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Topic: Screen: Common Height or Common Width?

Brad Miller
Administrator

Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99

posted 04-30-2015 07:53 PM

Actually Mike masking DOES affect the image. It improves it because it helps to cut down on reflected light...especially if the screen is curved.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-30-2015 09:39 PM

quote: Brad Miller
It improves it because it helps to cut down on reflected light...especially if the screen is curved.

Why I, and I bet a host of other members in this forum agree that we dislike the new practice of open masking on a 'scope image, being dead center of the screen, where the ambient light from the image(and even the 'black light' from the chipset) is filling this unused portion of the screen.

Just looks so tacky of all of that unused screen acreage with a picture only occupying some of that acreage.

The screen seems that it's begging to be masked to give that deserved scope presentation.

I like it when I do get to play flat DCP content, for at least, the screen is filled to capacity.

-Monte

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Bobby Henderson
"Ask me about Trajan."

Posts: 10973
From: Lawton, OK, USA
Registered: Apr 2001

posted 04-30-2015 10:20 PM

quote: Terry Lynn-Stevens
The current scope/flat digital set up is the ideal compromise for all parties involved. I doubt most customers will see the benefit from an anamorphic set up, and I say that because customers just don't seem to care that masking is been eliminated. So I doubt an anamorphic set up is going to do any justice.

I'll provide a visual image to show why the statement above is either trolling or just ignorantly stupid.

This is a proportionately accurate size comparison between the current DCP standard for 2K 'scope (2048 X 858) and what 2K 'scope really should be, a full frame 2048 X 1080 anamorphic enhanced image originally 2560 X 1080 in size.

The full frame anamorphic 'scope image is over 150% the size of the standard DCP 'scope image. That's a pretty freaking substantial difference. The 2560 X 1080 imagery used to encode the anamorphic image has over 1 million more pixels than the standard 2048 X 858 frame. 2764800 versus only 1757184. The full frame 2040 X 1080 imager chip has 2211840 pixels. Standard DCP scope omits 454656 of those pixels to arrive at its cropped bullshit scope image.

This is basically just like the differences between anamorphic enhanced DVDs and non anamorphic DVDs. I can actually watch an old 16x9 enhanced DVD on my 65" HDTV set and not be too badly bothered by the resolution limitations. The non-anamorphic DVDs I have, such as True Lies and The Abyss are totally unwatchable.

This anamorphic approach in d-cinema would make a big difference with image quality. But it takes both Hollywood studios creating DCPs with anamorphic enhanced content AND theaters outfitted with projectors using anamorphic 1.25x lenses to get the benefit.

With so many movies being created in 'scope format I might even go so far as to say the anamorphic approach should be used even in a single lens situation. Not many movies are made in 1.85:1. I don't think they would suffer too badly with the anamorphic treatment. Scope just needs to be the best quality format, not flat.

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Mike Blakesley
Film God

Posts: 12767
From: Forsyth, Montana
Registered: Jun 99

posted 04-30-2015 11:17 PM

quote: Terry Lynn-Stevens
What I don't understand is that you don't have masking yourself? You would think that someone like yourself would have it, but then again you also said that nobody has ever complained.

We DO have masking, it just doesn't move. Our screen is 2:1 and we run the scope picture to fill the screen, with the flat picture pillarboxed. It's been that way here since 1953.

When we first went to digital we set up the scope image so that it was slightly letterboxed, but I do agree with Brad that it makes the picture contrast seem better when there is no white screen, so we changed back to the 2:1 format. If the movie has content that needs the entire 2.39:1 frame (such as the recent "Frozen" short did), we run the movie with the slightly-letterboxed setting.

I would love to have moving masking but the way our screen area is set up I have no idea how many thousands of dollars that would cost.

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Gary Lightfoot
Film Handler

Posts: 20
From: Caterham, Surrey, UK
Registered: Apr 2015

posted 05-01-2015 03:59 PM

Do any/all current DCI projectors have the facility to stretch the 2048 x 856 scope image to fill the full 1080 height and use a 1.25 anamorphic lens to restore the geometry to 2.37?

Gary

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Bobby Henderson
"Ask me about Trajan."

Posts: 10973
From: Lawton, OK, USA
Registered: Apr 2001

posted 05-01-2015 05:43 PM

IIRC some can do that. The end result would be more efficient light spread. However, it isn't any better than zooming from an image resolution standpoint since it is still starting out with a lower resolution 2048 X 858 image. It would be FAR better is the projected image was an anamorphically authored, full frame 2048 X 1080 image. Movie studios need to render their 2K masters at 2560 X 1080 and when authoring to DCP compress them into an anamorphic 2048 X 1080 container.

By the way, 2560 X 1080 is a standard resolution that is supported by a lot of modern computer video cards. There are 21:9 computer monitors sold at 2560 X 1080 hardware resolution. That actually raises a point for future consumer video format standards. The electronics industry is seeing diminishing returns on a lot of new HDTV sets. Maybe they need to go wider from 16:9 to 21:9 ratio.

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Frank Cox
Film God

Posts: 2234
From: Melville Saskatchewan Canada
Registered: Apr 2011

posted 05-01-2015 06:44 PM

I don't have movable masking on my screen; it's a "perfect" scope screen and flat movies are centered with a foot or so of dead space on each side. It looks ok to me.

However, I always had the idea that if I ever wanted to put in movable masking, I could purchase some tracks like what you use for sliding closet doors. Build some tall "doors" to put into those tracks, wrap 'em with black masking cloth material, and that would be all that would be required. Slide them into place when needed, slide them back when not required. It wouldn't be automated, but so what? In my case (and Mike's, I would imagine) I'm only playing one movie at a time 99% of the time anyway so once I had the masking set I would be set for the week anyway.

I can't see that solution costing more than a couple of hundred dollars and a couple of days of construction work (since I'm not particularly good at construction). But I haven't actually bothered to do it, so far.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 05-01-2015 06:44 PM

quote: Mike Blakesley
I would love to have moving masking but the way our screen area is set up I have no idea how many thousands of dollars that would cost.

One could almost make their own masking..with the image scaled down to the proper ratio, move the image up to meet the top of the masking edge, then make your own width masking to go across the bottom of the screen to meet the bottom of the image.

Easily removable for flat presentations.

Where Mike has the long throw and small screen, the slight lines from the first three rows shouldn't be too affected by raising the image up a couple of feet.

-Monte

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Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

posted 05-02-2015 02:09 AM

ALL DLP based projectors can handle the anamorphic lens. The scaling technology is on the TI side of things (both series 1 and series 2 projectors). So even if you have say a Barco DP2K-20C projector that doesn't show the anamorphic settings, you can use the TI ICP/Enigma program to make a SCREEN file with the anamorphic squeeze that the Barco projector will happily recall like any other.

As Bobby notes, using an anamorphic with current content does not buy you any resolution. However it does buy you 23% more light (with the other 3% loss in the glass). Ideally it would have be a 1.26x anamorphic but I'm sure if tested a 26% stretch would have shown significantly more scaling artifacts than 25% hence it is just under ideal. That 23%, however, can normally mean a lamp size difference to hit your light on "Scope." Zooming the lens just wastes the light. If you read other threads, you'll find discussions where people have taken to setting scope's light level in the 11-12fL range and the Flat's light level in the 16-17fL range so the lamp is not ping-ponged between near minimum and near maximum level trying to balance both. With an anamorphic, that range is cut in half. Depending on the screen size, projector and lamp, you can have both target the standard 14fL or reduce the spread to something like 15fL and 13fL without stressing the lamp. In larger lamp situations, dropping the lamp size can really add up (particularly the 4500-watt and larger lamps). I suspect even with lasers it will provide a significant cost savings as a smaller laser system could be used. The scope format being the determining factor on how much projector one needs.

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Daniel Schulz
Master Film Handler

Posts: 387
From: Los Angeles, CA USA
Registered: Sep 2003

posted 05-02-2015 09:53 AM

quote: Bobby Henderson
This anamorphic approach in d-cinema would make a big difference with image quality. But it takes both Hollywood studios creating DCPs with anamorphic enhanced content AND theaters outfitted with projectors using anamorphic 1.25x lenses to get the benefit.

If I could change anything about the DCI standards it would be this. I miss real widescreen. Unfortunately the loss of resolution happens relatively early post production - even if the image is captured at camera with an anamorphic lens, typically the work files for editing and color correction, and definitely the DI, are 2048 x 858.

There is a company called Folded Space (a division of Panamorph, who make anamorphic lenses for home theatre projectors), who have developed a technology to create anamorphic widescreen Blu Rays that are backwards compatible with non-anamorphic playback. Essentially they take the extra pixel data, place it in the space normally occupied by the black letter boxing bars, and then use the Java in the Blu Ray standard to hide those pixels. If you have an anamorphic system, the Blu Ray player reincorporates the extra pixels, creating a 1920x1080 anamorphic squeezed image, which yields a true widescreen image upon projection. Folded Space has been hoping to get this technology adopted in Blu Ray and the proposed UHD Blu Ray, but I see no technical reason it couldn't be used in Digital Cinema as well.

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Lyle Romer
Phenomenal Film Handler

Posts: 1400
From: Davie, FL, USA
Registered: May 2002

posted 05-02-2015 10:45 AM

What makes Bobby's 1.25x anamorphically enhanced idea even better is that when applied to 4k, it makes it a 5k image. It can then be marketed as "Ultravision 5k" or something like that. It would be an image upgrade and a marketing upgrade for very little cost.

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Daniel Schulz
Master Film Handler

Posts: 387
From: Los Angeles, CA USA
Registered: Sep 2003

posted 05-02-2015 11:49 AM

quote: Lyle Romer
What makes Bobby's 1.25x anamorphically enhanced idea even better is that when applied to 4k, it makes it a 5k image. It can then be marketed as "Ultravision 5k" or something like that. It would be an image upgrade and a marketing upgrade for very little cost.

Agreed 100%. And it's not as though cinemas aren't casting about looking for something to differentiate themselves from home theatre...

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Gary Lightfoot
Film Handler

Posts: 20
From: Caterham, Surrey, UK
Registered: Apr 2015

posted 05-04-2015 06:32 AM

I've been using anamorphic lenses for over 10 years in my home theatre (Primsasonic and now ISCO), and although the source resolution does not change, scaling does produce a visibly better image than when zoomed from where I sit.

At home, we zoom 33% (rather than 25% for 2k), which is like moving your seating 33% closer, and pixels become more 'chunky' compared to a scaled image that is using more pixels which are smaller. The image looks more detailed and sharper despite the source res being no different than when zoomed. It all depends on how good the scaling is, and these days it's usually very good - no visible artefacts unless you use a test pattern. Much of this depends on how close you sit of course, and that is an important factor, more so than physical screen size.

I've been watching folded space (John Schuerman) over on avsforum but somehow I don't think it's going to happen unfortunately. [Frown]

It looks like 4k is going to be installed (and then 8k) before folded space gets used. At home, constant image height is a niche within a niche (of people with projectors), and if the commercial market is shying away from ananmorphics I can't see them wanting to go for folded space over a more marketable 4k, especially where the 4k zoomed pixels are going to be smaller than the pixels of a 2k image using anamorphics. IMHO.

Zooming doesn't always lose you a huge amount of light with home cinema projectors, but it depends where in the throw the pj is - when you zoom the prime lens to make the image larger, due to the way the lens elements re-arrange, the F-stop changes and you often find that as you zoom larger, you get more lumens and less on/off contrast. When you zoom smaller the opposite happens. In some cases the difference between zooming and using an A lens can be small and inconsequential. I'm guessing that with commercial installs, the set up and choice of prime lens means that is never the case.

I'm a huge fan of constant image height and hate the way modern multiplexes are just like big tv now. Most cinema goers have no idea about constant width or constant height so don't know what they are missing. Looking at documents from people like SMPTE, THX, Dolby etc, they seem to actively promote constant height in preference over constant width (and no mention of other compromise formats like constant area), yet the commercial part of the industry is (obviously I guess) more concerned with the costs of things rather than the art of presentation. If the advantage of a $10k anamorphic lens is lost on 99.99% of the cinema going public, I can see why no one wants to spend that amount of money on one.

Would I be right in saying that due to the loss of people like yourselves in the industry, they now need projector operation etc to be so simple that an untrained guy like a multiplex manager or the guy who sells the tickets and popcorn can click a mouse and start a movie? If that's the case, I can see that zooming an image for scope or trying to implement an anamorphic lens would just be too tricky and lead to problems.

I'm purely a home cinema enthusiast but have popped over here to see what your guys take is on various aspects, and how things are done in the commercial space. Hope you don't mind me throwing in my own perspective and asking dumb questions.

Please be gentle with me. [Smile]

Thanks

Gary

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Marcel Birgelen
Film God

Posts: 3357
From: Maastricht, Limburg, Netherlands
Registered: Feb 2012

posted 05-04-2015 07:36 AM

Scope in DCI should have been anamorphic right from the get go. The pre-DCI 1.3K machines like the DP-50 used anamorphics for scope with non-square pixels in the digital source files and DCI should have gone this same route.

It's just a blatant cost cutting measure that a format that's supposed to be LARGER than flat has to cope with less resolution and less light than flat...

So, anamorphic lenses and non-square pixels should have been a mandatory part of the DCI specs. The fact that we accepted a lesser thing is yet another example of what happens if we let compromises rule the industry.

And it's not just this thing, it's the composite of all those "compromises" what makes cinema what it is today and why, if we all happily continue on this path, we'll finally destroy the industry along with it.

If going to the theater adds nothing but frustration, people will just not go, movie studios will start releasing their features day and date with the streaming and rental market and that will be the end of it...

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Buck Wilson
Jedi Master Film Handler

Posts: 894
From: St. Joseph MO, USA
Registered: Sep 2010

posted 05-04-2015 03:04 PM

What would need to happen to make that change?

Or does it even matter with laser coming into the picture?

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