I stumbled upon this ability by accident;, I can look at historical photographs and instantly see things that are extremely unusual that everyone else misses. The first time that this happened was with the JFK assassination photo set. I had never seen them before. Nor do I have any opinion on what happened. But instantly I saw things that would get me certified as a crazy person so I didn't tell anyone. What I saw was so clear to me that I Googled and was amazed that nobody else had ever seen what I saw.
This is a totally undeveloped ability; I have never been trained to do it. I would like to train myself in it but have no idea how. Maybe I should get a mountain of famous historical events like photos from WW2 and see if anything happens? I add that I haven't watched the Farsight JFK movies yet.