Gemini

I Gave Free Gemini Three Public-Domain Black-and-White Photographs to Colorize. Two Came Back in Colour, One Was Refused Twice, and Both Successes Arrived With a Watermark and a Quarter of the Pixels.

Same prompt, same free account, three old photographs. Einstein at his blackboard and the Hindenburg burning came back colorized and convincing. Dorothea Lange's Migrant Mother came back with 'I don't seem to have access to that content', twice, with the chat auto-titled Colorization Request Denied. Both successful files carry a Gemini sparkle in the bottom right corner, and a 2523 by 3313 original returned as 896 by 1177.