There’s a wonderful behind-the-scenes photograph, in black-and-white like the film itself, of a street scene from Alfonso Cuaron’s “Roma.” It’s full of lighting equipment, illuminating what look like several genuine Mexico City blocks, set-dressed to look like 1971.
It’s not real. While much of “Roma,” up for 10 Academy Awards, was filmed on real streets and sidewalks, the scene in the photograph first published by American Cinematographer magazine and then, later, the Chicago Tribune, is an illusion.
Cuaron and his designers poured cement, erected storefronts and created a life-size version of Cuaron’s memory of what the streets looked like in 1971. It was built from the ground up, in an industrial lot outside of Mexico City. Then, acting as his own cinematographer, he fussed with the lighting to get the raindrops on the cars to look a certain way, and the actors moving around the set to look another way.
And it all looks like magic.
Source : https://www.chicagotribune.com/entertainment/movies/ct-mov-oscars-changes-televised-categories-controversy-0212-story.html