Stage Lanterns and Control Equipment

Stage Lanterns

These are the basic types of lantern for general stage lighting.

Flood

Floods have no lens and there is no control over the beam of light, but you can fit a coloured gel. They are most often used to illuminate backcloths and cycloramas. Usually 300 or 500 watt.

The model shown is a conventional flood for illuminating from above the stage. There are variants designed to be placed on the floor (in single and multiple units) to illuminate cycloramas, etc, from below.

Fresnel

Sliding the lamp tray assembly using the knob underneath controls the beam angle. The lens has concentric rings of ridges that give a soft edged beam. A rotating Barndoor (as illustrated) can be fitted to shape the beam. Available in 500w, 650w, 1kw, 1.2kw or 2kw.

Generally only used behind the proscenium arch or on the first bar immediately in front of it as they have a wide beam angle (relative to a Profile) and tend to spill light due to the nature of the lens.

Pebble Convex

This lantern uses a modified plano-convex lens with a pebbled effect on the flat (plano) side, to create a beam similar to the Fresnel, but with a slightly harder edge. There is a focussing knob to change the beam angle. Available in 500w, 650w, 1kw, 1.2kw or 2kw.

Often used in place of a Profile lantern if space is limited.

Profile

The beam angle is adjusted by moving the lens using the knob underneath. A plano-convex lens gives a sharp edged beam. Four shutters are fitted to shape the beam. Available in 500w, 650w, 1kw, 1.2kw or 2kw. A Bifocal Profile has two sets of shutters to give hard and soft edges.

Almost exclusively used in front of house positions.

Par Can

Par Cans are not usually preferred for normal stage lighting but are often used for special effects or for lighting musicians. There is no lens or reflector in the lantern housing and the beam angle can not be changed. Instead a fixed beam parabolic reflector lamp is used. "PAR56" types are usually 300 or 500 watts, "PAR64" types are usually 500 or 1000 watts.

The lamps are available in a small number of fixed beams widths giving a narrow, medium or wide beam, relative to the distance from the stage. They can be very effective when used for backlighting.

Lighting Control

Stage lanterns are usually controlled by one or more dimmer packs connected to a control desk.

Control Desk

This desk has two control presets of 12 channels each with master faders. Each channel also has a "flash" button. The faders are usually graduated in half steps from 0 to 10. Some larger professional systems are graduated in percent.

Dimmer Pack

This dimmer pack has two sockets per channel for connecting the stage lanterns. Some packs are permanently wired to outlet sockets around the stage and auditorium, but this is not usually so convenient.

Cables

The mains cables for stage use are usually round-pin 16 amp, 15 amp, or sometimes 5 amp type. These types of plugs do not contain fuses, so that however many extension cables and adaptors you use the only fuse in the circuit will be easily accessible at the dimmer pack. If conventional 13 amp mains connectors were used it would be difficult to find and replace a blown fuse.

Lighting desks are connected to the dimmer packs by one or more low voltage multi-pin cables.

Accessories

Gel

Any lantern can have gel fitted to change the colour of the light, often in a separate gel frame. Gel is usually supplied in sheets about 24 inches by 36 inches and the colours are usually referred to by numbers as well as more descriptive names; e.g.: 10: Medium Yellow, 24: Scarlet, 57: Lavender, 89: Moss Green. Modern gel is flame retardant, older types could melt and give off smoke and fumes. However over time the gel will loose its colouring if used frequently.

Barndoor

A Barndoor can be fitted to the front of a Fresnel lantern to give some control over the shape of the beam. The assembly is designed so that the four door flaps rotate to enable you to adjust them to the best position. It can only lop off soft straight edges, but with some patience you can usually gat a reasonable result.

Gobo

Gobos are flat metal discs that are often used for creating abstract effects. When fitted in the appropriate holder for the model of lantern, the holder assembly drops in to the slot in the "gate" of a Profile lantern just behind the shutter plane. A single gobo projects a simple silhouette, more complicated images are achieved by placing several complimentary gobos in different lanterns. Typical gobo patterns are clouds, church windows, skyscrapers and flags.

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