That's a great question that allows us to address some interesting aspects of the phenomenon:How many people had photographic gear at hands when they saw something UFO-like in the sky in the 1960-s? Or movie (8 mm) cameras? Very few is my guess. But nevertheless we see quite a number of UFO documentaries - images and movies. Now every person living has at least one gear that can make photographs and videos. Some have more that one item, some have 3D od 360 degrees cameras. So we are to expect the same growth of UFO documents - still and moving images. But so far I don't see such an increase. Why so?
Yup. Just from today:The militaries have good pictures, and many pictures have been confiscated too, as well as films and other evidence. As our nuclear arsenals have developed and we continue to destroy the planet, activity is centered on the military, e.g., Nimitz, nukes, etc. And they certainly have pics and films, radar of all of that; it is the goal of that mode of interaction, while maintaining contact with the civilian population.