I've had the good fortune to see at least two sides for several industries.
When I was young, I worked as a stage hand and projectionist. While the theater I worked at, Harvey Auditorium in Bakersfield, was probably one of the most capable theaters around, putting theaters like San Jose's Performing Arts Theater to shame even today, it used 30's and 40's technology. The light board used "Hystersets" or thyratron tubes to control light dimming circuits. We could run 32 circuits with 6 scenes and each scene having 3 preset intensities. It was a live stage meaning amplified sound wasn't needed but we did have it. We also had a pipe organ.
I worked shows, like the Ice-Capades at the Bakersfield Civic Auditorium, as well. I ran a follow spot, the bright light that follows performers around. They had a director that called the light changes, who each of the 12 spot lights was to follow and what color, etc. Their audio was two synchronized reel to reel tape players so that if one failed they could switch to the other, and continue with out interruption.
When I was a projectionist, the 35mm films came on 20 minute reels of film. The projectionist had to change from one projector to another, as needed during the film, to show the 4-6 reels for a typical movie. The sound was optical on the film. The lamps for the projectors were carbon arc, like welding rods. Now the projectors run the film from platters that contain the entire film, no changeovers necessary. Audio now is multi-track magnetic. Lamps are Xenon providing light at the touch of a button rather than having to strike the arc and adjust the gap and focal point of the arc. Digital projectors are around as well, eliminating the film.
I've had the good fortune to work at television stations in the days of black and white images and live shows. We recorded on 2 inch quad tape drives, now the signal is digital on optical and hard drives. We did 2.5 hours of live shows every night. We also had the only regularly scheduled stereo simulcast music show. Now nothing is live, even a live show has a delay and stereo TV is the norm, you can even choose a language.
I worked in telemetry ground stations in the near infancy of satellite systems using fm, fm/fm and pcm modulated telemetry signals, ocilliographic recorders and high speed tape drives. Now, your home computer is more powerful than the telemetry ground station I worked in.
And I worked with traffic signal control systems when they filled a good sized closet and had hundreds of relays and analog timers. Now the cabinet is a quarter the size and the capabilities hundreds of times better. (I'm not sure traffic runs any smoother ,though)
I've worked with computer systems from their near infancy to now seeing vast changes. I worked with computer systems that filled a room, had lots of tape drives as big as a refrigerator and weren't as powerful as a calculator today. One of the computers I worked with had a whopping 4k of magnetic core memory. This computer controlled all your military's satellites. My first personal computer had 4k RAM, ran at 1mhz and was one of the most powerful around. My current personal computer has 512 Meg Ram and runs at 3 ghz.
Any way, back to the point, it's been a while since I worked on the stage, worked in television, worked in aerospace, and now even my most recent experience with advanced traffic control systems is becoming obsolete, quickly.
Watching the show here at the Rio and checking the web for information about the show, I came across an article about how the show is run. It brings home the point of how much things are changing but also how much they are integrating.
The show here at the Rio could probably run with no stage hands except those that move props. Spot lights now use pan tilt zoom controls, lamps are LED, and everything is computer controlled. In the case of this show, all these computerized lights, audio, video, overhead trolleys, etc, are running independently but synchronized by a SMTPE time signal. Video and audio are integrated into the show and are digital. The show runs like clockwork, perfectly every time. It must take some of the fun out of doing the show for the talent and the technicians, but it's perfect every time all the same.
When I worked on shows, they were never the same twice and that was part of the fun.
All this technology has come together in a show like this. Time synchronization like on space systems, video, audio, computers. Wow. I'm really impressed.
And, oh yeah, the girls are cute too!!