- In compressed audio file (such as MP3)
- In signal processing chains in the studio (process mid and side channels separately, then convert back to L/R)
- In certain stereo microphone recording techniques (there is a type of microphone which records left and right, but with opposite phase)
> left and right, but with opposite phase
The classic mid-side mic technique uses two capsules. The first (middle) is a cardioid or omnidirectionsl facing the subject, the latter (side) is a figure-8 turned 90 degrees. The capsules should be as close to each other as possible to avoid low-frequency phase errors. The signals are converted to L+R via a simple Mid/Side network:
L = 0.707 * (M+S), R = 0.707 * (M-S)
which is where "opposite phase" comes into play.
Kids being kids are going to try really hard to get them to go off the rails.
Nope:
Visual artists are very fashion driven. As technology creates new possibilities, they get abused.
In the 80/90s music videos had fade/dissolve effects. Then in early 2000s a lot of them played with the aspect ratio "black bands" (like when you play 4:3 on 16:10), making them white, pink, or textured, with border lines and other effects.
In 2010s slow-motion (high FPS played back at regular speed) was the thing. So every other video had the slow motion "water/colored dust hitting something" scene.
Since 2015, color grading is the new fad. Also unnatural weird (LED) lighting, like the left half of the frame in strong red light and the right half in strong blue light.
Color grading is also infecting instagram. For example in city photography, there is quite a trend of grading them orange/teal.
There is also a lot of social pressure to color grade. If you don't, fellow artists will say something like "look at that peasant, he didn't grade his stuff, what a noob, putting out real colors, he probably doesn't even know what a LUT is".
And then you have the honest noob who tries to improve his skill, and he sees all the pros doing it, so he concludes that he should too, since all the pros can't be wrong, even if to his eyes the strongly color graded video kind of looks like shit, but he's just probably wrong and just needs to educate his aesthetics.
There will come a point when color grading will fell out of fashion, just like you rarely see a fade/dissolve or slow-motion effect today, and when they are used it's because they make sense, not because you must do it no matter what.
As for the NSA angle, this location was not on the list published by the Intercept in 2018.[1]
[1] https://theintercept.com/2018/06/25/att-internet-nsa-spy-hub...