Just saw it last night.
The entire thing is from the POV of a camera, which I think the makers used very well, in terms both of special effects and characterization. Outside of a few very minor CG effects issues (Catching the baseball comes to mind), it felt very real, like the whole thing actually happened. Characters, situation, everything.
All in all? Great movie. I totally recommend it.
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There never was a post. Swamp gas from a weather balloon was trapped in a thermal pocket and refracted the light from Venus.