Designer's Tool: The Lightplot
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Using the Groundplan & Color Keys to Create a Lightplot

The lightplot is the primary communication tool that the designer has for dealing with the electricians. Therefore the lightplot must clearly explain where the lights are to be placed and how they should be circuited, colored, and generally focused.
Often times the lighting designer is not present for a “load-in” or light hang call, and there’s too much information that needs to be communicated to rely on verbal skills.

When preparing to work on the lightplot, you should be totally familiar with the play and your production’s specific needs.

* If you haven't checked out the "Foxhole" project (a two-page play) available on this site, please consider doing so before proceeding - as it may help you understand some of the choices and decisions I'll be making throughout this segment.

You should have already analyzed the play and figured out the color key(s) needed for the project.

You must also have a thorough understanding of the set, and at least a general concept of how the actors use the set. Is there much movement? Do they do “direct addresses” (when they talk directly to the audience) from a specific area on stage?

This is an example of the type of groundplan a lighting designer can expect to receive from the set designer. The theatre and set should be indicated in scale, but it may not include additional information (like where the electrics are)!

So, along with the color key, you should have created a list of whatever “specials” are called for by either the actors or the set.

Perhaps you need to indicate a window as part of the “fourth wall” (an expression that refers to the invisible barrier between performers and the audience - typically in a proscenium theatre).

Next: The groundplan for this production of "How I Learned to Drive" did not indicate a wall (or a window). The scene was two people talking briefly as the Uncle washed dishes, and the actors were standing downstage of one of the main platforms which had the living room scenery. I added the window gobo to help further isolate the two actors giving them additional privacy while reinforcing that they were "inside" the house.
How I Learned to Drive production photo

How I Learned to Drive production photo by scenic and lighting designer Kade Mendelowitz

With this knowledge, mark up a groundplan with 8’ acting areas. We tend to plan 8’ areas because that offers enough room for two actors to have a small scene in, a single actor to move around somewhat, and yet is small enough that you can still have enough control to “focus down” on a particular area if needed during cueing.
Pay attention, as you mark up the groundplan, to how the movement or blocking of the production flows. Not all of these areas are necessary for this production, because the actors don’t ever head upstage (area “O” for example).

Although a piece of furniture may not fit neatly into you preliminary layout of areas, you are almost guaranteed that certain types of furniture (couch, table or entryway) will need its own lighting area.
In this particular case: the barriers are very important; so areas should be adjusted to accommodate actors hiding "behind" them.

Well-planned acting areas can work with your specials to give you a lot of built-in flexibility when you sit down and begin to write your cues.

You may need to add an area or “cheat” some areas in order to make a layout that creates adequate coverage and (if dimmered properly) can supply you with enough control to most effectively design different moments in a production.

Notice how few lighting areas are needed to adequately light this particular production. This information was supplied by the script, and was exemplified in the videotaped rehearsal that is available.
If your specials are the only means you have to isolate areas, then you are forced to always use your specials for major events. But, if your area lights have good control built in to them; they can add more variables and opportunities when cueing.
Color Key updated
Color key with specials
A few things to note:
  • Lighting designers use letters to keep track of lighting areas because numbers are used for so many other things (unit numbers, channels, gels, etc.).
  • When possible, it’s best to skip using the letter “I” (i) when marking areas because it can easily be confused for the number “1”.
  • Areas (and unit numbers) are laid out from stage left (SL) to stage right (SR) so that they can be read correctly when standing on stage (similar to stage directions).
  • Lighting areas need to overlap so that the light from the “field angle” potion of the beams overlap – making the light appear smooth and consistent from one area to another. Beam angles are the brightest portion of the light beam.
Get a copy of the plans for the theatre you’re going to be working in, and a list of available equipment. Most productions take place in a space that has been used as a performance space before; with lighting positions and an equipment inventory that will be available to you. If that is not the case; you will have to make those decisions and specify even the pipes and hanging positions you want to use – and it will need to be rented; such is how the Broadway theatres work: they are essentially very pretty boxes.
You need to know where electrical pipes are, and what their “trim” (height at which they are hung) are.
Groundplan supplied by set designer
Groundplan supplied by the theatre
Be sure to get one with the placement of electrics indicated.
Also ask if there's any kind of breakdown of where circuits are located. Sometimes they are on the drafting, sometimes they're part of a paperwork packet.
Foxhole Wingless Theatre
View PDF
Oftentimes you will have to combine the two groundplans together; adding electrics/pipes to the set designer's plans.

Adjusting Color Keys to the Budget

See if any of the color key elements can be condensed.
Especially if equipment, whether it be dimmers or instruments, is in short supply; you can often combine downlights, backlights, or even at least one front light can be used for “double duty”.
Although the set may not change from Act I to Act II, if the time of day has changed, for example, you may find that you want to hang essentially two separate light plots; one for each time of day. That is often cost or time prohibitive.

Original Daytime Color Key
A) Perhaps you’re lighting a play which calls for a certain type of daylight, and this is the color key you come up with.
Original Nighttime Color Key
B) Act II has a romantic evening vibe, and you come up with this color key.
Original Combined Color Key
C) The lighting would require a combined color key like this – which is a reasonable and common scenario.
D) If the budget won’t allow for seven lights per area, however, one must come up with a reduced combined color key that can achieve similarly flexible results.

Hanging two sets of lights per area (example: three-light system for “daytime” and a four-light system for “nighttime”) is often cost or time prohibitive; you may be able to device a four-light system with one front light position “double-hung” (two lights from essentially the same position) to create a similar effect.

Reduced Daytime Color Key
E) This is just one possible example, and though the lighting from the top (your original idea) is not duplicated; the essence of the cues from the reduced combined key may work for your needs.
Reduced Nighttime Color Key
Reduced Combined Color Key

Trouble viewing the video? Watch it directly on Vimeo.

The video demonstrates that you use the color key you’ve developed and apply it to the areas you’ve marked out on the groundplan. This video gives you a general sense of where the lights will need to be placed – more detail follows in the next segment with “sections”.