Something I figured out that was handy for guessing some human pieces was trying to figure out what the prompt would have been for generating the image. If I couldn’t formulate with words what the image was, then it was more likely a human artist.
On the other hand, looking at light, shadow, and reflections to see if everything made sense really didn’t help.
The fraction of people who mess this up is too high. The common denominator between them is they confuse 100% and 100