DCP at 1.9:1 (Full Container) Projection

[Robert Cauble]

Do cinemas accomodate actually screening the 2048x1080 (2K) and 4096x2160 (4K) DCP formats? This is the standard that is referred to as full container (S) as it is the maximum height and width of the DCP container. A couple projectionists have told me that the projectors only allows for scope (2.35) and flat (1.85) projection, but the option is always given to deliver full container.

 

[Garrett Sergeant]

Not really. To be DCI compliant, a projector needs to have a minimum resolution of 2048x1080.

 

[Patrick Tresch]

Are there 2 defferent things?

The container resolution 2048x1080
The projecting lens (1.85 lens or 2.39 lens format)

I'm not sure but I would love to know. How is 2.35 or 2.39 made from a 2k/4K dcp?
Is it cropped from the 2048x1080 container (2048x860pixels) and then blown up optically to the whole width or the screen? Or is the 2.39 projected in the 1.85 width without using any different optic or zoom? (This would mean letterbox).

Pat

 

[Ian Vertovec]

Are there 2 defferent things?

The container resolution 2048x1080
The projecting lens (1.85 lens or 2.39 lens format)

I'm not sure but I would love to know. How is 2.35 or 2.39 made from a 2k/4K dcp?
Is it cropped from the 2048x1080 container (2048x860pixels) and then blown up optically to the whole width or the screen? Or is the 2.39 projected in the 1.85 width without using any different optic or zoom? (This would mean letterbox).

Pat

DCPs you see in the theater are not actually 2048x1080. That is just the resolution a projector needs to be dci compliment. Theatrical DCPs are 1998x1080 or 3996x2160 for 1.85 & 2048x858 or 4096x1716 for 2.39.

 

[Robert Cauble]

Thanks Ian. Do you know why there is a delivery format spec for full container? Also how is a full container file treated during projection?

 

[Ian Vertovec]

I'm not really sure why it exists. I suppose it exists because it's relatively easy too create with the available tools. I would recommend. Exhibitors aren't really expecting such a thing, so they would probably just display it using the 1.85 preset.

You can read the entire spec at www.dcimovies.com

 

[Patrick Tresch]

DCPs you see in the theater are not actually 2048x1080. That is just the resolution a projector needs to be dci compliment. Theatrical DCPs are 1998x1080 or 3996x2160 for 1.85 & 2048x858 or 4096x1716 for 2.39.

I understand that, but the question is : how do they project 2048x858 (1:2.39) on a larger screen than the 1:85? Porjectors that project 2:39 have to use an optical zoom to make use of the whole screen to go from the 1.85 to the 2.39 format? Is this the way and there fore there are 2 different formats/projector settings. Otherwise the 2.39 woud be shown with lettre box (smaller portion of the screen than the 1.85 format).

Hope I'm clear...

Thanks.

Pat

 

[David Rasberry]

The projector displays the file you send it at the resolution of the file. If you send it 2048x1080, it will display it. If the screen is masked for 1.85:1 it would just over scan onto the mask border.
There are blanking adjustments that can mask the projector output window to 1998 but I don't think they are typically set up that way. The source file determines the blanking.

 

[Patrick Tresch]

So Scope would look tiny (letter boxed) on a big screen?

Pat

 

[Ian Vertovec]

Patrick,

I'm not sure I understand your question, but in order to screen both 1.85 and 2.39 in the same theater, optical zooming is usually done on the lens. Then masking (ie black curtains) fly in to conceal any areas of the screen that don't have picture projected. Barco's and Sony's usually have 1 push presets that automate color space, resolution, zoom, and focus.

Ian