[Migraine]

How I wish they could go back in time and film it in color. I can’t imagine the executive decision that put Susan Hayward’s flaming red hair into b & w.

[Seruzawa]

Color was a very expensive process back then.

[SmokingJoe]

They have developed computer technology to convert black and white films to color.
Seen plenty of black and white films/tv series converted to color.

How Are Black And White Films Colorized?

https://www.scienceabc.com/innovation/how-are-black-and-white-films-colorized.html