Just as the arrival of the computer was meant to bring on the demise of paper, so in some circles it was felt that the arrival of the moving light in theatre would lead to the demise of the tedious process of focus plotting. After all, those motors and computers would mean that it would always take itself back to the correct place, right?

Well, no. Just as the paperless office has yet to arrive, moving lights actually take more work to focus plot since a light no longer just points to one place. If your show is going to run for any length of time or is going to move from venue to venue, you need to plot those positions. A replacement light never behaves identically to its predecessor, rigging positions do change on tour, and, even if your lights are ultra-reliable, there will come the day when the director demands to know why the light is in the wrong place. Unless you have documentation, it will be impossible for you to prove that the light is in the right place; it is just the actor that has moved!


So, the aim of focus plotting a rig is to ensure that the lights always go back to the same places, whether the next day, the next venue on tour, or on the next production around the world. With conventional lights, it's just a matter of stepping through each light one at a time and pointing them back in the right place. With moving lights, even doing that takes some work, and before considering focus plotting or even starting to program the show, there are some tricks which can help simplify the task.

In an ideal world, if every light was perfectly behaved, and the trusses were always in exactly the same place, then the lights would always point back to the right place, so first, aim to get as close to that ideal as you can in terms of rigging. Early VARI*LITE fixtures helped this with a “three point hang” — three hook clamps with one offset, rather than two — ensuring the lights were always hung level from the truss. There are now rigging systems available to help achieve this while hanging from two clamps. If not using those, make sure the position of the clamps are marked, and use a spirit level to make sure the light is hanging level.

Some lights then have built-in functionality to help you; you can adjust a “home” position built into the light to compensate for minor discrepancies in rigging. DHA's Digital Light Curtain first offered this facility, and many in the current Martin range offer this functionality from the unit's menu display, leading to the slightly strange idea of having to send someone up a lift to focus a moving light.

After that, you should aim to make use of any “preset focus,” “palette,” or “reference group” functions that your console-of-choice offers. These allow you to define positions which you then use in cues. So instead of pointing a light at the drummer then storing “pan 52%, tilt 48%” into cues, you'd store those values as a position preset called “drummer,” then store that preset into cues. It's more work at first, but when the drummer moves or you have to adjust the lights because the trusses have moved, you just re-focus the light and update the “drummer” position; all of the cues using that position then fix themselves. By making your cues from presets for position, iris, beam edge, and so on, you shouldn't have to touch the structure of your cues as you tour; merely update the components the cues are made from, provided you have a record of what those components should look like.

Even if using presets, there are different approaches you should consider. For example, some people will divide the stage into a grid then focus every light into every grid square, allowing them to get all of the lights to downstage-left by just selecting the “down-left” preset. I tend not to use this approach because actors always manage to stand on the join between two grid squares unless you have a lot of grid squares. Plus, if an actor's position changes from down-left to down-right, you have to select the appropriate grid square then track the new position through the relevant cues, and there's nothing in the console telling you why a light is set to a particular position.

I tend to make a number of general washes — a crosslight wash, a backlight wash, some gobo washes — then make other positions as they're needed. Some people who work this way will then take all of the lights they've set up for Scene 1 and record them into a position called “Scene 1,” but that, again, means that it's unclear what each light is doing. I tend to use presets almost as labels — “Character DL scene1,” “Door US,” “Statue MR” — since anyone operating the show later just has to look at the screen to get a good idea of what a light is meant to be doing.


Once your lights are set up and you've decided how to manage their focus presets, you still have to keep track of what the lights are doing while programming the show. With some moving light shows, this task falls to a person called the moving light tracker. This role goes back to the early days of programming moving lights with conventional desks without preset focus capabilities or consoles, such as the VARI*LITE Artisan, that offered cryptic preset names (“A1”) and no cue information displays. The only way of knowing what a light was set to in Cue 2 was to have it written down somewhere; the tracker did this quietly in the background, while the programmer programmed the show.

Different people devised a whole range of systems for doing this, usually using computers with some kind of database program; FileMaker® Pro software seems to have been the most popular choice. Lighting designer Ted Mather provided the examples shown here from some early moving light shows in the mid-80s to the early ‘90s: the track from the Broadway production of Aspects of Love [Figure 1], which was programmed using a non-moving-light console; the tracks from Chess on Broadway [Figure 2, 3] showing the focus of lights and the track of which lights were used in which cues; and the focus database from Beauty and the Beast [Figure 4], showing which lights where used in which focus, color, gobo, iris, and intensity on an Artisan. In many cases, the track worked per cue; the tracker was actually generating information that we would now expect to see on the screen of the lighting console. Position was then added, the aim being that the designer or programmer could later look at a patch of light on the stage and, from the track, know which moving light it was coming from.

The database for The Scarlet Pimpernel [Figure 5] was a very cunning example of this: click on any area of the stage or set, and a list of lights would pop-up; selecting one would leave its number on that part of the set. However, this still didn't record an accurate image of what the light looked like (beam edge, iris size) and meant the database had to be customized for each new show — fine when moving light shows were the big budget shows with lots of time but more problematic now that just about every show uses moving lights. (Incidentally, a warning: opening these older files was hard work because the software used to create or compress some of them is obsolete. Those working in rep situations where shows may come back years down the line, beware.)

Though some productions and some programmers still use a tracker, there is now less need because console features and displays have improved, and tools such as CAST Software's WYSIWYG have appeared. However, for long-running shows, there's still a need to accurately record what a light is doing: WYSIWYG will only show you what it thinks a light should be doing and still won't show you just how soft the gobo's focus was.


So, it still comes down to good, old-fashioned focus plotting. The traditional Broadway approach to this, with a person standing with their head in the hotspot of the light and then notating position on stage with coordinates such as “16L@+10” for 16' left of center, 10' upstage of the setting line, is well explained by John McKernon at his website, www.mckernon.com. Lightwright, his industry-standard tool for rig management, has good facilities for conventional focus plots. Sadly, it's less good when a light can be pointing to many different places, so different people have, again, developed different tools and techniques. What follows is the approach we've taken on a number of recent shows — including Mary Poppins in Bristol and London, UK tours of Rebecca, Dracula, and Highland Fling, and two recent productions for English National Opera. It describes the process as generically as possible but also, inevitably, includes descriptions of specific tools I've created to deal with these tasks. Perhaps we'll soon need a software programmer alongside the lighting programmer at the production desk.

For moving lights, the hard part is getting a list of the different positions in which each light is used. Without the aid of a tracker, my approach is to use the preset focus names coupled to memory to give me enough of a clue while programming the show; I don't want to hold up lighting sessions by pausing to notate lights. Besides, modern lights are quite reliable in the short term, and these positions will usually change very frequently until the show has settled down.

Traditionally, at some point — in previews or after the first night, depending on the timescale of the production — I've created a list of each preset used by each light in the show. Different consoles offer different aids to this, but at worst, it would mean manually trawling through the show in the console or an offline editor and recording which light was used in which focus in which cue (since the cue couples the position with the appropriate beam size, shape, and edge) in a database. I also used FileMaker Pro for this [Figure 6]. At the same time, I'd add what the light was actually doing in that position (“Fantine sings MC,” in Les Miserables), which may actually be of more importance than where the light is pointing, since if Fantine moved, the light would have to move with her, plus any scenery that the light was focused to, the trim of the lighting pipe for that focus if the trims change during the show, and so on.

That database provided the basis for a focus plotting session [Figure 7], carried out in a very traditional manner — standing on the stage, getting the right scenery set if the light tied in very specifically to a specific set, setting the light to the correct preset, recording the grid position, making a sketch of the light beam on a set drawing, repeating for the next preset position, then the next light. With a conventional rig, there's a sense of progress as you work through the channel numbers; with a moving rig, it was soul-destroying as you got up to channel 50, then started again on channel 1 in the next position!


Recently, however, two big changes have occurred. The first and most important is the arrival of high quality, reasonably priced digital cameras. Photographing each light in each focus (conventional or automated) has long been an aspiration but an impractical one because of the costs involved, the difficulty of cross-referencing photographs to lights, and the need to make duplicate sets of images. Digital cameras now let us do this without any real per-shot costs and with the ability to add the images to the focus database [Figure 8] and duplicate the information at will.

More importantly, the photographs provide a record not only of the light's position on stage but also of its beam size, beam edge (or gobo edge if used), gobo orientation [Figure 9], shutter shape for shuttering lights, and other parameters that are hard to record in written or sketched form. This includes how the light lands across complex three-dimensional scenery [Figure 10] but not color, since usually that information is available from the console, and having the light in open makes it easier to see in the picture.

Key to making this work is a good quality digital camera, though manual override of exposure, fast operation, long battery life, or a mains adaptor and a large memory card are more important than the highest megapixel count. Ted Mather and I first tried this process on Oklahoma! in New York using his Canon PowerShot S45, which worked well. I now use a Canon EOS 10D digital SLR; advantages are its 1GB memory card, a battery that seems to last forever, manual focus mode so I can lock the focus, and the ability to keep taking shots quickly. It's a 6-megapixel camera, but for focus shots, I set it to “medium small” — 1536×1024 resolution — since this still shows fixtures clearly without creating enormous image files.

The next vitally important thing is a tripod, since this lets you lock the camera to a fixed view as well as reducing camera shake. We generally set up the camera as high as possible while still able to see the full stage (so usually the front of an upper circle), fixed on a wide shot of the stage. We'll mark out a grid on the stage using tape or cloth [Figure 11] so that there's a reference to which we can compare the lights. On some shows, particularly with dance, the tape holding down the sections of dance floor may naturally provide this kind of grid. We'll experiment with houselights and worklights [Figure 12] so that there's enough light to see the light beam against the scenery — rather than darkness — and with exposure settings so that the image shows us everything we need to see. Exposure settings will vary according to lighting, set, camera, and lens, but what's important is to set the camera to manual, as having a bright spot of light in the middle of a dim stage will confuse any auto-exposure system. I often set the camera's film speed setting to the equivalent of ASA400, its aperture to about f2.8, and then work with a shutter speed of 1/10th-1/20th of a second. I'll record this information, together with the position of the camera (seating level and seat number) in case I have to match it in later shots. I'll also record other useful information, such a description of the grid (“centerline plus 1m marks L-R, 1m marks US-DS, DS line is plaster line, MS line is center of revolve,” for example) for the next time we have to focus the lights.

Where possible, we'll use a laptop with a wireless connection to the console to control the lights. We'll then have a person stand in each light as it comes on so we have a record of direction and angle [Figure 13, 14], even though the slowest part of this process becomes waiting for the person to move from light to light! Then, we just bring up each light in each focus from the list in the database, take the picture, move on to the next, ideally with the right scenery set if lights relate to particular scenic elements [Figure 15]. Failing that, a shot against a grid on an empty stage is better than nothing. The important thing is to keep a record of the order in which you're working through the presets and lights, so you can match the right picture to the right lamp/focus later on. This is particularly important if you have to skip a light along the way or if you decide to take some group shots (for example, showing how all of the lights in a gobo wash overlap [Figure 16]) as well as recording each light individually.

Since photographs are now effectively free, we'll also generally take full-stage shots of each cue state during a run of the show, so we have a record showing the light in context as well as in isolation [Figure 17]. We also take photos of the auditorium so we have a reminder of the front-of-house lighting positions the next time we do a show there!


Another recent radical change has been the creation of a new focus database, replacing the one I've used for the last eight years. This doesn't need specific customization for each new show; it also incorporates ways of extracting information from the lighting console automatically. Techniques for this will vary from console to console. I use ShowPort, a utility from Strand which will convert a Strand show file into a collection of text files. These files are fairly indecipherable to human beings. However, some work allows them to be imported into a database which can then extract useful information from them. I used to take a show into the offline editor and scan through it, manually typing cues, presets, and lights into the database before adding notes as to the lights function or photographs of the lights database. I now save the show file, transfer it to my laptop over the console network, run it through ShowPort, import the ShowPort files into the new database [Figure 18], and I immediately have a list [Figure 19] of each light, what that light is and where it's rigged (imported from Lightwright or similar), then each preset focus it's used in, what that preset is called, and which cues, effects, and submasters have that light on in that preset. Total time to achieve this? Minutes rather than several hours of tedious, error-prone work.

From this list, I can then step through each light focus, photographing it manually, or I can get the database to talk to the console, turn the light on in the right position and beam setting, trigger the camera, then move on to the next light [Figure 20]. When I then transfer the images from camera to computer, the database knows which image goes with which lamp/focus and imports them accordingly [Figure 21]. More importantly, if I add lights, cut lights, or change any positions, these will be automatically flagged the next time I import the show. The database then offers fields for other information that does still need to be entered manually. [Figure 22]

Achieving this has been quite hard work but well worth the effort; one wonders who will be the first lighting manufacturer to offer a way of integrating all of this information into the console itself.


Of course, this process still means having to find a suitable gap in the schedule, set up a camera upstairs, take the photographs, then pack everything away. At the London Coliseum for English National Opera, we're currently working to better integrate the process by installing a network webcam on the upper circle — connected via the building's Ethernet infrastructure to a laptop on the production desk — which will grab a picture every time a light is focused (or even provide an overhead view while focusing the light). We're also discussing permanently rigging a spotlight with a grid gobo to remove the need to run out focus tapes.


Of course, it's all very well for someone, whether it be the programmer, the lighting assistant, the tracker, or even the lighting designer, to record all of this information, but it's no good if they keep it all to themselves. The electricians running the show, in particular, will need the data.

You could leave it with them in paper form (if you could afford the ink cartridges for printing all of those pictures), or you could do a virtual print out to PDF, but those methods are very limiting because the information becomes static. On recent shows, we've left them with the database in fully working form by giving them the database file if they already have FileMaker Pro or creating a stand-alone version of the database using FileMaker Pro's Developer edition if they don't. This means that they can search and sort information; if Light 1 is swapped out, just search for all of things that Light 1 does and check those [Figure 23]. Or find everything used on the house set to do a focus check when that set is in. Or, if moving the show, just get the database to show you the lights used in each cue. Or, if touring quickly, work through the focus cues — cues that bundle the lights in their various focuses together as efficiently as possible. This is much more useful than thumbing through sheets of paper, and the database provides a check box, so you can keep a record of the lights you've focused.

Besides, leaving it on your computer uses less paper and so less trees, which must be a good thing, even if it's only a small step toward that paperless office.

Contact Rob Halliday at rob@robhalliday.com.