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Was gonna register anyway sometime soon, cause i'm just starting modding GTA V and looking into making machinimas. But you guys talking about "filters" made me do it now, Movies and Tv shows dont use filters anymore, they use a digital process called color grading. Where a filter would grade all colors in a scene towards that one color. Color grading picks one prevalent color in a scene, grades it towards a certain color. And then grades all colors contrasting that color (whether it be by light/dark, foreground/background, ground/sky or so) towards the color that is exactly opposite on the color wheel. This to create a contrast that unconsciously (or rather, once you know this, consciously lol) grabs your attention. Sadly in 95% of the cases this leads to mainly oranges and blues being used.
For those who want to read up a bit more here: http://priceonomics.com/why-every-movie-looks-sort-of-orange-and-blue/
This one goes goes a bit more in-depth: http://theabyssgazes.blogspot.nl/2010/03/teal-and-orange-hollywood-please-stop.html
@Think_Tank in those kind of shader injectors you can indeed modify RGB curves. (color grading)