Film-Tech Forum ARCHIVE: I need DVD aspect ratio help

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Posted by George May (Member # 1060) on 08-04-2008, 05:31 AM:

Like many of you I'm beginning to screen DVD material from a laptop when there is no 35 mm print and when I can sort out the licensing.

I'm a mobile outfit so need to have any array of lenses to suit the different venues I go to. I've got a 4,000 lumen projector which was designed for interchangeable lenses. The manufacturer's lenses are, IMO, eye-wateringly expensive. So I've modified my projector to take a mounting plate and sleeve into which my standard 35 mm projector lenses will fit.

At each site I need to know the throw and the aspect ratio to select the right lens to fill the screen. And I'm thoroughly confused! Here's a selection of the specifications on some DVDs I've seen recently:

"1.85:1 Widescreen" (Sin City)
"1.78 Anamorphic" (Fitzcarraldo)
"Widescreen 2.35:1" (The Talented Mr Ripley(which plays at 16:9!))
"16:9 full height anamorphic" (The Cement Garden)
"1.85:1 Anamorphic" (The Long Day Closes)
"2.35:1 Anamorphic" (La Vie de Jesus)

What's going on?

Thanks and best wishes to you all.

George

Posted by Cameron Glendinning (Member # 3516) on 08-04-2008, 06:00 AM:

Ok, projecting DVD, Do you have a widescreen projector? or is it 4/3, the panasonic 5000 series is stated as being 14/9 but you may as well think of it as 4/3.

If you have a 4/3 style projector do you have a 1.5 x anamorphic or old style varamorph (light eater).

Remember that your dvd player can also vary the output ie letterbox widescreen or pillarbox 4/3 or output a 1.5 squeezed widescreen image ect and that the projector will also have settings that do similar things that can also cause confusion.

The other factor is that video projectors aren't very noisy so you can even place them at the front of the audience and keystone correct ect.

I hope this helps or at least is a start.

Posted by John Wilson (Member # 269) on 08-04-2008, 06:36 AM:

Mr. Ripley was 1.85:1 so don't know what the 2.35:1 rubbish is all about on the DVD packaging.

There are versions of The Magnificent Seven here on DVD that have the ratio as 1.85 on the packaging. [Roll Eyes]

Posted by Cameron Glendinning (Member # 3516) on 08-04-2008, 06:51 AM:

I recently saw a dvd of a Room with a View claiming to be in 2.35/1 on its back cover, thankfully it was as I remembered (running it so many times) presented in flat.

Posted by Lyle Romer (Member # 1266) on 08-04-2008, 07:12 AM:

On DVD anamporphic has nothing to do with aspect ratio. It is a way of encoding that utilizes the entire 4:3 picture (DVD native ratio) resolution to make a widescreen picture.

AFAIK, all "flat" films on DVD are 16:9 on DVD. I've never seen any small letterbox to make it 1.85:1.

Scope I've never measured so I don't know if they letterbox at 2.35:1 or 2.39:1 or a mix depending on title.

Posted by Jonathon Miller (Member # 4863) on 08-04-2008, 11:46 AM:

Most 1.85:1 stuff of current films are opened up to 1.78:1 for home video transfers these days.

DVDs can be an aspect ratio within either a 4:3 or 16:9 frame. As long as you figure out whether the transfer is anamorphic or not, you shouldn't have too many problems.

I don't envy you if you try to show a 2.35 film in "scope" as it were, in case there are subtitles that were originally on the print, but are on the DVD as a subtitle track. They usually end up in the black bars, so if you've blown the image up and masked the top and bottom off, you're shit out of luck.

Also, plenty of older DVDs are non-anamorphic 1.85/2.35. Most of these are from older masters, the most notably ones being the "original versions" of the star wars films included as a bonus disc with the individual re-releases of sw/empire/jedi.

Posted by Mike Schindler (Member # 1309) on 08-04-2008, 11:54 AM:

Am I right in thinking that you're not confused by the technical aspect, but more by how the DVDs are labeled? If so, the two factors which need to be determined are whether it's a 16:9 transfer or 4:3 transfer, and what the aspect ratio of the actual movie is. This can be difficult because, as your examples show, there is no uniform labeling, and lots of times things are mislabeled.

Like Lyle stated, anamorphic is the same as 16:9. All of the DVDs you listed appear to be 16:9. Lots of times, if the DVD has a 4:3 transfer, this will not be indicated on the box. Really, the only way to be sure is to run the disc itself.

quote: Lyle Romer
AFAIK, all "flat" films on DVD are 16:9 on DVD. I've never seen any small letterbox to make it 1.85:1.

Actually there are a good number of flat movies which are in 1.85:1 on DVD. Many TV's cover the black bars with overscan, but they're there. It seems like Universal, Fox, and some others frame them at 1.85. Warner Bros. does full frame 16:9 transfers, as do others.

Also, if you're trying to determine the best version of a given movie to show (in terms of picture and sound quality), there's a great website here which compares all of the various releases of a particular movie in great detail.

Posted by Frank Angel (Member # 248) on 08-04-2008, 01:03 PM:

In this same vein, I have never heard a good explanation of why lenses for a digital projector need to be so much more expensive than film projector lenses. The both lens are looking at an aperture that needs to be focused onto a screen -- what's the difference if that aperture contains a frame of film or DMD? What is the 2-3 thousand dollar difference?

But then I also said the same thing about slide projector lenses which, seeing as how they needed to see an area of a 35mm slide which is larger than 4/35mm film, they have to have an even larger rear element than for 35mm film, which means it would be even easier for them to achieve good edge-to-edge focus in a 4/35 aperture. And slide projector lenses are lots cheaper than cine lenses. [Confused]

Posted by Scott Norwood (Member # 30) on 08-04-2008, 01:20 PM:

I've actually used a regular Kodak slide projector lens in a video projector (Sony LCD unit). It more-or-less worked, but the image was not as sharp as with the video projector lens. No idea why. Focusing involved physically moving the lens back and forth.

In any case, SD video will be in one of three formats: full-frame 1.33, letterbox widescreen, and anamorphic widescreen. Except when using a 1.33 screen, a zoom lens is pretty much required in order to accommodate all of these and to fill at least one dimension of whatever aspect ratio the screen happens to be. Most zoom lenses don't have enough range to fill a common-height screen for all formats from 1.33 to 2.35, however.

Posted by Brian Guckian (Member # 1678) on 08-04-2008, 01:29 PM:

I had to recently show a DVD copy of Peter Weir's Master and Commander: The Far Side of the World on a 25ft screen in a cinema I was working in.

The DVD aspect ratio was labelled as 2.35:1 but also as "16:9 Enhanced".

Despite setting everything up very carefully, the image on projection (and on the monitor) was slightly stretched horizontally and there was nothing that could be done about it (all the settings were checked; i.e. the projector was not mistakenly set to "unsqueeze" the material [which was 4x3 letterboxed]...nor was the DVD player).

The overall quality was also terrible and a betrayal of the huge craftsmanship that went into the film. The WXGA LCD projector used (posited as "good enough" for the screening) was bright enough but obviously couldn't possibly achieve the necessary contrast, colour gamut or resolution, so the picture fell apart, especially in the film's many dark or low-lit scenes.

Sound was Lt Rt decoded in the cinema's Dolby CP650 as we couldn't interface the DVD player's 5.1 output with the CP (would have needed at least the I/O Option Card fitted).

Ultimately the specification of the DVD format seems hard to control.
You're handed the disc - which can have a myriad of authoring characteristics - and told to get on with it; and in this case a print could have been screened, but no, it would have been "too expensive" (it was a private hire).

I believe screening DVDs instead of 35mm prints (so-called "DVD substitution") raises serious ethical problems as the format was never designed for large-screen projection, but rather purely for domestic use.

What about looking at 35mm print non-availability another way - and this requires courage - and saying, well, if a print isn't available, then the title can't be shown?

Although this might go against a well-meaning "the show must go on" ethos, it does protect the integrity of the work of the great numbers of craftspeople who bring these films to fruition.

Posted by Monte L Fullmer (Member # 2797) on 08-04-2008, 09:12 PM:

quote: Brian Guckian
The DVD aspect ratio was labelled as 2.35:1 but also as "16:9 Enhanced".

16:9 enhanced basically means that the playback info on the disc is actually squeezed for the pict to be played back in a true scope form for widescreen TV's...

Standard 4:3 as a normal TV displays, the widescreen display is like the hard matted trailers - assigned to fit in that certain display parameter.

..it's a pixel programming thing.

Posted by Darryl Spicer (Member # 711) on 08-04-2008, 09:29 PM:

I am not sure about this because I haven't investigated it to see but I think the anamorphic squeeze they use on the DVD is different than what you will find on 35mm film. So if you try to send an unsqueezed DVD image through an anamorphic for film it will look over pulled out. If someone knows for sure that it would be acurate let us know. I have often wondered if the same squeeze ratio was used for scope on DVD as it is on film.

Posted by Lyle Romer (Member # 1266) on 08-04-2008, 10:59 PM:

I would assume the DVD anamorphic squeeze is 1.33. 1.33:1 x 1.33 = 1.77:1. Depending on the numberr of 3's you use in the calculation it gets pretty close to 1.78:1 of a widescreen TV. This is obviosly a different sqeeze than 'scope 35mm film.

Posted by Carl Martin (Member # 1146) on 08-05-2008, 01:53 AM:

quote: Brian Guckian
What about looking at 35mm print non-availability another way - and this requires courage - and saying, well, if a print isn't available, then the title can't be shown?

you might even encourage the striking of a new print. settling for a dvd, however, could have precisely the opposite effect.

Posted by Cameron Glendinning (Member # 3516) on 08-05-2008, 05:29 AM:

quote: Darryl Spicer
but I think the anamorphic squeeze they use on the DVD is different than what you will find on 35mm film

yes film is a 2x squeeze, Video is a 1.5x squeeze.

I still have at least 3 old 35mm Varamorph lenses in the garage where you can ajust the squeeze from none to 2x, so they can be used for video.

Also there are DIY sites that will show you how to build a video anarmorphic lens, attach them to a 1.33 chip projector for a full resolution 1.75 image(16/9), or attach them to a 16/9 chip projector for a full resolution 2.4 scope image!

Posted by Brian Guckian (Member # 1678) on 08-05-2008, 07:34 AM:

quote: Monte L Fullmer
16:9 enhanced basically means that the playback info on the disc is actually squeezed for the pict to be played back in a true scope form for widescreen TV's...

Many thanks Monte - we also checked the projector's "unsqueeze" mode to rule out the possibility we were inadvertently unsqueezing the material...no cigar as doing this stretched the image far beyond what we were seeing - confirming it was not a 16:9 anamorphosis problem.

BTW it also underlined the need to have proper test materials to hand...we should have had a copy of Video Essentials [Embarrassed]

Posted by Leo Enticknap (Member # 534) on 08-05-2008, 11:21 AM:

quote: Frank Angel
In this same vein, I have never heard a good explanation of why lenses for a digital projector need to be so much more expensive than film projector lenses. The both lens are looking at an aperture that needs to be focused onto a screen -- what's the difference if that aperture contains a frame of film or DMD? What is the 2-3 thousand dollar difference?

I'd also have thought that by now, video projector lenses are being made in greater numbers than film projector lenses, thereby enabling better economies of scale.

Posted by Larry Myers (Member # 738) on 08-05-2008, 11:34 AM:

The way I understand it, all 2.35 DVD's that are enhanced (1.5 anamorphic) will have bars to make the image 2.35. Then 1.85 enhanced image will not have the bars. If your using a digital projector, the 1.85 image enhanced image is the best you can get with all the pixels being in use in the projector. Less zoom will be need to fill the screen height.

You can get 1.5 anamorphic lens for your DVD projector so you can play the 1.5 squished image. Some say this is a better way to go rather then letting the projector electronics unsquish the image.

I have never seen a 2.35 DVD image without the bars.

Posted by Cameron Glendinning (Member # 3516) on 08-06-2008, 05:13 AM:

quote: Larry Myers
I have never seen a 2.35 DVD image without the bars.

Well Larry the panasonic 100e was a popular choice for the diy crowd to modify with the swing in 1.5 x anamorphics. As a scope image on dvd is letterboxed exactly the same way as a leterboxed 1.77 presented in 1.33.

So for 40% more resolution for a scope presentation in hd dvd or blu ray in your screening room, simply add a video anamorphic and select zoom 1 setting in the menu. [Cool]

Posted by Larry Myers (Member # 738) on 08-06-2008, 03:40 PM:

That might be so but as far as I know, a zoom feature in the electronics would not increase the stored image area resolution of each frame on the DVD. Each frame on the DVD would still have the bar. With the Zoom feature, the bar would now be zoomed out in the DVD player.

On the other hand if the bar is added by the DVD player and not on the DVD itself, then yes, a zoom feature would give the extra resolution.

I guess what I don't understand is exactly how a anamorphic image is stored on a DVD disc frame by frame.

Posted by Tony Bandiera Jr (Member # 2365) on 08-06-2008, 11:21 PM:

To put this situation in perspective, keep one thing in mind:

Film aspect ratios have been strictly defined by SMPTE and industry practice, so 1:85 is just that, no matter who's film you're screening.

DVD's are subject to the whims of the authoring process and engineers, so THERE IS NO STANDARD!!!!

That's why, even on films from the same studio, there are likely size differences on their own films when finally authored on DVD. Take any three or more movies from the same studio, all with the same theatrical aspect ratios, and you will likely find them all to have differing image sizes.

Best bet for those who are doing traveling video presentations, get a range of zoom lenses for your projector so you can fit the picture to most screens.

Some projectors, like many of the Christies, can also electronically resize images, trimming width and height together or independently.

I have a client where we added indepeendant top and bottom maskings to their screening room so they can adjust for off-centered heights on dvds (another common problem.)

Posted by Frank Angel (Member # 248) on 10-11-2008, 04:54 PM:

quote: Brian Guckian
I believe screening DVDs instead of 35mm prints (so-called "DVD substitution") raises serious ethical problems as the format was never designed for large-screen projection, but rather purely for domestic use.

What about looking at 35mm print non-availability another way - and this requires courage - and saying, well, if a print isn't available, then the title can't be shown?

Brian, I feel your pain. At one venue where I work they spent a lot of $$ on their non-DCI compliant video projector and have taken, as you said, to doing the DVD substitution thing when there is no 35mm print. BUT, that too EASILY morphs into doing the DVD substitution just for convenience. And because they think they can save loads of money. Yes, if they don't mind breaking international copyright laws. Just remind them that even if they happen to get a DVD, they STILL have to pay the same exhibition license to run it as they would booking the 35mm print. That reality takes most of the money incentive out of their sail.

I have actually told the suits that I will not run a DVD if they don't assured me that they have a licence to exhibit it. Buying the DVD doesn't constitute an exhibition license, and they damn well know it; most times they just choose to ignore it. Tell then to read the FBI and Interpol Warning.

They are a lot more likely to book the 35mm print if they have to go to the same distributor and pay the same money to book the DVD exhibtion rights as the do the print. Also remind them that even worse than risking FBI agents decending on their offices, if they get caught running a DVD without obtaining the proper license, they more than likely will be blocked by the studios from booking ANY product regardless of the format. I have seen more than one place blacklisted because of such shenanagans. And it spreads like wildfire -- it's a small cirlce, distributor's bookers; one studio hears about problems at a venue and before you know it, NONE of them will book product. Sober them up, Brian -- put the fear of Interpol into them! Quietly tell them you just happen to have the Dublin Interpol telephone number in your phone directory!

Posted by Stephen Furley (Member # 1277) on 10-12-2008, 04:48 AM:

quote:
At each site I need to know the throw and the aspect ratio to select the right lens to fill the screen. And I'm thoroughly confused!

George,

Take care not to confuse the aspect ratio of the video with that of the image recorded on it; there's also the aspect ratio of the pixels to confuse things further. Note that the ratio of the number of pixels is not the same ans the ratio of the size of the picture; i.e. the pixels are not 'square', ans they normally are when dealing with still photographs.

The number of pixels on a DVD doesn't change whatever the aspect ratio of the video; it's normally 720x576 for PAL and 720x480 for NTSC; certain lower resolutions are allowed, but are seldom used. They are roughly VHS quality, and are mainly used by long play modes in domestic DVD recorders. I can never remember the numbers, and had to look them up. They are:

MPEG-2, 525/60 (NTSC): 720x480, 704x480, 352x480, 352x240
MPEG-2, 625/50 (PAL): 720x576, 704x576, 352x576, 352x288
MPEG-1, 525/60 (NTSC): 352x240
MPEG-1, 625/50 (PAL): 352x288

You can almost certainly forget about these if you're dealing only with commercial recordings of feature films.

The video can be in two aspect ratios, 3:4 or 16:9. Each 'title' on a disk will be in one ratio or the other, but different titles on the same disk can have different aspect ratios, e.g. there might be a 4:3 copyright notice before a 16:9 feature. Dividing both sides by the vertical number, and rounding off to two decimal places, to get them into the same format as film aspect ratios, 4:3 becomes 1.33 and 16:9 becomes 1.78.

Unless you are dealing with silent film, or something smaller than 35mm, these ratios do not exactly match those of the usual film formats, 1.37, 1.66, 1.85 and 2.35, nor indeed the less common ones; either the image must be cropped, or part of the video frame will be black, usually 'letterboxed' with black bars at the top and bottom, but sometimes 'pillarboxed', where the film image is narrower than the video one.

1.37 film is normally used with 4:3 video, and the difference is very slight.

1.66 film is usually letterboxed on 4:3, or simply cropped to 1.78 on 16:9. It is occasionally pillarboxed on 16:9.

1.85 film can be on 4:3 video, either cropped to that ratio, or letterboxed within it, or it can be on 16:9 video, either slightly cropped or slightly letterboxed.

2.35 film is severely cropped or letterboxed when used with 4:3 video, and this is seldom done now, mainly when an old 4:3 master originally made for a VHS or Laserdisc release has been used. 2.35 film is normally letterboxed within 16:9 these days.

What happens when the ratio of the display doesn't match that of the video? Most 4:3 televisions cannot accept 16:9 video, and will display it stretched vertically; a few of the more recent sets, and some 4:3 projectors, can compress the image vertically to compensate. All DVD players can convert 16:9 video to 4:3, either by cropping or by letterboxing. When a DVD is authored it is possible to allow both of these modes, or to set a flag which will disable one of them, and therefore force the other, when 16:9 material is being used with a 4:3 display. With a projector there's also the option of using an anamorphic lens.

16:9 displays normally display 4:3 material pillarboxed in the centre of the screen; this is fine if the image is in that format, but a widescreen image letterboxed on 4:3 video will give a very small picture in the centre of the screen. Widescreen displays can usually enlarge this image to fill the whole screen, but of course the resolution is much less than it would be with 16:9 material.

quote: George May
Here's a selection of the specifications on some DVDs I've seen recently:

"1.85:1 Widescreen" (Sin City)
"1.78 Anamorphic" (Fitzcarraldo)
"Widescreen 2.35:1" (The Talented Mr Ripley(which plays at 16:9!))
"16:9 full height anamorphic" (The Cement Garden)
"1.85:1 Anamorphic" (The Long Day Closes)
"2.35:1 Anamorphic" (La Vie de Jesus)

What's going on?

The labeling on DVDs isn't always clear, and so tends to involve a bit of guesswork, but my best effort at translating your examples would be:

"1.85:1 Widescreen" The original film was in 1.85, and this ratio has been preserved in the video. Whether the video is 4:3 considerably letterboxed or 16:9 slightly so isn't specified. There is a 'Letterbox' logo which is sometime used on the former format.

"1.78 Anamorphic" The word 'Anamorphic' means that the video is in 16:9 format, unless the recording has been mis-labeled of course. I couldn't remember the original aspect ratio of this film; IMDB says it is 1.85; if that is correct then from the wording, it has probably been cropped slightly to fit he video frame, though it is also possible that it has been slightly letterboxed to preserve its original ratio.

"Widescreen 2.35:1" The original film was 2.35. This description tells you nothing about the video format used on the DVD. In this case from what you say it sounds like an error (not uncommon) but if used correctly it should mean that the original ratio has been preserved by letterboxing within the video frame, which could be either 4:3 or 16:9.

"16:9 full height anamorphic" The video is in 16:9 format, and the image is not letterboxed. I don't know this film, or it's original format. It has probably been cropped slightly in one direction or the other if originally 1.66 or 1.85. Films which were originally shot on Super-16 fit the 16:9 frame almost exactly. Of course, this also applies to films shot on high-definition video. It is also possible that it means that the film is 1.85, and slightly letterboxed on the 16:9 frame, but much less so than if it had been on 4:3

"1.85:1 Anamorphic" 'Anamorphic' in this case tells you that the video format is 16:9; the 35mm 1.85 format is not anamorphic. The video should preserve the original ratio, and the picture will therefore be slightly letterboxed within the 16:9 frame.

'Anamorphic' in this case again in this case probably means 16:9 video, not the original film format. Of course, many 2.35 films are shot on Super-35, and are therefore non-anamorphic anyway. Since it says 2.35 this ratio should be preserved by letterboxing within the 16:9 video frame. In this case the black bars will be wider than in the previous example, due to the wider ratio.

As I said, the descriptions are not always clear; do my interpretations match what you actually see in each case. If you play the DVD on a computer, and set it to not play full screen then the border of the window will be in the aspect ratio of the video, 16:9 or 4:3, and the degree of letterboxing can be clearly seen.

Sorry about the long reply, but there's no simple answer.