Here’s something you can work on. I once read a book on “how to improve your eyesight”. It was a crackpot book and I knew it but I had to try. [didn’t work]
But one of the experiments was pretty neat: You imagine the blackest black you can imagine. [close your eyes, take your time]
Then when you have that in your mind, go a little darker with the black.
*That* actually improved my ‘shades of black” perception.