, cables, copies of worksheet for the class


Prepare before class: Have lights and equipment set up at the front of the classroom.


Hook: Ask the class if they know the names of the fixtures on the stage. These are the basic units of lighting work and design. Hand out worksheet (see end of lesson) to students.


Step 1: Fresnels

Show students Fresnel. Point out housing, lamp, cable, lens, reflector, yoke, c-clamp, and gel clip. The Fresnel is used for wide pools of light; usually in general washes across the stage and top light. Barn doors can be used to cut light off of legs, scenery, and other areas.


Step 2: PAR cans

Show students PAR. PAR stands for Parabolic Aluminized Reflector. Point out the differences between the Fresnel and the PAR, namely the style of lamp base, lens and how the light sits in the housing. Lenses are interchangeable on most PARs, specifically on Source Four instruments. They usually range between Extra Wide and Narrow, and the difference lies in the shape of the lens, which changes the light pool shape. You can also use barn doors on PAR lights.


Step 3: Ellipsoidal

Use Source Four ellipsoidal, if available. Point out differences between the ellipsoidal and other lights, namely the shape, shutters, barrel, and focusing abilities. Explain that this is due to the shape of the reflector, which is an ellipsis that has a point of focus in the housing. When you move the lens, you move it closer or farther away from that point, bringing it in or out of focus.


Show other barrels. The different degree of barrel indicates how wide the beam of light coming from the instrument is. This means that a 10° barrel will let out 10° of light, and a 90° barrel will let out a full 90° of light. This is important, because it changes how it is used in the space. Using a light with a 10° barrel in a small space can be impractical if you are trying to creating acting areas, because it will not let out enough light, while using a 90° in a large space would let out too much light that could either a) spill out into the space, or b) become diffused and ineffective. The most common barrels used in the size of spaces we have in this school are 26°, 36° and 50° barrels.


Step 4: Cables

Extension cables – Depending on the space you are in, extension cables are often sold and made in different lengths. Longer cable lengths can be upward of 100’, and can be as small as 6”. Anything smaller than 5’ is called a jumper. Here we use two types of cables, Edison and twist-lock. If you want to change between the two you need an adapter. There are more connector types, the most important one being stage pin, which looks like a flat box with three cylindrical pins sticking up out of it.


Two-fers and three-fers – Sometimes to conserve dimmers, we will plug two lights into the same outlet. This is accomplished through using a two-fer. It is important to check and make sure that the lights you are using can be two-fered, so you don’t blow a fuse or damage your equipment, but connecting two pars or ellipsoidals usually isn’t a problem. Part of the job of a master electrician is to know the demands of the lights on power and make sure that we don’t put too much electrical load on a system. When lights are two-fered together, they cannot function independently. That means if you bring up that dimmer, two lights will turn on.


Dimmer doubler – The only way to change this is by using a dimmer doubler. Dimmer doublers are able to split the dimmer voltage output and let lights be controlled independently of each other, but they need to use a special 77V lamp in order to do so. We also have to take a couple extra steps while programming at the light board and on the dimmer rack, which controls the intensity, or brightness, of the lights.


Step 5: Gels and Gobos

Gels: These are plastic sheets used to color light. They come in a variety of colors. Some gels are clear, but have texture. These are called frost, and are used to change the quality of the light, usually to make it softer or look out of focus. Frost can also stretch the light in different directions, much like the lens of a PAR. Gels are put into gel frames, then slipped into the light right at the font of the lens. Gel frames should be securely clipped in place. Gels got their name from their original source material, thin sheets of colored gelatin.


Gobos: These are discs of metal that have holes cut in them to let light through. Demonstrate to the students how the gobo is inserted first into the gobo holder, then into the gobo slot. Glass gobos should be put into a glass gobo frame, then put into the larger accessory slot. Never put a glass gobo into the gobo slot on a light. It will get stuck.


Conclusion: Questions and Answers

Let the students come up and look at the lighting equipment and ask any questions they might have. Ask them questions about the lights to assess comprehension.


Note: Make sure to ask students questions throughout the lesson. If they know information about the lights, let them talk about them, providing correction or supplementary information where necessary. You may consider asking more advanced students to introduce the lights and their functions, rather than doing it yourself.