FocusTrack - from
the ABTT’s
Sightline Magazine
by
Rob Halliday
When I was very much younger, just starting out
playing with moving lights, there were two things I
assumed were true. Firstly, that one moving light
would behave the same as another, so you could swap
one out without having any effect on the show.
Secondly, that my memory was good enough to keep
track of what all of the lights did during the show
not just in tech but when returning months or
(hopefully) years later.
Turns out, neither of those things are true. Even
lights of the same kind often display subtle
differences, particularly with edge focus, shutter
shape or gobo orientation. Tiny rigging differences
can lead to large position differences when magnified
by long throws. And one's memory isn't as good as one
hopes, and gets no better with age...
With conventional lights, we've always had to record
a light's focus in order to accurately maintain or
re-create it. American associate lighting designers
specialise in exactly this - 'hotspot 6L@+3' plus
perhaps a little sketch.
Of course, each conventional only has one focus.
Moving lights have many. Their motors mean they can
attempt to get back to those focuses - put the lights
in the same positions in a new venue, load the disc
and you'll get a fair approximation of the lighting.
But the devil is in the detail - is the edge just as
it was, are the shutters exactly right? If the rig
isn't hanging in exactly the same place, more fixes
will be needed. Have to change to a different type of
light and the challenge becomes even greater.
All of which leads to the conclusion that if a show
is going to have any kind of life, the moving lights
need to be focus plotted just as much as the
conventionals - perhaps more, since an incorrectly
focussed conventional is wrong once, an incorrectly
set moving light wrong many times. An accurate record
is good for me as the programmer, great for the crew
I hand a show over to, and fantastic for the lighting
designer - a permanent record of the show for their
archive.
In America, land of paperwork, this has traditionally
been achieved by employing a moving light tracker -
someone sitting next to the programmer, manually
recording each focus. In part this was through
necessity: the early Vari-Lite Artisan console gave
little feedback, with no "1@50, down centre" channel
display. You really had to write things down if you
needed to edit the show later.
Later consoles seemed to change the approach
required. The screen would show what each light was
meant to be doing, particularly if preset focuses
were clearly named. I could certainly remember the
actual focus through the tech process. Given that,
notating hundreds of focuses that might end up not
being used seemed wasteful - as did pausing to write
things down during the tech, usually the most
time-constrained period of getting a show on.
My approach became to concentrate on programming the
show then, when nearly done, to take the showfile
into an off-line editor and manually work through it
light by light, making a note of which light used
which focus. It was tedious and time consuming, and
every time I did it I thought "aren't computers meant
to save us from this kind of dull, repetitive job?"
But there was always a deadline, and it always seemed
safer to just get the job done than try to figure out
a better way of doing it.
List in hand, we'd then work through each light's
focuses, recording them firstly (circa 1997) with
sketches and descriptions, later (from circa 2001)
with digital photographs. It was a frustrating task:
there's a sense of progress to focus plotting a
conventional rig, start at channel 1, go to channel
200, job done. With moving lights you start at 1, go
to 30, then start again. And again. And again.
Which is why finally, on some big show with time to
spare, I started exploring alternatives. This was the
start of FocusTrack.
The aim was to take the showfile from the console and
have a computer figure out which focus positions each
light was used in. 'Used' turned out to be a tricksy
word: it first meant 'in this position with the light
actually on', and later evolved to include 'moving
from this position as a light is fading in, or to
this position as fading out', since in both cases the
position is part of the overall look of the show.
Along the way I realised that the same test was
useful for more than just position - which scroller
colours or moving light gobos were actually used?
FocusTrack can now achieve all of those things and
more.
So, how do you use it? In effect, you get your
showfile data out of your console (ETC Eos family, MA
grandMA or Strand 500-series) then tell FocusTrack to
import that data. You specify the cue lists or cue
range you're interested in, and a minimum level you
consider on (so cues where lights are just
pre-heating don't get counted). FocusTrack then
ponders things for a while - seconds for small shows,
possibly hours for really big shows in which case you
set it to work and go to dinner, or to bed.
Import complete, you get three sets of information.
Cue List shows you your cues from the console, but
with space to add more information and the ability to
better reveal the structure of the show by
highlighting the start of scenes, and to show or hide
cue parts. RigTrack has the information about your
rig - channel 4 is patched to address 308 and is a
VL3000; you can add other information to this
('rigged on LX4') either by hand or by importing from
Lightwright, VectorWorks Spotlight or other sources.
FocusTrack lists each position that each light is
actually used in. On big shows that seems to average
about 12 positions per light, so with 50 lights that
might be 600 of what I call 'lamp-focuses'. If you
add more information to Cue List - when scenes start
or scenery appears on stage - FocusTrack can
cross-reference this to work out which lamp-focuses
are used in particular scenes or with particularly
scenery.
This means you now know how each light is used. But
you'd still want to create a record of what each
light actually looked like in each position.
FocusTrack helps with this by talking to the console
and your camera: run on a Macintosh, it can turn each
light on in each position and then tell you to take a
picture or just trigger the camera directly. The
process of photographing each focus becomes
incredibly fast because you're not having to look up
the information then tell a console operator which
light to bring up, with all of the possibilities for
error in that process. Big shows regularly take 1500
or more pictures in an eight hour session - averaging
a photo every 15 seconds, including waiting for
scenery to be shifted and, ideally, for someone to
move into the light as a reference for direction and
angle. You can add pictures of whole washes, of
conventional focuses, and of cues, to give you a
complete record of every building block of the
lighting and the end result.
You can then access that information however you like
- by channel when swapping out a light, by scene or
set during rehearsals, or even by cue. This is great
when checking a show over a dress run (or a first
night on tour!), FocusTrack walking you through the
focus either listing every light in every cue or just
focuses the first time they appear, since the next
time you'll hopefully already have got the focus
fixed.
It can also help you prepare for that tour: because
it has the whole showfile behind it, it can tell you
which lights never come on (so you can cut them),
which colours and gobos are used (so you can shrink
your scrolls or try different colours), and which
focuses for a light are similar or identical to other
focuses (allowing you to merge focuses to make
updating everything in each venue speedier). It can
even have a reasonable stab at calculating power
loads per cue or power consumption through the show.
As it evolves, new tools have appeared - a way of
notating focuses by cue as you make them if you want
to work 'American' style, or generating summaries of
what cues actually do ('blue backlight gets brighter,
red crosslight goes out') which opera and ballet
designers crave when re-creating shows in new venues
with completely different rigs. Plus it has a
selection of tools for managing the rig once it's up
and running - tracking faults and maintenance on
fixtures, lamp-hour totals and more.
It is by no means perfect, but I think it's an
interesting and useful tool that is invaluable on
shows that have - or hope for - a long life. If
you're interested, it's available for you to download and try for
yourself.