Imagine, if you will, that instead of reading this garbage, you're enjoying an exciting night out at the theatre. You take your seat and, after a few minutes, the curtain rises – but something's wrong. The actors look decidedly squat. Stretched out horizontally. Their faces smeared to almost double their usual width.

Come to think of it, the set also looks wrong – as if it's reflected in a funhouse mirror. The whole thing makes you feel nauseous and slightly drunk. You look at your hand, which appears normal, then back at the stage – which still looks strange. You glance around the auditorium in distress, only to discover your fellow audience members – also normal – don't even appear to have noticed. They're all happily following the on-stage action, apparently oblivious to the bizarre optical illusion taking place before their very eyes.

Confused, you stumble out into the lobby where, as luck would have it, you bump into an usher. You explain what's wrong and beg him to help. But he merely shrugs and asks: "Does it matter?"

Obviously, that's a mad scenario. But that's the sort of thing that happens in cinemas these days, when there's only one projectionist looking after umpteen screens. The encounter with the usher actually happened to someone I know. And to answer the usher's question: yes, it does matter. Because if your cinema can't be bothered to show films properly, we might as well stay home and watch dogs blowing off on YouTube. The image might be blocky, but there's less chance of catching listeria from a hotdog while watching it. And, with any luck, it'll have been uploaded in the correct aspect ratio.

Did I say "aspect ratio"? Yes I did. And if you don't have a clue what I'm talking about, there's a very good chance your television at home is set to the wrong aspect ratio, in which case I'd like you to stop reading right now and punch yourself hard in the kidneys.

There are only two kinds of people in this world: those who don't have any problem with watching things that are randomly stretched or squashed, and decent human beings who still have standards. Seriously, anyone who wilfully spends hours basking in front of a TV upon which every scene, every object, every face is monstrously distorted clearly has such a slovenly lack of self-respect, I'd be surprised if they bother to wipe after going to the toilet – assuming they still use a toilet, that is. To be honest, they probably just go right there on the sofa. What's wrong with you people? Why have you given up?

You may say I'm a pedant – but I'm not the only one. I hope some day you'll join us, and the world will live as one. Please note, however, that my vision of global harmony is presented in a 16:9 aspect ratio. And if you don't know what that means, you'd better find out quickly, before the stormtroopers come for you. Hurry. They're peering through your letterbox right now.

That last line was an aspect ratio joke you're not geeky enough to get. See how you're missing out?

"Still, if you choose to punish your own eyeballs in your own home with your own incorrectly-adjusted television, at least you're only hurting yourself, whereas cinemas which lazily fart films at the screen without checking they're even the right way up are displaying naked contempt for a roomful of innocent strangers paying for the privilege. Years ago I saw the film Downfall at a local multiplex. During the final act, the picture suddenly went out of whack, so Hitler's forehead was at the bottom of the screen and his moustache was at the top. Turns out it's hard to take Hitler seriously when that's happening. After a few minutes of this, people started calling for the projectionist to sort it out. But nothing happened. After 10 minutes, someone went to get the manager. After about 20 minutes, the problem was sorted out – at a guess, because the reel changed automatically. When the film ended and the credits rolled (miraculously, the right way up the screen), I tried to complain to the manager, only to find myself talking to an oppressed ticket-ripper, who explained, wearily, that despite having about 12 auditoriums, they only had one projectionist, who had to run between screens like a man spinning plates. "Why don't you hire more projectionists?" I asked. He just looked at me, trapped and helpless, as another paying customer came over to complain. If you ask me, every screen should have its own projectionist, as well as an usherette, an organist, a conductor, and a sniper trained to blow the heads off anyone who dares open their mouth after the titles start.

That was about six years ago. Today if you go to the cinema, you're slightly less likely to be subjected to that kind of error if they're using a digital projector, in which case there's probably no projectionist at all, just some kind of iPad app flickering in the darkness. Fortunately, there's a chance the film will still be ruined by your fellow audience members, who will loudly field phone calls throughout, because they're selfish dunces with no concentration span, reared in a modern world with no respect for the correct way of approaching any piece of filmed work, even if it's Transformers 3, which is this: either watch it properly, in the correct aspect ratio and in absolute silence, or get out of the room and go home, where a galaxy of smudgy, 28-second YouTube videos awaits you with cold, open arms.