A week or two ago, I sent a tweet to @imaxbirmingham on Twitter and asked if I could have a tour of the projection room. I’ve only ever seen projection rooms by looking through the window, and I’ve never seen an IMAX projector in person, so I thought it was worth a go to ask – and it was! The next day, I got an email from their PR manager, Caroline, asking if I’d like to go along one day and see it, as a special once-off treat. So, yesterday (30th Jan), I went along to Birmingham with my dad (he expressed an interest in coming along), and met up with Caroline’s colleague, Sally, who gave us a tour.
So, up we went in the escalator to the 5th floor, which is the upper part of the IMAX theatre, normally off limits to normal visitors. The 4th floor is where you usually exit the theatre, and the 5th is all the behind the scenes stuff. Walking out the escalator, there was a small hand-operated forklift (for lifting the film reels), about 50 boxes of the Harry Potter film, and a few large metal cases with film reels in them. Quick explanation: when they get the film, it’s in boxes, so it has to be manually spliced together into one long film. Anyway, moving on, down the hall we went, and into the projection room!
So, the projection room. First and foremost is the huge IMAX projector – it’s MUCH larger than a 35mm projector, and along with the film reels behind it, it takes up a lot of room, as you can see:
The projector itself is pretty much the same basic idea as any other projector, just bigger. The first thing you notice are the pipes coming out the back of it – the big one is for air cooling, the smaller ones are for water cooling, mainly for the £3,500 Xenon bulb (which, while we’re at it, only lasts 900 hours, which isn’t much compared to, say, my home projector). In fact, the cooling is so critical that there’s a pump room next to the projection room, which has backup pumps if needed, and uses its own dedicated water supply from (I presume) the council. The air also has another role – somehow, through some fancy complicated method, it uses compressed air to keep the film rock solid steady. If you go to and IMAX flick yourself, doubtless you’ll notice that. Compared to normal cinemas, it pretty much doesn’t move at all. Impressive stuff.
Next, obviously, is the 70mm film. Since Avatar 3D was about to be shown, it was loaded into the projector, almost ready to go. As it’s a 3D title, there’s a separate reel of film for both the left and right eye. These run through the projector around the front and then pop out the other side to go back onto two separate reels. The way they do it, is that the film is loaded from the centre of the reel. This means that once it’s done, there’s no need to rewind the reel back to the start point, unlike normal cinemas. This obviously saves time, which is a bonus, plus it means the film doesn’t suffer the extra stress – especially for something like Avatar, which they’ve sold over 51,000 tickets for, which is a lot of screenings.
In the same room they also have a selection of the other currently showing titles – such as Deep Sea, Space Station, and so on.
Now for the noisy part. The audio. It’s pretty simple really. The audio isn’t on the film itself, it’s delivered digitally, either on a DVD or HDD, and stored on one of the servers (two HDDs, one of which is a backup). The IMAX projector sends out a pulse to the server every so often, so the sound is always kept in sync. The soundtrack is a six channel mix, which is then delivered to all of the sixteen power amplifiers, and then to the bi-amped speakers within the theatre. So, obviously, it’s quite loud. And since there’s a DVD drive and microphones hooked up to it all, you actually could have a karaoke night if you rented the cinema. 
And a video of the control panel for the whole system (which I got to start the film with myself! 
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Finally, as well as the IMAX projector, there are two other projectors next to it – a 35mm projector, which is used for the pre-show trailers (eg, Pearl and Dean advertising), as well as a generic office-style projector which they use to show the PowerPoint presentation that shows upcoming films at the IMAX and other announcements.
And, of course, here’s a video of the projector in action. It’s very loud – if you’re standing next to it it sounds like a generator. And it’s not even loud compared to the pump room I mentioned earlier – that’s much louder.
So, that’s the projection room. Anyway, walking back out into the lobby and around the maze of passages, I also saw their dishwasher. Yes, a dishwasher. Technically, it’s not used for dishes, but it’s a big silver machine about the length of a car, which washes and dries off all the 3D glasses after they’re used, so they’re nice and clean for new people to use. They’re then carted back out to the lobby, where they’re handed out for the next screening. And lastly, we looked at the back of the screen itself – nothing much back there, it’s mostly just scaffolding holding up the screen (which, indecently, had to be lowered in through the roof when they built it because it’s so large), along with some surprisingly small speakers. The screen itself is silver, with millions of tiny holes in it for the sound to pass through (which most, if not all theatres have anyway). And that’s it!
An interesting thing (I hope I’m allowed to say this ) that Sally mentioned is that she’s flying off to Belgium in the next few weeks to go and find out more about the new digital IMAX projectors, to maybe upgrade the theatre to at a later date. That would mean that the projector wouldn’t need the huge reels behind it, nor would they need all the film either, as the films would then be delivered on a simple hard drive. And one hard drive is a lot better than 50 boxes of heavy plastic! Plus, of course, you get the benefits of going digital – the film doesn’t degrade, the quality is better, and so on.
Overall, it was very interesting seeing all the different parts of the cinema, finding out how it all works, and seeing it all in action, so I would like to, of course, say a big thank you to Sally, Caroline, and the rest of the people at Millennium Point for letting me go and see it all. 
Note: All the images shown have further notes explaining them on Flickr, so be sure to click through to see them. 
