The projectionist has final cut, or so the saying goes, so it's surprising that more reverence isn't afforded this lowly god, this puppeteer of light, this minimum-wage illuminator. Just as with any higher power, the only time some of us even think about the presence of the projectionist is when things start to go wrong -- when the actors have their heads relegated abruptly to the bottom of the cinema screen like casualties of the woman-sawn-in-half trick, or when the image acquires a blurriness that can't be blamed on a vaselined lens. Some doubting Thomases even cast aspersions on the extent of the projectionist's skill, and ask whether he or she is really that indispensable after all -- a shocking example of impertinence and disrespect (although a former projectionist I met recently admitted he used to set up the reel before nipping outside for a pint).
Digital projection has arguably diminished the projectionist's standing even further. But June was altogether a good month for reminding ourselves that the unseen figure in the room above our heads is vital to our viewing experience. Correspondence came to light from four leading filmmakers who took it upon themselves to address in comradely tones the man or woman in whose hands their work rests ultimately. You can, after all, be one of cinema's leading visionary auteurs (and three of the four letter-writers are just that), but if the projectionist isn't on-side, you may as well have left the lens cap on.
It was always well known that Stanley Kubrick would visit cinemas where his films were playing, in order to check that the equipment was up to scratch, or that the auditorium's glossy walls were not throwing distracting reflections into the viewer's field of vision. Here  is a letter from him to projectionists sent out to accompany prints of Barry Lyndon in 1975. David Lynch had some unique advice to offer any cinemas screening Mulholland Drive -- his homely tone (beginning the letter "I understand this is an unusual request yet I do need your help" and signing off "Your friend, David Lynch") is characteristic; you can read his letter here  along with similar letters from Terrence Malick concerning his forthcoming film The Tree of Life, and, slipping to the bottom of the prestige scale in one almighty leap, Michael Bay on his third Transformers movie (though the wonder will be if anyone notices anything to do with the quality of projection amidst that picture's visual and aural cacophony).
There's also a rather good post over at CineRobot  on the subject of projectionist in movies -- Buster Keaton in Sherlock, Jr, Brad Pitt in Fight Club, Philippe Noiret in Cinema Paradiso, that sort of thing. It's a good list, to which I would add Robert Joy, getting busy in the projection booth with Madonna at the end of Desperately Seeking Susan, and the poor unnamed soul in the grim Chilean comedy Tony Manero who is beaten to death by an audience member aggrieved to find that Saturday Night Fever has been replaced by Grease. A gross overreaction, yes, but you take his point.