I highly recommend the movie "Tim's Vermeer" about the likelihood that Vermeer used something like a lightbox to paint his paintings. Specifically, his ability to reproduce light and color is unmatched while he only had basic training as a painter and never let anyone see him work. A fascinating engineering problem to deduce how he might have accomplished this.
I'll note two parts of the movie that support my view. First, if his art is so great, then why is it not displayed all over the place? He has a few alleged experts giving praise without criticism, and in the end, it is on the wall in his bedroom. Surely, if the art were that easy to recreate, galleries would be demanding his piece?
Second, notice how they never actually show the real painting. In fact, at one point they make it out to be a conspiracy, that the painting is being kept in some back room nobody can access. I would loved to have seen the real painting side-by-side with Tim's alleged reproduction. I suspect they didn't push to hard for access, because it would have ruined their narrative.