Intelligent Lighting

Fixture Personality Files and Lighting Control

This rough guide looks at the different functions of fixture personality files, trends in complex lighting control interfaces and asks “When is standardisation going to replace fragmentation in the world of stage lighting control?”

Fixture Personality Basics

Intelligent lighting equipment that requires multiple parameters of control has a model specific map of how those functions are controlled. If a fixture requires 30 channels of control, perhaps the first channel is mapped to Intensity with Pan Coarse on channel 3. The other 28 channels all have their own functions including colours, shutters and focus.

The table of channel control functions is not only manufacturer and model specific, but many fixtures also sport a number of control modes that can alter the mapping. Maybe Mode 1 uses channel 4 to control Tilt, while in Mode 3 Tilt appears on channel 3.

The way control channels, commonly DMX addresses, affect the parameters of a specific fixture type is basis of the Fixture Personality.


How do we use Fixture Personality data?

Using a simple DMX preset style desk, knowing the personality of a certain fixture tells us which faders the different attributes. So, we know that fader 1 will control Intensity, for example. But who wants to control complex lighting fixtures using a preset desk? Not me.

Every intelligent lighting control needs personality data to function properly. At it’s simplest, the console needs to know how to assign control channels to the different parts of the desk – Intensity to faders, Pan and Tilt to the position controls etc. When you select Gobo control, it’s no good finding the encoders are adjusting Prism.

So, the console needs to know the personality of the fixture types and these are commonly stored in a library of Fixture Personality files and set during the desk patching process. Currently, fixture personality file formats are proprietary to the specific console manufacturer. This bugs me but more about that later.

Other Fixture Personality File Data Use

So far, we’ve looked at the way a fixture personality file is used to map the different control channels to the interface of the console. This is only a part of it’s use.

Range table data – Some attributes of an intelligent fixture perform different actions depend on their set channel level, for 0 to 255. While parameters such as dimmer, pan and tilt change on a linear scale based on level setting, other parameters such as gobo or colour wheels have set positions that clunk through based on a range of control level. The Open White slot in a colour wheel might be recalled by Colour Wheel 1 > Level between 0 – 17. If your console fiddling experience is to be a positive one, the desk needs to know this.

Control channels can adjust some varied functions depending on range of channel level. Perhaps the macro to Lamp Off the fixture is fired using a Shutter > Level between 220 to 255, you don’t want this happening by accident but you do want to be able to Lamp On using the pre set macro at the console. Range table data within the fixture personality file sorts this out.

Auto Palettes – Patching up a new set of fixtures, you ask the console to generate some standard palettes to get started. White, Red, Amber, Gobo 1, Gobo 2 the list goes on. Using the range table s and other personality file data, the console is able to speed up the building of the blocks by automating some of the process.

The Future of Personality Files

While we are still working with a system that uses a Control Channel / Channel Level and different lighting fixtures exist in the market, fixture personality files will continue to evolve. The latest generation of top end lighting consoles have developed some clever techniques such as integrated colour setting whether CMY, RGB or HSB and Fixture Morphing (attempting to exchange one make of fixture for another with losing your programming). Many of these functions rely heavily on even more advanced fixture personality files and the processing of that data.

This brings me to a personal bug bear of mine.

Anyone who knows me well will know that I have been banging on for years about the benefits of standardising fixture personality files. Here are some of my beefs with the currently proprietary personality formats:

  • Not portable between platforms like consoles and visualisers.
  • They take console makers valuable time to create. This can makes the personalities released poor quality, with errors and omissions in functionality.
  • Fixture makers can change mapping and mode specs. More time spent updating files for every desk maker.
  • New fixtures are being added to the market at a furious rate. Every CheepoSpot fixture needs a personality file for the four guys in the world that use the darn things.

The whole thing is so inefficient – why are we creating hundreds of different file types for different consoles and software when the fixture manufacturer could create one – just one personality file. And the correct one. And update it when they changed their firmware. Having proprietary personality files just seems like such a waste of everyone’s time.

Will it ever happen? Will the industry unite around some kind of XML personality file that will fulfil the needs of the simplest control desk and the worlds biggest lighting console?

The lighting business has agreed on DMX512 and the ARTNet protocol is one of a number of widely adopted standards that have been integrated into control equipment. The current mess is the confusion between different media servers and two way communication with different consoles. Getting media thumbnails displayed and other vital tools. But there may be hope on the horizon.

In reality, once one feature has appeared on one console it soon filters down to other makes BUT it is then implemented in each desk makers own “special” way. Let’s face it, the output of a lighting console ends up the same, no matter what gubbins gets between the human and the fixtures. The console makers are only really selling the interface, after all. Surely the differentiation between control only needs to be the interface and the level of functionality

The trouble with an ever more fragmented lighting control market is everyone is so busy trying to differentiate their own product that it sometimes seems like we are getting further from standardisation and away from efficient development.

As each console relies on increasingly advanced personality files, hopes of an integrated standard single file for fixture personality data seems to get further away?

Perhaps the next generation of lighting technologists, the On Stage Lighting readers, will take on the challenge of better standardisation in future lighting control. If you are keen, you might like to take a look at the details of ESTAs ACN (Architecture for Control Networks).

OK, so we’ve taken a quick tour of fixture personality data and you’ve waited patiently while I had a minor rant about standardisation in entertainment technology. Oh, and we have spotted the ACN cavalry far off in the distance. Hopefully, you will have a bit more of an understanding of another vital tool in modern stage lighting – fixture personality data.

With any luck, future development and adoption of ACN will sort out the communication of individual fixture personalities (assume somthing like an XML file), but in the meantime we are stuck with fixture personality files for a while yet.

If you have any thoughts on how the lighting industry should emerge from the sheds and into the 21st century world of development, put your comments in the box below.

Image by Samuel Stroubes

  1. Paul Pelletier

    Great article Rob!

    Indeed we need a standardized fixture personality format.
    The amount of money spent every year by controller manufacturer to maintain such libraries and with the wave of copycat fixtures from China, I think it is time to have this standard and let the fixture manufacturer to supply the fixture profile.

    XML would be the ideal choice for this.
    For example, the Martin Maxxyz family already use an open XML format that could be used to set the base of such standard. Also work made by Carallon and Grand MA on their fixture library format should also be of a great help.

    One of the important feature for example is to standardize the parameters name so for example Intensity is always called intensity and not dimmer, douser, output or whatever else…
    What does it matter…. for good multi-type selection and fixture cloning….
    Such list could be maintain dynamically and reviewed once a year

    Years ago I did email ESTA regarding this, but I was told it was outside their scope and would only serve a few manufacturer…. I hope this point of view has changed now.

    Paul Pelletier

    Commercial Product Manager – Controllers

    Martin Professional A/S

  2. Paul Pelletier

    The Martin XML format is also open and free.

    Soon a publique fixture editor will be available.

    One advantage of this XML format is the ability to define fixture with complex interaction between paramaters (when one or more paramters change the behavior of other parameter)

  3. Mike Leonzal

    Frustrating is the word: I have been a part time DJ for about 15 yrs. The intelligent lighting industry is absolutly wonderful if your a rocket sientist! Changing over to LED lights is the thing to do. In past years the old lights are mostly sound activated, at least they could function and put out a modest light show. For example I purchased a ADJ Accu spot 250 II. Cool!, but the sound activation mode is plain and simpley useless for what the light should do. Purchasing a DMX controller would be fitting. But Oh my Gosh, which controller would you use and if so how in the world would you program it for the lite hearted. In another words I don’t uderstand it for the life of me, way to complicated for the average guy! Why does this have to be so difficult for a small venue? My thought is design a simple controller with preprogramed flash cards for the unit of choice? Plug in and play – simple. Make up several types of formates and sell them. Putting on a gig is quite consuming of your time – trying to get a intelligent light fixtures to function is troubling to say the least! Make them user friendly, to complicated! CAN somebody help????

  4. Rob Sayer

    Hi Mike. I understand your frustrations. I can also say that the cheaper equipment is, the more brainache goes into making it all work. DMX tables that are inaccurate, controllers without decent manuals etc all add up to one hell of a headache. The biggest problems I see that you describe are all guys using budget equipment like DMX controllers for a few hundred dollars. Higher end professional systems use the personality files in a software version of the flash card idea you describe, making it a bit more plug and play. Cheap controllers and fixtures leave more in the hands of the inexperienced.
    Thanks for your comment.

  5. Lasse Saari

    Hi all!
    I am just making enquiries on the state of this subject at the moment, with a plan to find/make a budget 3d-visualizer for dmx-moving lights….

    I am planning to research into Blender software and see if I could use some fixtures data in there to visualize the lamps and heads. There have been rumors that a dmx-connection into Blender could be doable. Then we would have a free platform for visualizing, if we only then could get the fixtures libraries all together, preferably in xml or the like format..
    Please comment/discuss if any has any fresh info on this!

  6. Manuel Rodrigues

    I Love the idea of a standard personality file! My god what a megahuge change would this be!!! I never tought of this…!!!

    This means one showfile would work for nearly every situaltion. You can build your ideal show at the comfort of your home, show up at your venue, readres the fixtures, adjust your positions and your done!!!


    Ok, maybee you must rearange some groups and run a few macros to reprogram some things but im LOVING the idear!

  7. Manuel Rodrigues

    Ok ok,

    I realize my error of judgement. I did not read the artice carefully anough. I stil think one standard channel layout for all movers would be a great achievement in standardisation and have huge advantages! Maybee a idear for the to dig in to?

  8. Andy Macdonald

    Hi Rob,

    It’s rather a long time since you posted this, but you have some very interesting ideas on the future of personalities – and I guess have probably had one or two bad experiences that have helped form them.

    Sadly (at the risk of coming across as the bad guy here) I’m not sure that the idea of the fixture manufacturers writing standardised personalities that would work in many different consoles and visualisers could happen. I just don’t see the financial benefit to make it happen (given the only reason companies are in this industry is to make money). There is already a system in place that works well enough for most people, most of the time. What’s in it financially for the fixture manufacturers to make them want to write the personalities (and hence have the expense of employing the people to write them)?

    The DMX specification is now over 20 years old, yet there are still plenty of fixture manufacturers who fit 3 pin XLRs to their units. If they can’t get something that simple right, despite the correct one being laid down in the DMX standard, then will enough will be able generate correct personalities to be able to do away with the fixture library people at the console manufacturers? It’s not just about writing valid XML, it’s also about using the right parameter names, as Paul rightly says.


    Andy Macdonald
    Senior Project Engineer
    Carallon Ltd

  9. Michael Mackinnon

    allow me to introduce myself, i am a lowly light jock working in a small club in the UK, the rig i use consists of 4 Chauvet Qspot 575’s
    4 Qwash 575’s 4 mini-spots, 2 Ishow6B barrel scanner a strobe and two smoke machines and a laser, so quite a nice little rig, some quite nice shows are possible with this, however there is a fly in the ointment with this little lot, the Software that is used to control the rig, at the moment it is Show magic, i have used Martin Light jockey and never will again, i have tried show cad and didn’t get on with that at all and i have looked at clay paky’s hands on and a few others, i personally don’t like Desks, as i truly believe they belong on tours with bands and not in nightclubs, but that’s my own preference, to me lighting is about interpretation not about triggering sequences, i don’t personally like desks anywhere as much as a midi keyboard, most music is written on a piano keyboard so it’s logical to presume that playing a keyboard would give a better interpretation of the music.
    So the point of this post, i dont personally think that DMX is the problem, after all the fixtures have all the info hardwaired into them, DMX addressing, What uses what channels etc, at least thats my understanding of them, the problem lies in the software, now i know that there are those on here that probably use a desk and are looking at this post with humor, but those who use PC’s and software control will know exactly what im talking about, to me these programs seem to have two things in common, one is they are written by people who seem to think that LJ’s have some amazing knowledge base of DMX……we don’t, or at least i don’t, and two these programs are written by people who seem to think that LJ’s have a burning desire to learn a piece of software rather than create pretty patterns in the smoke……we don’t.
    Take martin Light-jockey, i have to say out of all the software ive used or seen MLJ is the most ridiculously complex, most unenjoyable program ever, i nearly gave up lighting after using that, show-magic is pretty much the same, so whats the solution, well there isnt one while its tied up by the major players, martin, Clay Paky, American DJ and so on, what it needs is a group of people that have skills in programming and a passion for lighting to get together and write a program, and there i hear the gasps….”Write a program?… he mad?” i know , ive heard it all before, but i do believe that it can be done.
    Lasse Saari has the right idea, using blender to create a 3d visualizer, its open source and its free and its powerful.
    Imagine the following, a program that has no fancy graphics, has no icons to work out and makes putting together a chase sequence (4 moving heads, each moving in a circle independent of each other, but all rotating round a single central point, a sequence of gobo changes could be added as well as colour changes)effortless, what is needed is the software to be designed by light jockeys, those who use lights as part of their job, people who know what works and what doesn’t, people who want to be creative and not technical, i didn’t start doing lights cause i thought learning a computer program would be fun, i started lighting because i love being creative with photons, that seems to be the last thing i can be.
    I have begun the design process into creating the ultimate software to create impressive lightshows and sequences, its called GodRays and it will be the answer you have all been waiting for.
    Planned features:
    Alters the screen depending on which hand you use most
    Uses your name when displaying messages
    Rig Design Screen will let you specify the shape and contents of your rig, no large library of fixtures, the software interrogates the Fixtures on the rig and adds the DMX patches automatically
    on the Lightshow Design Screen there will be features such as :
    Colour bump
    Gobo Bump
    Path Allign
    Tempo tap for Hats, Kick and snare drums
    Auto allign
    and a lot of other features
    A Gobo design and ordering feature
    A Gell Selection and ordering feature
    AR(Augmented reality) feature
    Light use Logging
    Stock order Screen
    and on the Live screen
    Override Flash and chase
    Visual Gobo Selection
    Colour Changes on the Fly
    Sequence Mixer
    Video Mixer
    Auto Tempo detect
    and a lot more besides
    This is what the lighting industry needs, decent software that will do what decent software is supposed to do, allow the user to be creative by having the features that we all know can be added but for some reason isnt, or at least isnt obvious.
    now i know that most on here will reply that the software they use does the job perfectly well and i suspect that this may be a knee jerk reaction from all the time spent in learning the program they use, well for all those who do think that try this little test, set up a sequence like this following example with your existing software:
    have 4 moving heads follow a straight line one behind the other, and while they are moving have them rotate, and at every 360 degrees have each one of them swap colours on the beat and change gobos on every other beat, if you can do that in less than a minute stick with what your using.
    now dont get me wrong , the existing software works, it just doesnt work in the way that makes it a joy to use, there are sequences i would love to do with my rig, but programming them is a nightmare.
    And why when searching for LJ stuff on the net, is it always labelled DJ stuff?

  10. Rob N

    I totally agree.
    I come from a music background and was involved in the inception of MIDI, an open source protocol for electronic instruments. That was defined so that, say, controller 7 is volume, so that *ANY* MIDI based instrument would recognise that channel and recognise it as volume. It is a global standard.
    If a device has special, unique qualities, these are added on the end, beyond the standard spec.
    Also one notable thing is all decent manuals, on the back page, had a MIDI checklist, so it would say “can respond to this, can’t respond to that, and these are the extra features this instrument has above the bog-standard.”
    MIDI was created in 1975 and it is still on V1.0, it works 40+ years later, everyone knows what it does and where to go. It’s about time DMX did the same.

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