I always think its interesting that so many UFO photographs were published in the 1950's and 1960's. I used to read those books when I was young, and there was lots of "evidence".
Then the video recorder was invented. We started seeing on-the-spot film of seemingly any event that occurred anywhere. Except UFO's. Don't believe I've ever seen film of a UFO on the evening news. Kinda strange, huh?