Your post and this sentence:
In these cases, real people were used to paint them as models.
...reminds me of a movie I watched at the cinema at the end of December. An artist who painted saints and scenes from the Bible but the models were people who were marginalized in the society. He also tried to catch and show the sorrows and real pain in the expressions
Exactly, people were used to show that suffering and pain so that it seemed as real as possible.
Thank you very much @mipiano!❤️