Why do cinemas still use reels of film?

Mikol said:
...and that's currently why cinemas stick to film. The resolution of film in a cinema is MUCH higher than that of a DVD. For them to project an image of THAT SIZE on to a screen so large at the same resolution would be one huuuuuuuuuuuuuuuuge file.
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"Please increase the amount of virtual memory" :p

All this doesn't really matter anyway as the fools in the projection room can't get the projector set up right.
 
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Good post Dublove.

I find it very silly that most/all films are post-produced digitally (i.e. scanned), then put back onto film to be shown in cinemas. What a waste of time. It will be nice when things are filmed in digital, post-produced in digital, and displayed in digital. To whoever said that film reels are cheaper, i'm 99% sure thats not true. As for the cameras being harder to work, thats probably true but people will get there.

I'm excited about digital cinema (hell i wrote my dissertation on it :p). I'd like to think that in the saving they can get from lower distribution costs.. that saving will hopefully passed down to us. Thats the idea anyway. They're looking at a 90 percent saving in distribution costs with digital cinema. It will also be great to go to see a film without artifacts etc. (which i always spot now :(), whether its on the first showing, or the one hundredth. It will also be great to see other things played in cinemas.. football matches, TV shows (think '24' on the big screen!) etc.. :)

The problem the industry is having is that no one wants to release their films digitally because there arent enough digital screens to show them. On the flipside, no one wants to build/upgrade digital screens because there arent any films coming out. Someone has to take the plunge!

Oh, and people should stop getting so hung up about resolution. There's so many other factors that come into it, like colour gamut, brightness and contrast. ..Oh go on have a shameless quote from my diss :D

Resolution has long been one of the most contentious issues facing digital cinema advocates. The initial problem faced was that there was no real way to quantify resolution from 35mm film grains. However, the SMPTE Engineering Guide 5 goes some way to attempt this, by stating that a standard 35mm frame requires 80 lines per millimetre of resolution. As Sychowski (2000) explains:
“This means that 35mm film should thus be equivalent to 1,800 scan lines of resolution. Alternatively, given an over-simplification of one halide-particle equalling one pixel, academy aperture film would contain 11 mega-pixels at 4,500 x 2,500 resolution.” (Sychowski, 2000, p24)

However, what is important to note is that film degrades. A film reel could start off with a resolution similar to that quoted above, but after a few hundred plays the audience could end up watching at a resolution less than 1K (Sychowski, 2000). This simply will not happen with digital movie files.

There is an emotional issue in the film community when discussing resolution. Current HDTV is broadcast at a maximum resolution of 1,920 x 1,080 (Ive, 2004), and because of this the film community will not settle for anything less, as “...e-cinema should not just be 'as good as' 35mm, but substantially better, with 2K being the preferred standard.” (Sychowki, 2000, p24)
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That bit about HDTV can help to explain why there's been a delay too, as 4K projectors are only just emerging. There's also only one full-bandwidth 4K camera out there to capture content at 4K.
 
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Dublove said:
Film's that are shot in film are most commonly processed in a resolution termed '4k' That's 4096 pixels wide. It gets scanned in to editing computers and is 'graded' edited, cut, processed, effects added etc. etc.

When CGI is introduced they very commonly produce the CGI at 2048 pixels wide and then resize it times two to 4096 pixels wide. This is to save time as to render CGI at 4k resolution would take approx. 4x longer than at 2k.

So what does this all mean? Well for a start if the film reel the cinema receives has been properly mastered and their equipment is top spec then this will outclass any other method of displaying a movie in a cinema at this moment in time. There are no if's and buts on this.

Take dvd for example, 720 pixels wide maximum 16:9, 2.35:1 all 720 pixels wide but the wider it gets the less pixels there are in the y direction. HD1080 that's 1920 pixels wide maximum. Current DLP systems in cinemas are 2k projectors.

DLP projectors - Currently they cannot project as broad a range of colour, brightness or contrast as film. It does look good I agree but film is better.
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What he said :p
 
Why do cinemas use 24 frames per second?

Easy this one :) The answer is money and motion blur. Money because why shove more film though the camera than you need to. Motion blur because this makes the difference between frame 1 and 2 less noticeable meaning that 24fps is about the minimum you can get away with.

BUT

24fps on a tv is not the same as 24fps in the cinema. First is interlacing - people say PAL is 25fps but really it is half of one image at 50fps.

frame 1 A frame 1 B
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--------------- (arrgh vbulletin deletes the spaces)

Crude I know but these are lines of pixels that played twice as fast looks like 25fps.

So cinema 24fps and tv 25fps its only 1fps different so it's pretty much the same right? Wrong. Now the difference is how the we view them.

Cathode ray tubes draw an image on the tv tube line by line for each colour. At 60hz. This is why an old school tv flickers. Computer monitors go higher eliminating much of it i.e 90hz plus. But a film cinema projector puts the frames on the screen way faster all at once in thousandth's of seconds. This is the difference and I'm not even going to get into lcds :)

I can't wait until we have HDR 4k plus digital projectors at 100fps eliminating motion blur. It will probably make people feel ill.
 
there was a thing about this on bbc news web site a couple of days ago. There are talks of studios basically sending hard drives to cinemas and theyll just stick it in and hey presto. Personally i like the graininess of the films at cinemas. I like the clicks and specs of dust , but thats just me :)
 
Energize said:
No just use ffdshow.
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Which cannot improve on the original source material.

If something was filmed at ~24fps nothing is really going to take it up to 100fps and improve the image (it's either basically repeating frames, or trying to guess at what goes on between one source frame and the next - which can be very bad for the quality).
 
Energize said:
No just use ffdshow.
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I was waiting for you to blindly walk into that one :p, bottom line is you can't watch something at 100fps if it was filmed at 24fps. Not a chance you would know what the difference is in two films. :)

Werewolf covered it better probably, didn't even read it just expect it :p!
 
Energize said:
It makes it a lot smoother, I reccomend you try it out, the algorithm for motion estimation is very good.
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And can badly blur images, i've seen the results of very expensive industry standard tools used by DVD authoring companies cause really nasty problems, let alone something running in real time on non-dedicated consumer hardware.
 
You can't beat the contrast and resloution of analogue film.

Four years ago, in a Dublin cinema, I went to see "2001 - A Space Odyssey", which was projected using a special 70mm projector on the original 70mm film. (Most movies you see today are shot and projected on 35mm which is half the resolution.)

The sound was played on 6 track stereo soundtrack, the old, analogue version of 5.1 surround.

That was some experience I had.. today's digital could never match it.
 
Werewolf said:
Which cannot improve on the original source material.

If something was filmed at ~24fps nothing is really going to take it up to 100fps and improve the image (it's either basically repeating frames, or trying to guess at what goes on between one source frame and the next - which can be very bad for the quality).
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WinDVD's Trimension DNM does this very successfully. Although personally I prefer to watch movies at the correct 24fps, because otherwise it looks too real and can be quite disconcerting. WinDVD also lets you play 25fps DVDs at the correct 24fps so eliminating the nasty PAL speedup.
 
One time at the cinema someone had cocked up somewhere and the entire 35mm frame was being projected onto the screen.

We were able to see the sound men, director the lot.

I was amazed to find that this is not cut out from the final 35mm film.

It kind of spoiled the film, after 10minutes somebody must have told the manager as the film stopped, they sorted it out and then carried it on.
 
Tesla said:
One time at the cinema someone had cocked up somewhere and the entire 35mm frame was being projected onto the screen.

We were able to see the sound men, director the lot.

I was amazed to find that this is not cut out from the final 35mm film.

It kind of spoiled the film, after 10minutes somebody must have told the manager as the film stopped, they sorted it out and then carried it on.
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I don't think that's possible, we had a client going mad at us because in their shot from the camera it was showing the rigging equipment, the camera man realised this and zoomed in to remove it from the shot and the client thought we had zoomed it in, so we had to re-transfer it about 4 times until they got the hint and realised they were just being stupid. (they got a nice bill though for re-cleaning the neg, re-grading and re-transferring x4 :p )

Energiser, why the hell would you want to watch stuff at 100fps, surely the sound wouldn't be in proper sync, also for films 24p is probably the best way to view film, just like in the cinema and the speed at which the camera shot it.
 
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