A digital projector keeps a log of every playback: the film's title, the start, the end, and the key that unlocked it, because the studios audit those logs to bill us. Screen 3 shows a screening most nights at three, of a title we do not hold, on a key the server says it never received, and the lamp counter goes up by the length of the film.
I am the chief projectionist for a four screen independent, which in practice means I am the IT department.
How a screening works now.
The film arrives as an encrypted package on a hard drive. It goes onto a server in each screen. A key comes separately by email, tied to that projector's serial number, with a validity window: this film, on this machine, from Friday at noon to Thursday at midnight. Outside the window the projector will not decrypt a frame.
Everything that plays is logged. Title, start time, end time, key used, projector serial. The distributors pull those logs and bill us on them, and a discrepancy between the log and the box office is a conversation nobody wants.
The projector also counts its lamp hours, because the lamp is a consumable that costs four figures and is changed on hours.
Screen 3's log shows a screening most nights, starting between ten to three and ten past, running about ninety eight minutes.
The building is locked at that hour. The alarm is set. Nobody is in it.
The title in the log is not one we hold, or have held, or that I can find in any distributor's catalogue. It is a title. It is not a real title.
The key referenced in the log is not on the server. The server keeps every key it has ever received, expired or not, and it has never received that one.
The lamp hours go up by an hour and thirty eight minutes.
That last one is the reason this is not a software fault, and I want to set it out properly.
The lamp counter is not a line in a log. It is a hardware counter tied to the lamp power supply. It advances when current flows through the lamp, and it is the number I change lamps on, and I have changed a lot of lamps, and it has never once been wrong.
An hour and thirty eight minutes of lamp, in a dark auditorium, at three in the morning, on a title that does not exist, from a key that was never delivered.
What has been done.
The server was reimaged in 2022. The projector was replaced, under warranty, in 2023 after I raised it with the manufacturer. The new projector has a different serial number, which means every key we hold had to be reissued, which was a week of work.
It logged a screening on its fourth night.
The manufacturer's engineer looked at the logs remotely and told me, in writing, that the playback log entries are consistent with a normal playback and that the lamp hours are consistent with the log, and asked whether I was sure the building was unoccupied.
The auditorium has a camera because of the licence, and the camera records on motion. It records nothing between one and five. The screen in those clips is dark.
What the lamp does that the camera cannot see.
A projector lamp is an arc lamp and it is hot, and the projector has a temperature log because the lamp house is cooled by fans and overheating kills the lamp.
The lamp house temperature at three in the morning on those nights rises the way it rises during a screening, holds for an hour and a half, and falls.
So the lamp is lit. Something is being projected. The camera in the room shows a dark screen. The camera is a camera and I have no reason to think it is lying, and I have stood in that auditorium at three in the morning, once, and the screen was dark and the projector was warm.
What is done about it.
I zero it out of the distributor reports, because there is no film to report and no distributor to report it to.
The lamp hours are real and they cost money: an extra hour and a half a night is a lamp change about every eight months instead of every year, and I have put that in the budget as increased usage, and the owner signed it.
What I do.
I run the screens. I build the playlists, I ingest the drives, I load the keys.
The one thing I have changed is where I stand at three.
I used to do the overnight ingest from the projection booth, because it is quiet and the servers are there and it has to be done before the first show.
I do it from the office now, over the network, which is slower and just as good.
The reason is the once. Screen 3's booth has a porthole onto the auditorium, and at three in the morning in November 2022 I was at the server with the lamp lit behind me, and I looked through the porthole at a dark screen, and then I looked down at the auditorium, which the porthole also shows, and the seats had people in them.
Not the camera's people. The camera showed an empty room and I checked it the next day, twice. Through the glass there were perhaps forty of them, in the middle rows, sitting the way people sit in a cinema, facing a screen with nothing on it, lit from behind by a projector showing a film I could not see.