Until earlier today the Twitter account @555µHz was tweeting, as far as any of us can tell, the entirety of the 1986 motion picture Top Gun, one image at a time.
The account's name was 555 microhertz. The unit hertz represents "cycles per second." Five hundred and fifty-five microhertz is one cycle every 1,800 seconds. The account was posting an image—from what I can figure, one for every second of the movie—every 1,800 seconds.
If you refreshed the page every 30 minutes you'd see a new image. For now let's fudge and call that its refresh rate: 555 µHz.
Top Gun was filmed on 35mm film stock in a camera taking 24 still images every second. Modern 35mm film projectors operate at double or triple this standard frame rate: Either 48 or 72 Hz. For the sake of convenient comparison, we'll call this the projector's "refresh rate." In this case the figure refers to the number of times every second the projector's shutter is released, blocking and then allowing light to project an image on the screen. If you watch Top Gun in one of the country's remaining 35mm projection houses (you can purchase reels here, for $699), you will see ("see") 48 or 72 images a second—each individual frame will flash two or three times before moving to the next.
By contrast, the screen on which you're reading this post likely has a refresh rate of 60 Hz, the standard for liquid crystal displays of the kind you'll find in your phone or attached to your computer. Most LCD screens serve up a new ("new") image 60 times a second; some refresh at 120 Hz or higher. Digital projectors, which you'll encounter in most theaters in the U.S. these days, have similar refresh rates.
If you play Top Gun on your 120 Hz LCD display, then, the screen will "paint" a new image 120 times a second—that is, five times for every frame of the movie. Some LCD screens will attempt to compensate for the difference between the screen's refresh rate and the movie's frame rate through motion interpolation, in which the display creates new intermediate frames threaded between those that were actually photographed. Thus a film like Top Gun, filmed at 24 frames per second, appears on a screen with motion interpolation turned on as though it were filmed at 60 frames per second—the rate at which soap operas are filmed.
(Our vision is shockingly well-trained to discern quality of motion. Twenty-four frames a second, the rate at which nearly every Hollywood movie we've ever seen has been filmed, registers immediately as professional and expensive. Six extra images every second and the movie looks like a cheap home video. Motion-interpolated to 60 fps, Top Gun suddenly looks like Days of Our Lives. In some cases we might say the motion looks "unnatural," or, on the other hand, "too real.")
For one second of Top Gun in a movie theater, we have 24 individual still images, each presented two or three times. On a modern television or computer monitor, those 24 stills are presented to us five times each; we might even have 60 individual still images, only 24 of which are actual photographic captures, each presented twice.
On Twitter, for one second of Top Gun, we had one image, presented once, every thirty minutes. 555 µHz.
We watch movies weirdly now, or maybe we always did.
The business of refresh rates on consumer displays is thorny. It's the kind of thing to which extremely long and contentious threads on online forums are devoted. It's thorny because the business of human vision is thorny. Your brain doesn't perceive motion in terms of series of single images, though series of single images can appear as motion to the eye. For reasons that are complicated and not entirely agreed upon, human brains will perceive as continuous motion still images presented in sequence above a certain speed—somewhere around 16 Hz, we'll say.
This illusion, the principle on which the entire affair rests, can make some film theory almost metaphysical. The process of projecting feels metaphysical, at any rate, or mystical: Some occult mixture of light and time, some magic number of cycles per second. An infinite gap between object and image. Film itself is independent of time, but projected films aren't. Projectors refresh, but celluloid doesn't. Film has no refresh rate. Neither does human vision.
The scent of poetry that surrounds the tools and processes of filmmaking makes it easy to mourn the death of film as an object. Who can limn the metaphysics of motion pictures, or whatever, when every step is a reduced to a new collection of 1s and 0s inside a closed box? But things that are more complicated are rarely less interesting. Refresh rates at levels beyond human perception are transcendent in their own way. Motion interpolation presents a new set of problems, which is the same as saying it presents a new set of ideas.
There are new opportunities, too. @555µHz is—was—the first movie projector on Twitter, undertaking a screening of Top Gun, at a refresh rate running counter to every trend in display technology and our understanding of human vision, not even a refresh rate but an accumulation rate, a projection that turns itself into a film strip, itself being projected by and on your screen.
Originally I'd planned on embedding several of the tweets throughout the this post, but earlier today, following a takedown request from Paramount Pictures, which owns the copyright to Top Gun, Twitter suspended @555µHz. Twitter has not responded to requests for comment; like most companies operating under "safe harbor" laws it likely automatically suspends accounts that are subject to takedown request from powerful rights-holders.
Precedent isn't settled on this but it's largely accepted, or taken for granted, that screen grabs don't infringe on copyright. But @555µHz isn't just a collection of screen grabs. It's an unauthorized public performance. Its success demands that it be removed.