I found a link to a analysis performed on the print itself, looking for any evidence of manipulation.
Source:
Source: https://drive.google.com/file/d/1tWMZ232qgDE6Tru7jwgG-nsqoeQZpIm3/view
I agree with the analysis. It does look like a genuine photo of a real object taken in one shot. The greyscale Range of the object is close to that of the plane.
I am looking for horizontal blur. This would happen if the photographer tried to follow the plane. A skilled photographer would do that, to get a sharp picture of the plane. Looking at the poles in the bottom, it looks like a little blur. But not the trees.
The ufo looks like the most stable object and this is a little suspicious, but it is really not possible to say for sure.
I think the UFO is fake and somehow put in the picture afterwards in the post production. You can put an object onto the photo paper, do a lets say 50% exposure, remove the object and do another 50%.
The object also looks mirrored in the "artifacts", the light and dark spots. That is also a clue.
Will get back on this.
Full color printing simply uses 4 half-tone screens, one each for cyan, magenta, yellow, and black; and since the picture is b/w anyway, that's pretty much exactly what it would have looked like, possibly bigger and with a finer grid, but still the quality of the photographic paper used for the "poster" would be leagues above the quality of the news-printed reproduction.
Take a magnifying glass and look at a newspaper if you don't believe me.
Correct. I have worked in the printing business and also developed film and prints in darkroom at home and work. To print a photo on paper, newspaper og posters, you use "raster". Basically dots in different sizes on transparent films. One film for each color, Cyan, Magenta, Yellow and Black (for better contrast in the dark areas, since CMY only produces a dark brown color. Reason is the "offset" print technology can only either put ink or no ink on the paper. No greyscales. The different sizes of raster dots, makes the grey-/color scale. It's actually a optical illusion. The dots a small and unnoticeable when viewing from a distance, lets say 30 cm, reading a book og newspaper.
The dots are transferred from the film to a offset printing plate witch then transfers the ink to the paper.
Low quality paper like newspapers and books smear out the printing ink, so you would use bigger raster sizes to avoid the big raster dots that covers 90% of the are smear out and covers 100% = not dark grey but black.
On the other hand you can use finer raster dots on high quality paper for magazines.
The viewing distance also plays a role. A big wall poster is normally viewed from a bigger distance like meters and not centimeters. Then you can use much bigger raster dots.
But there is much more to the story about image quality.
Any film used in analog camera (like 35 mm Ilford XP1 400 in this case) produces the color or grey scale with fine grains of metallic silver. They get dark when exposed and developed. But in a analog way. More light = darker color/grey. The grains are randomly distributed but has a somewhat fixed size. ISO refers to the grain size. Bigger ISO (like 400 vs 100) mean bigger grains. Bigger grains needs less light and therefore you would use bigger ISO number in lower light conditions. Downside is it looks more noisy, because you can begin to see the grains visually.
But there is more... the photographic paper also has grains.
The apparatus used for transfer negative film to photographic paper also as lenses and needs to be in focus.
The camera lens plays a big role in image sharpness too.
... so you can imagine the quality loss for each many processes before you have a picture on paper, if you are not very careful and skilled.
Today you can scan the negatives and get GREAT results form old films. The XP1 400 produces very sharp images with the right camera lens.
This UFO picture is very bad quality. It's very unsharp. It could easily be a photo of a photo of a photo. Is that the case is difficult or maybe impossible to say. But could it be done and produce a picture like this, sure.
You can google "newspaper raster", "ILFORD XP1 400 pictures" etc to see examples of offset print and the quality of the film.