Drafting a Preliminary Lightplot
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Drafting a Preliminary Lightplot

Drafting a Preliminary Lightplot

This segment, and the next (Drawing a Lightplot) already assumes you understand the basics of drawing a drafting. If you haven't yet: please consider going through the segment Designer's Tool: Drafting before continuing.

This segment is a continuation of using the rough plot we created for “Foxhole” on the last page.
Previously created resource: Rough Plot
Foxhole Rough Plot View Larger
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Previously created resource: Color Key
Foxhole Color Key View Larger
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When placing the instruments on your plot, be sure to keep in mind instrument throw distance and scenic sections; discussed separately.

This Throw Chart is available as an easy-to-print PDF.

This (highlighted in blue) range of instruments would be our ideal choices for this production in this theatre. We can compare these to our inventory to narrow our selection (or determine what equipment is needed to rent).

Earlier our section showed us that instruments will be about 20'-0" away from their area of focus. Our lighting areas were planned as 8'-0" circles.

Especially when you’re drawing a Lightplot early in your career; I recommend creating a “rough plot” (previously covered) on a copy of a scale groundplan.

Then; use a sheet of vellum laid over your rough plot to use your rough as a guide for actually drafting your first (preliminary) plot. With the knowledge that this won’t be your final (submitted) Lightplot; you can draw more at ease knowing that your line weights and any mistakes won’t be seen by others.

After you’re done with this preliminary plot, and comparing it to your rough plot and notes to find and correct as many mistakes as possible: you can then trace that onto your final Lightplot.

When drafting a lightplot, it is allowable to draw all of the units facing one direction or rotating them somewhat to indicate their direction of focus. Although rotating the units takes longer to draw, it can help the designer spot potential problems early, and helps the electricians hang the plot more accurately; so rotating them is the recommended practice.

Lighting instruments should rarely be placed closer than 18” apart. When they are placed “tighter” than that; they often get in each other’s way when focusing. Extra room should be allotted for units with barndoors, or which will be focused as sidelight.
1st Electric from rough to preliminary.
Using the throw chart above, I can deduce that 6x12’s would be the most ideal lighting instrument for all of the lights on a pipe 20’ above the stage; so I’m drawing a leko with a single slash to indicate the unit type, and writing the color and focus area notes to make it easy to copy when drawing my final plot. At this point I wouldn’t ordinarily number the instruments – I’m including them here for clarity.
  1. Technically I want the (4) high side units at the end of the pipe.
  2. Although it looks like it will work on paper, it won't in the theatre.
  3. Units need to be at least 18” apart under normal circumstances.
  4. Because most of these units will be hung parallel with the pipe, however, they should be hung at least 24” apart.

There are two accepted formats for drawing booms (pipes that are in vertical positions usually standing on a large round base). I’ll demonstrate both methods here; one for each side of the stage – although I usually wouldn’t mix the two formats on a single drafting.
Boom method 1: SL
The first method is to
  • Draw a side view of the boom, indicating the height and attributes for each unit hung on that boom. This drawing can happen in place, or in another location on the page that has the space for it.
  • Draw a shaded unit (with a boom base around it) where the boom should be located.
* Because all three of the booms on stage left are the same configuration, I only need to draw one. If the booms were different, I’d need to draw one for each style.
Boom method 2 SRThe second method is to draw the boom base in place, with the unit on top of it.

*This style is limited to booms with only one light on them; if there were more instruments, they would appear “stacked” on the drawing and it would become confusing.

Personally, I prefer the first method.

When you are done figuring out where all of your lighting instruments should go, take another look at the ground plan to see if you may have forgotten something on the set – do you need to light the walls at all?

In this example I have added far cyc units to light the cyclorama (which serves as “the sky”) upstage.
Can you see a window, doorway or archway that doesn’t have a light upstage of it? If so, you may have forgotten to light those important indicators that the world doesn’t end with the upstage wall of the set.

Quick check: count how many lights are indicated for each position (1st elec, 2nd elec, etc) on your rough plot and see if you have that many on each position on your preliminary plot. There should be at minimum the same amount.