Here are a couple attempts trying to solve an NYT hard sudoku puzzle: https://ibb.co/gtJghBP https://ibb.co/9nvHT1P

1) The half transparent green font color is really hard to read over a white background.

2) It fails to recongize already filled in squares and tries to change them. The source is computer generated and the image is pretty clear. It seems like a best case scenario for digit recongnition, nevertheless it fails.

3) It constantly re-evaluates while I'm trying to hold the puzzle up to the camera with varying degrees of success. Too fast for me to get a screen grab when I see a successful attempt among all the failures.

Cool project though! I was excited to try it :)