How are digital movies distributed and screened? Every question answered!

How are digital movies distributed? Full explanation hereThe bulletin boards on our sister site urban75 have a good reputation for answering obscure questions posed by contributors, but rarely does a question get answered as comprehensively as when a poster enquired, “How are digital movies distributed?”

Here’s the original question:

Films that are shot on film have thousands of duplicates made, which are then shipped out to cinemas all over the world. Projectionists have to thread them into the projector and then show the film.

But how are films that were shot digitally distributed? Does the cinema get a DVD, or a laserdisc, or a hard drive, or what?

A poster called ‘Redeyes’ who works at  Apollo Cinemas was quick to answer – and then some!

I’m a projectionist at an all digital multiplex, we converted from 35mm in February.

Here’s the hard drive (called a DCP – Digital Cinema Package) for The Lovely Bones

How are digital movies distributed? Full explanation here

File size for that film was about 150 gig. Avatar 3D is about 280 GB.

We get the drives couriered to us and generally the keys to open the files are emailed to us.

Regular hard drives?

A poster responded, expressing surprise that couriers are still needed to move digital data around, and asking if they used a standard hard drive in a special caddy.

Yeah, it’s a standard hard drive, the caddy slips off so we can upload the data via a CRU port on our main server. Takes about 40 minutes to transfer a feature across from a portable drive.

The technology is in place to deliver the files via satellite but from what I’m lead to believe there’s still concerns from the distributors about the satellite feed being intercepted, security of the data etc.

The current method is pretty solid though. Even when the file is on our main server we still can’t play the film until we get a ‘key’ from the distributors. The ‘key’ is a coded file made specifically for our site telling the computer which screen we can play the film in and also to only allow it to be played within a specific time period.

How about DVDs?

Redeyes was asked if digital movies were exclusively distributed on hard drives or whether other media like DVDs were used.

All the ‘mainstream’ films come on hard drives. We have played a couple of films from DVD but they don’t look too good upscaled to 4K (we’re using the Sony 4K projectors). Luckily pretty much everything we need is available on hard drive, we’re a mainstream cinema in a fairly large town so our film booker tends to stick with the run of the mill crowd pleasers.

Blu-rays look really great, though we’ve yet to have anything supplied to us on that format. I’ve tried out a couple of my own though…


Here’s how the discussion continued:

“Surely shipping Blu-rays with encryption keys would be a whole lot more cost effective than shipping hard drives?”

The files on the drives are JPEG2000 and come in either 2k or 4k resolution with the files size being anything from 50gig to 400gig+. I’m not sure if a Blu-ray could carry that data (I think standard Blu-rays can hold up to 50gig?), plus it would still need ripping from the disc and transferring to the main server.

Also the disc would still have to be sent via courier to assure the distributors that the item was being sent securely. I doubt the charges would be that much different between sending a box with a Blu-ray in or a box with a hard drive in?

“What sort of signal is the server sending the projector out of interest?
and what’s stopping you recording the output”

Not sure what you mean by ‘signal’, the files are JPEG2000 and are either 2k or 4k in resolution. The 3D is 2k dual image using the Sony RealD system.

We can’t record the output as the part of the projector where the ‘key’ unlocks the ‘film’ is housed in an enclosure that is riddled with security devices. If I was to try and take a panel off that part of the projector the whole thing would shut down and we could only get back up and running after security checks are done and Sony re-set the server. Plus there’s no ‘out’ sockets to take a feed from, you’d have to hack into the electronics to get a signal output.

The only way to record the film would be to film it off the screen and even then each projector puts an invisible watermark on the film which can be used to identify which cinema was showing the film, what time the show was played and even which member of staff was on duty at that time.

Has digital got rid of projectionists jobs?

“Do you still have jobs? I thought digital multiplexes could operate with just one guy running round the different screens and pressing play, rather than having one projectionist per movie? “

Yes, I have a job. Though instead of having three projectionists we now have just the two. One person on duty at a time. The automation that digital allows means we can finish our shifts before the last film has finished, whereas with 35mm we had to stay until the end, hence the loss of hours for our department. We don’t need to run around pressing play either, it’s all controlled from one main control centre.

Then again when we had 35mm we didn’t need to run around pressing play either as the projectors set themselves off as they had onboard timers. There was also still only one person on duty at a time then too and we have 9 screens to look after.

Back when we had 35mm the main bulk of my day was taken up by threading the projectors after each show and building up and breaking down the prints that were either coming in or on their way out. These days now we’re digital my job is more IT based with most of my work involving the transferring of the film files from the hard drives to our server, chasing up keys, scheduling the shows and maintenance around the building and in the projection box.

“Oh I thought projectionists had to sit through the film changing reels every so often (when the black oval pops up in the top right?) and trying not to get their hair caught in the thing (I saw a copy of Natural Born Killers get melted in two places this way by one unfortunate guy). I guess maybe you had more advanced projectors that you could load the entire movie onto?”

No, back in the 60’s platter systems were invented that effectively changed the cinema industry. These systems allowed a film to be made up into one big reel and played from start to finish without the need for reel changes. This meant that multiplexes could have loads of screens and not have to pay someone to sit next to the projector and change reels every 40 minutes or so.

Here’s one of our old platters with a copy of AVATAR on…

How are digital movies distributed? Full explanation here

We’d take the film from the centre and thread it through the projector so that when it came out the other side it would wind back onto the spare platter…

How are digital movies distributed? Full explanation here

When the film had finished it was ready to go again, we’d take the film and lace it through the projector and it would run back onto the platter it was on previously.

Here’s one of our old 35mm projectors…

How are digital movies distributed? Full explanation here

And the new digital projector that replaced it…

How are digital movies distributed? Full explanation here

Are hard drives shared?

Do the HDs get delivered to multiple cinemas, or does each site get it’s own HDD? I realise that a load of HDs is still going to be a lot cheaper than 35mm (I used to book cinema advertising and the first time I was presented with the bill for the film I nearly fell over!), but that seems like a lot of wasted HDs (or do you send them back when they’ve been copied?)

For the ‘big’ films like, say, TOY STORY 3 each site will get their own HD. Smaller independent films will have a lot fewer HDs which will be passed around. We had a show of LA TRAVIATA a few weeks back and we had to transfer it straight to our system and a courier picked it up the next day so it could go to another site.

All the HDs get returned and re-used though.

Is digital as good as film?

What do you think about the resolution and quality of the digital product? So far in the digital cinemas I been to, I have not been impressed by the digital copy. They all seem to have a problem with slow panned scenes looking jerky.

After having looked at 35mm everyday since I started working in the cinema, which was back in 1997, I am really impressed with how the films look on screen at our place.

Bear in mind though that we are using the Sony Cine Alta 4K projectors which can not only display 4K images but also upscales 2K images to 4K.

2K being slightly higher res than 1080p and 4K being four times the res of 2K

I’d stick my neck out and say that the Sony projectors put out an image that is as good as a perfectly presented 35mm show.

I’ve not had chance to see any films shown on other digital cinema projectors though so can’t really comment on the quality of those. Though I do know most of the digital projectors currently being used in cinemas are only 2K.

View the original thread here.