Imo it all boils down to the Plane2 photo. If it is genuine then it points to Semyon's mystery photos being either military involvement, atmospheric electrical phenomenon or both.
Nigel, you the serious person why at you imaginations gush forth without any measure?
Already many times said that it is:
1. Too small size on a negative (a little thousand or ten-thousand - 10 in a minus of 4 or 5 degrees - an inch share).
2. It not in Simeon's films, and scraps of films of other operators.
3. Scraps not in the end, and in the middle of different films Are located it.
4. It precisely corresponds (both under the form and on the size) to loss of crystals of sulphite of sodium (Na2SO3) of that the film has been washed badly out at development.
It is necessary to know well features and to have good practice of a chemical photo (on a photosensitive film and with chemical processing in a consequence) what not to do such hasty conclusions
It I cannot already explain it to Valentine Jakimenko a lot of time in any way. He agrees with all arguments, but continues to dream on this theme. From it also there is this conversation «about planes», that «removed the falling rocket» and etc.
Could not remove it because the rocket in the end of flight flies with a speed more from 1 to 5 km a second (are some miles a second) and it does not have appreciable luminescence, even at night.
And to remove the plane at night, it in general behind an imagination side. Especially if it high-speed.
Wrt to it's veracity, i think the two smudges are very significant. Just as if two pieces of snow/sleet/graupel have hit a lens kept warm by body heat and starting to melt. I struggle with the idea that this photo is a result of say water damage.
Before to speak about the sizes «stains on lens», count the sizes with what they should be on film, and then look at physics course in section "optics" where it is told about images which are in piece, between 2 points of focus of lens.