Film-Tech Forum ARCHIVE: Screen Aspect Ratio

This is topic Screen Aspect Ratio in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Alex Aye (Member # 1525) on 12-13-2002, 01:58 PM:

Hi All!

I am a newbie here. So feel free to educate me. For commercial theaters, what can a film operator expect when the new reels arrive -- in terms of aspect ratio?

Are there precisely 2 or 3 formats that can be shown at any modern commercial theater? I have noticed that movie posters never advertise the aspect ratio even though there are several widescreen formats, where almost all of them appear to be a product of PanaVision.

Any difference when foreign films arrive? Or are they Americanized before they are distributed?

I do know, one thing, that is, there is no such thing as 16:9 in cinema. It is a HDTV standard which is fairly close to one of the cinema ratios like 1:1.835 or something.

Thanks ahead for your info...
Alex

Posted by Adam Fraser (Member # 1074) on 12-13-2002, 02:06 PM:

Modern American films come in 2 standard aspect ratios.
"Flat" 1.85:1
"Scope" 2.39:1 Requires a cinemascope (anamorphic) lens to "unsqueeze" the image.

Posted by Joe Beres (Member # 678) on 12-13-2002, 02:06 PM:

Hey Alex, Welcome!

As far as mainstream American film is concerned, there are two aspect ratios that you will see: 1.85:1 and 2.39:1 (Anamorphic/Cinemascope). Typically, those are the only two aspect ratios any mainstream commercial American theater is equiped to handle.

Foreign films are a little more difficult to pin down. A common aspect ratio for European films is 1.66:1, and the arthouse theaters that often present those films are (hopefully) equipped with the proper lenses and aperture plates.

If a foregn film shot for 1.66:1 presentation becomes a mainstream success, it will almost always be shown at 1.85:1 at a mainstream multiplex. (These cases are fairly rare, but recent examples are Life is Beautiful and Crouching Tiger Hidden Dragon.) Hopefully, the subtitles will be positioned so that they can be shown without "cutting off the heads" at the top of the screen.

Posted by Michael Schaffer (Member # 1204) on 12-13-2002, 02:28 PM:

Wasn`t "Crouching Tiger" scope?
In Europe, 1:1,66 becomes rarer and rarer and most multiplex theaters aren`t equipped to show it anymore. Recently, the French film "Huit Femmes (Eight Women)" played here and it presented some problems as it was in 1:1,77 (the same aspect ratio as 16:9 TV), a format which is still in use in France sometimes but is otherwise more or less extinct. During the Berlin Film Festival 2001, I played a lot of Vietnamese films and a lot of them were 1:1,77. Obviously this is an element which has survived from the time Vietnam was a French colony. Interestingly, the leaders were all in French, too.

Posted by Alex Aye (Member # 1525) on 12-13-2002, 02:40 PM:

Merci beaucoup...folks.

I need to clarify one thing. There could be two different things we are talking about: film ratio and screen ratio.

I think we are discussing "screen ratio", not "film ratio". As we all know, since the actual film includes sound tracks and possibly vertically-squeezed image -- the film aspect ratio does not belong to this topic. Have we been off course??

So, there are 2 screen formats:
(1) 1:1.85 known as Flat, and
(2) 1:2.35 known as Scope.

Or is the screen ratio for the latter is 1:2.39?

Thanks,
Merci,
Gracias,
Alex.

Posted by Alex Aye (Member # 1525) on 12-13-2002, 02:54 PM:

sorry, I meant horizontally-squeezed image that is recorded on the film, which is later expanded back on screen by the projection lenses.

Posted by Tim Reed (Member # 137) on 12-13-2002, 05:23 PM:

Hi, Alex. Welcome aboard! 35mm anamorphic projection used to be 2.35:1, but was changed a few years ago to 2.39:1, to reduce the possibility of negative splice marks showing on screen.

The "screen ratio" depends on how well the theatre was constructed, in-spec or out. 1.85:1 on the film is still 1.85:1, regardless of what's in the theatre. Having a screen of a differing proportion doesn't change the standard, but it does crop away at important action and title safe areas of the image, for audiences in that room.

Posted by Martin Brooks (Member # 1269) on 12-13-2002, 06:00 PM:

I think what some of the above posts were trying to express was that there is a difference between negative specs and projected specs.

I believe that the current SMPTE standard is as follows, based on the RP40 alignment film:
Anamorphic: .825 x .690 x 2:1 unsqueeze = 2.391:1.
Widescreen:.825 x .448 = 1.842:1 (called 1.85)
HDTV Compatible: .825 x .464 = 1.778:1
European: .825 x .497 = 1.66: 1
Classic: .825 x .602 = 1.37:1 (commonly called 1.35)

There was also an aperture in use in the 1960s of .825 x .472 = 1.748:1 (called 1.75). I believe a lot of Disney releases were intended to be shown at this aperture.

You should note that all standards are voluntary. And due to architectural and lens limitations, most theatres never show the exactly correct aspect ratio anyway. And there are other standards, although they are generally very similar. For example, NATO maintains its own standard, which I believe uses slightly different dimensions than the SMPTE standard, although I don't have the exact specs handy.

The other factor is that standards have changed over time. For example, if you go back to the 1969 edition of the American Cinematographers Manual, they quote the projected widescreen spec as .825 x .446 and the "Academy" spec as .825 x .600. The old anamorphic spec was .839 x .715 x 2.0 = 2.347:1, but it was discovered that if theatres actually projected the full .715 height, splices were visible, so this was changed a few years later to .839 x .700, then sometime before 1986 to .838 x .7 and has since been reduced to .825 x .690. This might make a bit of a difference if you played old prints, but when you do the math you discover that on a 40 foot wide screen, you would only lose 4 inches of width on each side of the screen if you played a print made for an .839 aperture at .825.

Posted by Joe Beres (Member # 678) on 12-13-2002, 07:39 PM:

Michael, yes, Crouching Tiger was scope. I was just citing it as a foreign film that made it's way into mainstream US cinemas.

Posted by John Pytlak (Member # 331) on 12-17-2002, 09:01 AM:

Standard SMPTE 195 specifies projectable image area for 35mm prints:

http://www.smpte.org/smpte_store/standards/

Here is the evolution of the "scope" image area:

http://www.widescreenmuseum.com/widescreen/apertures.htm

____________________________________________________________________

From 1957 through today, there have been a number of small changes to the anamorphic projector aperture recommended standards. John P. Pytlak of Eastman Kodak dug through countless back issues of the SMPTE Journal in order to provide the following chronology of the changes to the standards:

The March 1957 SMPTE Journal has PH22.104-1957, the standard for 2.55:1 anamorphic (no optical track), with an aperture size of 0.912 X 0.715 inches. Notice of withdrawal of this standard was in the January 1964 Journal.

The December 1957 SMPTE Journal has PH22.106-1957 for 2.35:1 anamorphic, with an aperture of 0.839 X 0.715 inches. It was unchanged in the September 1964 Journal. The November 1965 SMPTE Journal published PH22.106-1965 still with the 0.839 X 0.715 aperture size.

In the September 1970 SMPTE Journal, a new draft of PH22.106 was proposed, with an aperture size of 0.838 X 0.700 inches, to minimize the flashes at splices. This was republished as standard PH22.106-1971 in the October 1971 issue.

In the June 1976 SMPTE Journal, the two (flat and scope) projectable image area standards (PH22.58 and PH22.106) were consolidated into one standard and renamed PH22.195. The publication of PH22.195-1984 in the October 1984 Journal still had the scope area as 0.700 X 0.838 inches.

The June 1992 SMPTE Journal published a proposed revision, with a scope area of 0.690 X 0.825 inches. In August 1993, the standard was published as SMPTE 195-1993, with the current area of 0.690 X 0.825 inches. So August 1993 is when the two formats became the same width of 0.825 inches.

Posted by Michael Schaffer (Member # 1204) on 12-17-2002, 10:31 AM:

Why does it say "the end of plastic film" under interests in your profile, Alex?

Posted by John Pytlak (Member # 331) on 12-17-2002, 01:09 PM:

From Alex's website:

http://scollege.com/

South College Digital is founded by Alex Aye in honor of a dear fellow photographer -- late Louisa Stanley. Louisa lived on South College Street in Pittsburg, Kansas.
Alex is a consultant in Information Technology and Telecommunications. South College acts as a medium for Alex to communicate to business partners, friends, and family. Alex's main interests and expertise of photography, digital imaging, and workflow management are reflected on this website.

Following on-line albums are chronicles of special newsworthy events. For questions and comments, contact Alex at alex@scollege.com or (913) 484-2554.

I'm sure Alex knows that film and digital imaging peacefully co-exist:

InfoImaging

Kodak Research and Development

Kodak EI Chief Technical Officer

Kodak Digital Cinema

Posted by Frank Angel (Member # 248) on 12-17-2002, 10:23 PM:

Martin said: >For example, NATO maintains its own standard, which I believe uses slightly different dimensions than the SMPTE standard,<

Is this true? Why would NATO's aspect ratio specs be different than SMPTE's? If a film is intended to be projected at 1.85 flat or 2.39 scope, why would a theatre use a different aspect ratio?

Frank

Posted by John Pytlak (Member # 331) on 12-18-2002, 09:00 AM:

NATO does NOT have a different standard for projectable image area. NATO encourages theatres to follow SMPTE Standards:

http://www.smpte.org/smpte_store/standards/

http://www.smpte.org/smpte_store/standards/cd_standards.cfm