I was trying to see if they looked like jets or birds or rotating saucers.
The initial explanation wasn’t that they were the full images of jets, it was that they were reflections off the jets, and if you’ve ever seen a reflection on an aircraft before you would know the shape of the reflection is nothing like the shape of the aircraft, so you might just see a bright spot in the reflection and wouldn’t necessarily see any wings.
This reflection explanation seems to fit how the objects vanish, because as the angle of the reflection changes so can the intensity…I’ve seen this before myself, once when I thought I was seeing a UFO, which actually turned out to be an airplane reflection, which looked absolutely nothing like an airplane until the angle changed enough so the reflection vanished, similar to the way the UFOs in that video vanish.
The photographer might not have known they were jets, but they move exactly like jets would move and at the same estimated speed of the jets, which was unusual at that time because jets were new back then and people weren’t used to seeing aircraft move as fast as jets. The Air Forces initial investigation concluded they were probably the two jets known to be flying in the area at the time.
At Wright-Patterson AFB the film was briefly examined and determined to be the reflections from two F-94 jet fighters that were known to be flying over Great Falls at the time of Mariana’s sighting. Lt. Col. Ray W. Taylor returned the film to Mariana with a cover letter stating that “our photoanalysts were unable to find anything identifiable of an unusual nature”. However, according to Air Force officer Edward J. Ruppelt, who would become the supervisor of the Air Force’s Project Blue Book investigation into the UFO mystery in 1951, “in 1950 there was no interest [by the Air Force] in the UFO, so after a quick viewing, Project Grudge had written them off as the reflections from two F-94 jet fighters that were in the area”.
The later so-called “debunkings” of the jets explanation are dubious at best and some of them even admit that they don’t really rule out the jets explanation.