One of the most famous UFO pictures of all time is that of Major Jesse Marcel holding the debris of the "flying saucer" that crashed at Roswell, New Mexico in 1947. Of course, he then had to retract what he said the next day and say it was only a weather balloon, but the proverbial cat was out of the bag.
UFO pictures have only grown in quantity if not quality with the advent of the digital camera and high speed sports related photography equipment. UFO pictures taken in the past have historically been grain and out of focus because they are generally blown up so much in order to make the craft visible.
With the advent of the digital video recorder, UFO pictures can be gleaned from the video footage and are stored digitally so they are much more easily enhanced. It is also much easier to spot fakes as well as digital analysis of UFO pictures can be done in great depth using techniques not available until now.
Having seen several UFO's in my life, if I had a camera at the time, I could have taken some famous UFO pictures. Alas, that was not to be. Why are they only about when I don't have my camera? It seems like somebody does not want any UFO pictures. Hmmmm