Visualizers are wonderful tools that can be extremely useful to programmers and productions alike. When a show can be pre-programmed in a virtual world, countless dollars can be saved in labor, venue and equipment rental, and much more. Computer technology has allowed visualizer software applications to become very powerful and very realistic. However, there are always differences between the virtual world in the computer and the real world happening live on stage. A good programmer must understand the potential differences and how to best adapt or correct for them.
Fixture Profiles
The very concept of a visualizer requires that the application mimic actual lighting fixtures as perfectly as possible. For instance, if a programmer commands a light to zoom from narrow to wide, then the computer simulation should move the proper speed as well as correlate correctly to the associated DMX values of the actual lighting fixture. Most visualizers will get the direction of the zoom correct if they have followed the DMX map or protocol of the fixture as defined by the fixture manufacturer. However, the majority of visualizer companies do not perfectly emulate the mechanical movement times of fixture features. So if you command a fixture to zoom from narrow to wide in zero time, you may see it instantly change on your computer screen, but a real light might take 1.5 seconds to move its lenses accordingly.
The above problem with virtual fixture representation is even more complex than simply mimicking the speed of movements. Many fixtures contain effect channels that are used to trigger various fixture movements, gobo rotations, strobing, chases, internal effects, and more. Because the effect information is stored in each fixture and not based on changing DMX values, it is nearly impossible for a visualizer company to replicate these on the screen. For instance, many LED luminaires have built in effects to chase between internal zones of LEDs or effect channels used to rotate the entire fixture head. A visualizer company would have to reverse engineer the information programmed into each fixture by the fixture manufacturer in order to recreate the exact effect in the visualizer. Unfortunately the visualizer companies tend to ignore many of these effects completely and simply do nothing when the associated DMX value is received.
In an ideal situation, a programmer will have one real fixture (of each type of fixture in the plot) connected to the desk during visualization. This provides a reference to reality as you can easily see what the actual fixture is doing in comparison to the image on the screen. This practice is also beneficial when true color is essential. Due to variances of computer representation, display type and related adjustments and other factors, it is tough for an LD or programmer to be assured that the color on the screen will match the output of an actual fixture. Palettes/presets are essential when working with a visualizer so that real world values can easily be substituted for those that appeared to work in the visualizer.
Positional Representation
Visualizers are fabulous for building position palettes/presets and creating looks for a show. They allow a programmer to easily position fixtures and determine what will work best on a given stage. However, there are many factors that will affect the final output on the real stage. First, the fixture orientation is essential. Nearly every programmer who has worked on a few shows with visualization has experienced the problem where the fixtures were “hung” in the visualizer in a different orientation than the real world. When this happens, all the fixture positions will be off by 90 or 180 degrees! It can take hours to update palettes/presets, and some effects may no longer work correctly once moved to the new position.
It is essential that the fixtures on the visualizer are oriented in the same position as the real stage. Most visualizers now clearly label the position of the power cable of each fixture and this data then needs to be communicated (usually on a lighting plot) to the crew hanging the lights. In addition, the spacing and location of the fixtures needs to be considered. If the fixtures are placed on a plot in the visualizer where each fixture is exactly three feet from the next and the truss is positioned at precisely 42 feet in the air, then the actual rig needs to match as well. If, instead, the real rig is placed with fixtures at 3.2 feet apart and 41.1 feet in the air, then the focus of the lights will be incorrect. It is best to note the exact dimensional position of each fixture and trim for hanging fixtures in order to best transition from virtual to real world.
Another common mistake that can happen with a visualizer is not detailing all the elements of a production. Very often, a lighting rig will be represented in a visualizer, but not the audio, video, scenic, or venue elements. Then, when the programming is played back on the real stage, the programmer finds that lights are pointing at the back of the PA, onto the video screens or into the proscenium wall! Ideally, you should draw as much of the real equipment and venue into your visualizer to ensure that you understand what your lighting will illuminate.
The Best Tool
With so many potential differences between a virtual and a real world programming scenario, a programmer must be ready to adjust for reality long before moving to the venue. The first thing you should do is utilize palettes/presets as much as possible. Palettes/presets allow you to store a reference to values that can be easily updated later. So you can store a position or color reference that is correct in the visualizer and use this for your programming and then later simply update the palette/preset reference to the proper values for the actual, real stage. When working with a visualizer, palettes/presets should be used for the majority of your values as you never know what will be different between the computer screen and the stage. For instance, palette/presets for positions, colors, iris, zoom, gobos, gobo rotations, strobe settings, effect movements, prisms and anything else that you select and adjust in a light will be beneficial for a quick and smooth transition.
Create a Reference
Another trick is to create a specific position palette/preset that will help you understand how well the visualizer image and the real world are aligned. Typically, all fixtures are placed in a down center stage position in as tight a zoom or iris setting as possible. If you align the output of each perfectly in the visualizer, then you can refer to this position first thing when you get to the real stage. It will become instantly apparent how correct or incorrect your real world fixture placement compares to that of your visualizer. It may not help you update all your other positions, but it will help you to determine if a truss is too low or perhaps if a few fixtures could be easily moved as opposed to updating lots of positions.
Furthermore, this same trick can be used in reverse should you wish to continue to view the visualizer after you have corrected your positions for the real world. Once you correct the palette/presets for your real stage, then these same values may no longer work correctly on your visualizer. This is because of the difference in actual positioning of fixtures in the virtual verses actual stage. After you update for the real world, simply place your fixtures in the down center stage position and now move the actual placement of the fixtures in the visualizer (not the DMX values) until the beams align correctly in the center of the stage. Now your visualizer will be better aligned with the physical placement on stage.
Get Real!
Programming with visualizer is a great experience, but programmers need to be prepared for the difference between the virtual and real worlds. Although the actual programming process is no different, there are many things that must be considered, such as fixture profiles and positional variances. Be sure to make extensive use of palettes/presets and their ability to easily update values. With a bit of practice, you can easily transition out of the virtual and into reality.
