I could be extrapolating, but the use of these darker, more sombre shots (using chiaroscuro, which is arty speak for the use of contrast between dark and light) could be a knee-jerk marketing reaction to fan reservations about the film’s retro look. Fans’ responses to the first shots from the film were mixed, with many die hard Trekkers expecting a darker feel rather than the saturated primary colours that were ultimately revealed. That said, the four Comic-Con posters that arrived this summer were similarly glowering (though rather less monochrome) affairs so I may be reading far too much into this.