In these recent years there has been an increased interaction of visualizers within the lighting field. More advanced they get by time, more realistic they've simulate. Some of the popular visualizers nowadays includes Esp-vision, martin show designer, wysiwyg, capture & lightconverse.
Now they can render realtime shadow, laser, pyrotechnics, moving objects, colour temperature as well as direct visua medial output. You can really run 80% of the show from a visualizer.
One of the major reasons with using a visualizer is that it can save a really huge amount of budget. By saving a few days of total power usage for the site for pre-production and programming is more than enough for a day or two to hook up in a lighting visualization studio.
And now there's console with build-in visualizer which you just have to load the project show file into the console. So far I've roughly stated the advantages of using a visualizer. The problem is that the more powerful the visualizer, the more powerful computer you would need to run it. With endlessly upgrading your computer is another thing to consider.
I'm sure lighting designers and programmers do a lot of planning and designing for a show. With the latest technology, there's really not much to worry about. You can still think of a realistic view even while working virtually on your computer. But for designers from the time where there were no visualizer technology, they worked virtually while designing realistically on the site. Therefore, there is a major difference between designers or programmers from the past and present.
Experienced programmers had virtually run the lights in their mind. And are able to foresee the results. By relying mostly on a visualizer, the initial visual of design will be different for the people who work with visualizers all the time. For instance, if the show's major colour is a strong congo, but in the end you just find out that the fixture can't generate such strong congo colour because of the colour mixture wheel does not hold the latest technology.
One of the major things I've found is that by time, some fixtures with older technology or fixtures which are faulty such as bigger gobo wheel gaps, colour mixture leakage or strobe, speed intensity tends to spill. The reason for a visualizer is to simulate reality and to give a 3-D view to a person's idea. I wonder will this faulty implant into the software too.
Always remember to foresee the realistic result and the virtual result. You must at least have really use the fixtures before and test it thoroughly or at least have the photometric chart. Know the good or bad results of colour mix, brightness, speed for all kinds of weather conditions. It's best to test the fixtures before hand if you propose to use it on a show with a visualizer render image.