system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When shows/movies that were in black and white are remastered in color, how do they know what everything actually looked like?

Is the color correction accurate? Or is it just best guess? How do they also go about making a best guess?
gpt
> How do they know what everything actually looked like?

That isn't the object of the game.

Black and white directors knew their movies would come out in black and white, so they filmed the movie accordingly.  They knew they had to use contrast rather than color to make the movie visually interesting.  They knew it didn't matter if an actor's brown shoes clashed with their black slacks.  In *Psycho*, Alfred Hitchcock famously used chocolate syrup to simulate blood, because he knew he could pull it off.  Recreating the colors a black and white movie was filmed with could very well wind up with a very crappy looking color movie.

So in a lot of ways they original colors don't matter, what you want to is make a black and white movie look like a color movie.  Sure, you want to make sure the sky is blue and the grass is green and Rita Hayworth's hair is red, but after that, mostly you want to make a good looking movie.