Whats the resolution of a cinema screen?

hamd01

Active Member
I was talking with a friend last night, as to why high definition movies are becoming available for films 20 years old. My guess was that the films would have been filmed with a very high definition camera, in order to be able to produce the resolution required for a cinema screen. Is this the case?

What resolution is a cinema screen at? Is it progressive or interlaced?
 

mmace

Active Member
films are filmed on film, film has no resolution as it's not made up of pixels. for DVD's and HD the film is digitally scanned at a high resolution (usually more than 4 times the resolution of HD)

Films are 24 frames per second progressive

someone will probably answer more technically and more acurately then me, but the thing to remember is that it's on film where there are no pixels

another thing to think about is that the cinema screen is just a screen, the image comes from a projector behind
 

NicolasB

Distinguished Member
The effective resolution of 35mm film is about 4000x2000, so HD still has a long way to go before it catches up. What you actually see in the cinema, though, tends to be less sharp than you'd expect for that resolution. This is down to things happening after the original filming process: copying, scanning the film to do digital special effects work and then outputting it back onto celluloid, etc.

When domestic HD is capable of beating the resolution of IMax film, that will be cool. :) But that won't be for a long time. :mad:
 

StevenBagley

Active Member
While a 35mm negative has a 'resolution' of about 4k pixels, this is only on the camera negative. Traditionally, this is cut and from that an interpositive copy is made, and from the interpositive many internegatives are made. These internegatives are then used to make the prints seen in the cinemas.

Each of these copies eat away at the resolution to such an extent that what you'll see projected at the cinema probably only manages to have a little more resolution than SD video -- certainly less than can be achieved via HD displays.

Of course, advances in digital technology (and the use of Digital Intermediates) mean that modern films will tend to have more resolution than older ones.

Steven
 

Goose74

Active Member
StevenBagley said:
Each of these copies eat away at the resolution to such an extent that what you'll see projected at the cinema probably only manages to have a little more resolution than SD video -- certainly less than can be achieved via HD displays.
Steven

sorry I had to laugh at that - what a load of utter *****
The effective res of the average cinema film is around 2k down from arounf 4k from the neg. Still way more than 1080p
SD video projected in cinema looks, er well... horrible!
 

tryingtimes

Well-known Member
pedant :D
I was trying to clarify that Goose74 was suggesting that 2k was way better than 1080 when in fact they are very close.
But I don't agree with StevenBagley's comment about cinema being only slightly better than SD - but I guess it depends on the cinemas.
 

stefmcd

Active Member
What's a typical cinema screen - 300 inches?

Try blowing up Standard definition to that size and even at the back row it'll look like something John Logie Baird made in 1926!

Anybody with experience of projectors will understand how an image deteriorates rapidly as it's stretched over a larger area. If cinema projectors were focussing on an area as small as most tv screens the detail would be amazing.
:)
 

arfster

Active Member
Surely cinema projectors must use massive line multipliers? You'd be able to drive a bus between the pxels if not :cool:
 

mmace

Active Member
arfster said:
Surely cinema projectors must use massive line multipliers? You'd be able to drive a bus between the pxels if not :cool:
there's no pixels, it's on film (at the moment)
 

neilmcl

Well-known Member
ashmufc said:
I heard from someone that SWIII was filmed in 1080p or somehting like that, that guy is wrong right?
Yes, Revenge of the Sith was filmed primarily at 1080p/24 (4.4.4 RGB) using Sony HDC-F950 cameras, as well as Sin City and others.
 
R

Rimmer

Guest
Goose74 said:
sorry I had to laugh at that - what a load of utter *****
The effective res of the average cinema film is around 2k down from arounf 4k from the neg. Still way more than 1080p
SD video projected in cinema looks, er well... horrible!

Maybe the poster was exaggerating in claiming that release prints are little better than SD, but most of the films I see in the cinema look grainy and blurred. Obviously the quality of the projector and especially the lens can have a major impact on picture quality, but in my opinion the picture quality in the average cinema leaves a lot to be desired.
 

redpavlos

Active Member
Goose74 said:
sorry I had to laugh at that - what a load of utter *****
The effective res of the average cinema film is around 2k down from arounf 4k from the neg. Still way more than 1080p
SD video projected in cinema looks, er well... horrible!

Well, I think Steven is basically right.

While projected cinema film does offer somewhat more resolution, the difference in practice isn't as huge as you might think.

What matters is the effective res as seen in the cinema by the audience when projected, not what a static frame of celluloid might be capable of reproducing under a microscope in the lab.

Most cinema ads have for years been shot on film and then edited in component SD, scanned back onto film and then projected, and they can look reasonably good.

Having seen plenty of demos myself, a good HD 1080p projector on a cinema screen can look stunning. Partly depends on the equipment used, but 720p can look stunningly good too. Overall better, in my view, than film projected in the average cinema.

Do bear in mind that resolution is just one of the factors that contributes to the overall image quality.
 

Dave163

Active Member
neilmcl said:
Yes, Revenge of the Sith was filmed primarily at 1080p/24 (4.4.4 RGB) using Sony HDC-F950 cameras, as well as Sin City and others.

Almost right...since the Sony camera aspect ratio is 16:9 and doesn't have an anamorphic lens they filmed ROTS in 16:9 and chopped off the top and bottom to make it cinemascope 2.35:1 ratio, leaving it with just 700 lines.
 

Mr.D

Distinguished Member
Here we go again.

Highest resolution film is scanned at ( full ap 35mm frame) is 4096x3112. This is what is reffered to as "4K". 2K 2048x1556 is regarded as acceptable as on projection most people can't see a difference between 4k and 2k even on a rush print struck from the neg.

Scanning is often undertaken for the entire films these days to allow for digital grading , its not just a requirement for effects work.

The normal standard for motion picture film scanning is 10 bit log. This is regarded as full negative density ( to differentiate from print). To store this in a linear encoded system to the same percieved quality you would need about 18bits per channel. Video (including hidef ) is 8 bit linear at best.

Frankly 1080p looks like pish compared with film and the resolution is only half of it.
 

neilmcl

Well-known Member
Dave163 said:
Almost right...since the Sony camera aspect ratio is 16:9 and doesn't have an anamorphic lens they filmed ROTS in 16:9 and chopped off the top and bottom to make it cinemascope 2.35:1 ratio, leaving it with just 700 lines.
What do you mean "almost right", my statement was 100% correct, I never mentioned anything about aspect ratios. :rolleyes:
 
D

DTSFan2001

Guest
I work as a Projectionist at my local cinema, and I agree that picture quality is ultimately dependant on the quality of the equipment used. However, like Home Cinema, unless it is calibrated properly, you aren't going to get the best out of what you have. I would have to say that at my cinema, the pictures are out of this world, far better than the local rival. Contrast and definition are a pleasure to watch. This is not just due to the quality of the lenses (Schneider) but also having the projector bulbs aligned properly too (makes such a difference). As for cinemas adopting digital, I think it's still a way off. You have to justify the cost to the company, especially when the average joe isn't going to notice much difference between old and new. One or two cinemas will adopt at first (West End already have it in place for Chicken Little Digital 3D), but it won't be mainstream for at least a couple of years, possibly even as far as 2010.
 

ocdwhiteboard

Active Member
One or two cinemas will adopt at first (West End already have it in place for Chicken Little Digital 3D), but it won't be mainstream for at least a couple of years, possibly even as far as 2010.

I watched The Incredibles on a digital projector in Manchester's FilmWorks the year before last.
 

cyberheater

Well-known Member
Mr.D said:
The normal standard for motion picture film scanning is 10 bit log. This is regarded as full negative density ( to differentiate from print). To store this in a linear encoded system to the same percieved quality you would need about 18bits per channel. Video (including hidef ) is 8 bit linear at best.

Which is the bit that really impresses at the Cinema. My home cinema projector seems to have better contrast and blacks then my local cinema but the colours that you get at the cinema are simply gourgous.
Hopefully, Bluray or HD-DVD and home cinema projector technology will finally solve that problem.
 

The latest video from AVForums

Star Wars Andor, Woman King, more Star Trek 4K, Rings of Power & the latest TV, movies & 4K releases
Subscribe to our YouTube channel

Latest News

Starzplay streaming service rebrands as Lionsgate+
  • By Andy Bassett
  • Published
JVC adds Filmmaker Mode to latest D-ILA projector firmware
  • By Andy Bassett
  • Published
Bowers & Wilkins launches Px8 headphone
  • By Andy Bassett
  • Published
Sky set to launch its plug-and-play Sky Stream solution
  • By Ian Collen
  • Published
Movies Podcast: 26th September 2022
  • By Phil Hinton
  • Published
Support AVForums with Patreon

Top Bottom