Corrected entry: When Nikolai's minigun if seen firing for the first time, the barrels aren't moving at all.
Corrected entry: If, as Royce notices early in the film, the sun hasn't moved, how do they end up fighting in the dark?
Correction: As you say yourself, Royce makes this observation pretty early in the film. While the sun hasn't visibly moved in the time period between their arrival on-planet and him noticing, the film continues for a considerably longer period of time after that, long enough for the sun to eventually set. The planet simply has a longer rotational period than Earth - it's not actually tide-locked.
Corrected entry: At the end when Isabelle is pinned to the tree stump by the last predator's blade that was shot at her, when she breathes it moves in time with her chest, thus showing that she is not in fact pinned as she should be, but that the blade is only connected to her uniform.
Correction: Isabelle isn't pinned to the tree. She is leaning towards the tree because she is hurt, and gets hit by the predators blade in her shoulder after shooting the predator, but there isn't anything suggesting the blade going through her shoulder and pinning her. So the blade would therefore move when she breathes, as it's only lodged in her shoulder.
Corrected entry: When Noland reveals himself he has an awesome looking weapon and armor. When the "crew" is in his hideout no one, including Noland, takes the stuff with them.
Corrected entry: Hanzo kills the second predator with his samurai, then dies himself from his wounds in battle. When this happens, his human partners are already long gone, running away towards the predators camp. They do not know about the outcome of the battle between Hanzo and the second predator, having not witnessed the battle. Later, when the third predator is killed, the two surviving humans act as if they have finally prevailed over the three predators. How could they know that the second predator is dead? More troubling, since Hanzo never shows up, they should at least be worried that the second predator might still be alive and hunting them.
Correction: They assumed, since the predator was not breathing down their necks, that the predator was either dead or mortally wounded, and that Hanzo was in the same situation since he had not shown up. Their actions of confronting the predator camp would not have changed either way. If the second predator was still alive, they'd have to deal with it after the camp.
Corrected entry: If Brody's clay-mask makes him colder, he should appear as a dark blue silhouette against the flames and not be concealed within them.
Correction: The clay doesn't make him colder, it simply hides the heat from his body allowing him to blend in with the flames around him.
Corrected entry: When Royce decapitates the last predator, the "dreadlocks" aren't cut, even tho it's a clean cut through the neck. I'm guessing it's deliberate for dramatic effect. If the "dreadlock" were cut as it would in real life, you wouldn't have the same suspense in the scene.
Correction: Several reasons why the dreadlocks aren't cut. First, they're free hanging, whereas his neck is anchored to his body. They would simply move out of the way with the motion of the slice. Second, the cut does not go all he way through the Predator's neck. Tthe weight of his head pulls it the rest of the way off. Third, we don't know what the dreadlocks are made of reall. They may very well be much tougher than the Predators' flesh.
Corrected entry: The newly formed crew begin trekking through the area and arrive at cliff where they look up to see several planets/moons. - At any point in time, they could have seen this if they looked up. A cliff would only provide a view of something below their current horizon, and should not reveal anything new above the horizon.
Correction: They were in the middle of a jungle, with lots of overhead foliage and cover. This blocks the overhead view. I live in forests and mountains. When hiking, you can't see the mountain across the valley, or the sun and clouds until you get to an open, high area, much like in the movie.
Corrected entry: It seems illogical that both clans of Predators can remote control the spaceship.
Correction: This is because of a common stroboscopic optical illusion known as the "wagon-wheel" effect; caused by temporal aliasing. The best known example of this is when the wheels of a stagecoach appear to be stationary when in fact they are rotating, because they are rotating at exactly the same speed as the camera shutter, i.e. 24 times a second.
THGhost