Is the EX1/TL500 OK for my tech-clumsy mother?

I think it would a bad idea. It was designed for those like manual controls (I own one and I think it is absolutely brilliant) . My wife sounds like your mother, about the same age, same dislike for complexity.

She currently uses a Fuji with a dual sensor (stunning low light capability) and has also used Pentax point and shoots. She was happiest with her Pentax Optio.

I found you can wrong with anything you buy as long it offers scene modes and an easy way to find them.

Good luck

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