A Practical Guide to Stage Lighting, 2nd Edition

A Review

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11

to the near black leg remains in as much light as pos-

sible. Most units assigned to this function have beam

spreads ranging between 30 and 90°.

Combining the available instrumentation and the

needs of the production makes these kinds of gen-

eral height distinctions somewhat fuzzy. Any number

of instrument types and focuses can be specified for

each design. Most designers follow the guideline stat-

ing that instruments mounted at the top of the boom

focus to the far side, while lower-mounted instru-

ments focus to the near side. The focused beams don’t

“cross,” reducing the possibility of having too much

intensity between two overlapped light beams in the

same system.

Almost any instrument type can be used for boom

sidelight. When the light beams need to be shaped

with a sharp edge, ellipsoidal lighting instruments

are often the first choice. While other instrument

types are just as useful to produce sidelight, their

beams often require additional accessories to shape

the beams. This often translates into more time and

effort spent preparing or focusing them. In addition,

the combined weight of several accessories can alter

the boom’s center of balance, and may increase the

overall footprint of the sidelight position. If alternate

instruments are chosen for the job, then the amount

of scheduled time or space may need to be increased

in order to use them.

The successful boom sidelight system begins with

symmetry between positions. Regardless of what

instrument is used for each system, the unit type

should be the same and be mounted at the same ver-

tical height on each boom. Matching the unit type

means that kind of light will be the same throughout

the system. Matching the mounting height insures

that the focus angle will be duplicated in each open-

ing. Not only does this mean that the light source will

be consistent throughout the system; it also means the

performers will contend with the same vertical instru-

ment arrangement while running around the booms.

Next, successful boom sidelight instruments

attempt to be as compact as possible. Often this

translates into all the instruments being hung in the

same horizontal plane, one directly above, or below

the other. While some booms mount the instruments

directly upstage or downstage of the vertical support-

ing pipe, the even more compact booms reduce this

“thickness” by hanging the instruments onstage of

the vertical support. Not only does this often facilitate

focus, but it also translates into more space between

the boom and either of the masking legs for perform-

ers or other objects to pass around it. Sometimes the

instruments are double-hung, both sticking out on

either side. The phrase “double-hung” implies a pair

of instruments, both vertically mounted at the same

height. Obviously their combined width makes the

overall boom width “thicker.” In tight quarters, a typ-

ical plotting tactic is to restrict mounting double-hung

instruments to only above head height; single-hung

units are mounted from the floor to approximately

8′-0″, in order to provide as much passage space as

possible for performers or moving props between the

sidelight booms and masking legs.

Downlight

Downlight, or toplight, is generally defined as a

system, instrument, or light beam originating directly

above a person standing on a stage. The visual epit-

ome of downlight are shafts of light pointing straight

down, so that light covers the head and shoulders of

the person. The combined light beams form symmet-

rical pools, equidistantly overlapping left to right, and

up- and downstage. A full stage single-color down-

light wash typically covers the entire performance

area, from side to side, and from the upstage scenic

stack to head height at the downstage light line.

In reality, downlights rarely point straight down.

An overhead hanging position rarely gets placed

directly above each zone of focus points. In many

cases, the instruments end up on electrics that are

located in the up- or downstage side of an opening.

In order for the focused pools to appear properly

overlapped up- and downstage, the downlights are

slightly tipped during the focus to produce that effect.

Since this is one of the systems that is more obvious

to the audience’s angle of observation, however, care

must be taken during the plotting, the hang, and the

focus to create the illusion that the instruments are

focused “straight” down.

While the focus points for downlights in the first

zone can be centered in the middle of the opening,

they may just as easily be shifted upstage, so that

the downstage beam edges land close to the down-

stage light line. The focus points for downlights in

the final zone, on the other hand, are often shifted

downstage so that the upstage beam edges land at the

upstage light line. If the section is drawn so that accu-

rate trims and beam spreads of the instruments are

shown, it will be clearly seen where the beam edges

and focus points of intermediate zones will need to be

located, so that the pools symmetrically overlap.

The number of downlight zones, and the number

of instruments used in each zone, are unique for every

show. When a production is presented on an open

stage, however, the focus and symmetry of a downlight

system will be much more apparent to the audience’s

angle of observation. Depending on the overhead elec-

tric trim heights and the beam sizes used for the sys-

tem, the number of zones is often equal to or less than