Kubrick's background in photojournalism seems to have influenced his lighting setups as well. Generally the lighting in his films comes from within the shot, which adds to the feeling that the camera has penetrated a private world. Where most narrative filmmakers use lighting to subtly steer the audience's attention, Kubrick granted unusually wide autonomy to the diegetic space. And so you watch the films in a heightened state of attention, since you always half-expect someone to enter from offscreen. Consider this shot from one of the dialogues between Peter Sellers's sensible Group Captain Lionel Mandrake and Sterling Hayden's psychopathic General Jack D. Ripper:
Note how the brightest light comes from the bathroom on the far right side of the frame. The further you get to the left, where Mandrake sits, the darker and grainier the image appears—there isn't as much light on that side of the room, and Kubrick hasn't added any artificially. This setup would seem to run counter to the dramatic content of the scene, which illustrates that Ripper is a "dark" force and that Mandrake must oppose him. A more traditional filmmaker would likely cast a subtle halo effect on Mandrake and put Ripper in shadow. Taking the opposite approach, Kubrick hints at something more sinister—that the distribution of "light" and "dark" forces in the world does not conform to any pattern we know.
Now consider this shot of Mandrake in the control room of his air force base:
Here most of the lighting comes from overhead florescent bulbs—many of them to the rear of the principal action. This has the effect of deemphasizing Mandrake's significance within the world of the film, despite the fact that he occupies a front and (almost) center position in the particular shot. It also underscores Dr. Strangelove's central irony—that in creating systems that can function independent of human interference, humankind has in fact hastened its own annihilation.