Is Blu-ray good enough for theatrical use?

[rwobrien]

Hello, All,

I am the tech dir for an independent film festival. We all know how good Bluray looks on fairly large screens, but how does it play on really big screens...up to 70 ft? Does compression artifacting become visible? How would it compare to say, BetaSP or DigiBeta output?

What are other issues to consider? What is the best output to use DVI or HDMI? Are there any Bluray decks that put out SDI?

Thanks!

[Beta Man]

You'd want to output with HDMI....

and as far as how it would work with 70' screens, that would depend on the projector you're using.

I assume you're budgeting at least $100,000 for the projector....

All artifacting etc. depends on the projector you get at that point....

I wouldn't use Blu-ray for a 70' screen... I'd use film.

[rwobrien]

The projectors used would be very high end. , such as the NEC STARUS NC2500S. There would be lesser ones as well...but all in regular use at a high-end movie house.

I was just concerned that, being a consumer format, Bluray may not hold up when blown up to theatrical sized screens.....

We have been using BetaSP and DBeta in the past. Would this be a step up, down or lateral?

Thanks

[Beta Man]

Wouldn't movies be available to you on Film LONG before they are ever pressed on a Blu-ray disk though??? I just don't think using Blu-ray is your best option, since it's a transfer from the original source material, and you could be using the source directly.

[rwobrien]

Actually, we would always accomodate a filmmaker's submission of 35mm, but we found that over 90% of last year's submissions were on BetaSP or DBeta.

Very few indy filmmakers can afford to shoot in 35mm ...or even 16mm for that matter. They usually use DVCAM or even HDV these days....so to ask them to burn to Bluray for submission would be a convenient option for all.

It costs me $500/day to rent each DBeta deck. Thats 3 screens for 4 days. Methinks I'd rather buy a few Bluray decks so long as they deliver the goods.

[Beta Man]

if the projector you already have can accommodate a blu-ray player, I'd just connect one for a quick comparison. Your equipment and "usage" are far beyond my level of knowledge (which is minimal)

[WriteSimply]

From D-Cinema Today:

2K is the term used to describe images that have approximately 2K vertical lines. In digital cinema, a 2K image is delivered to the theatre in a digital "container" 2048 pixels wide by 1080 pixels high. A 2K image with a 2.39:1 ("scope") aspect ratio could be supplied having 2048 x 858 pixels. A 2K image with a 1.85:1 ("flat") aspect ratio could be supplied having 1998 x 1080 pixels. 2K resolution is specified by DCI as the minimum needed for showing theatrical content.

So BD "lose" 78 pixels for 1.85:1 films. How does it look like at 70 feet? Not sure.


fuad

[Chevypower]

Originally Posted by rwobrien

I was just concerned that, being a consumer format, Bluray may not hold up when blown up to theatrical sized screens.....

We have been using BetaSP and DBeta in the past. Would this be a step up, down or lateral?

Thanks

It would be quite a step up to Blu Ray quality. BetaSP was a stable wide-band analog standard def format with a YUV component signal. Fast tape speed and 1/2inch tape made it robust. It had the 480x720 or 576x720 limitations, and PAL/NTSC color burst limitations.
Digital Betacam was similar, but it was recorded digitally. 4ch PCM sound, Video was digital at 90mbs recorded in 4:2:2. Same 480x720 or 576x720 and normal PAL/NTSC 3.58mhz and 4.43mhz colorbursts. It would look stable and smooth on a large screen, but not high enough in definition compared to Blu.

XDCAM HD/EX and HDCAM/SR will be suitable broadcast formats for Blu Ray. HD formats (including Blu-Ray) do not have any colorburst subcarrier limitations.

[rwobrien]

This is the sort of info that I've been looking for!

Thanks to all of you.

So...has anyone actually put their eyes on Bluray on a theatrical-sized screen? Does the data really translate to such great quality?

[Blu Titan]

Deci had a really good post about the subject a while back, but I can remember the technical details.

[Deciazulado]

The main difference between 16:9 2K Digital Cinema and 16:9 Blu-ray is the compression.

The ITU papers claim that on their tests, screen resolution from actual 35mm film projected averages less than 700 lines per picture height.

When I ran the SMPTE RP-40 laboratory test film, much sharper than any real life test image (80% MTF at 160 l/mm), many projectors showed less than 1100 lines


Maybe Blu Titan is refering to this post I made about pixels at 2K scanning? :

2K normally means a 2048 pixel scan across the silent 35mm Frame width designed to cover almost the Full 35mm Camera Aperture* for a total file size of 1556 x 2048 pixels (height x width) at around 83.33 pixels per mm (2117 dpi) covering an area of aproximately 18.672 mm by 24.576 mm (0.735" x 0.968") which is more than enough for the intended area to be shown (the Projector Aperture) of all 35mm formats:


1.33:1 Silent 35mm projection frame: 0.710" x 0.945" = 1500 x 2000

1.37:1 Academy Sound 35mm projection frame: 0.600" x 0.825" = 1270 x 1746

1.66:1 European 35mm projection frame: 0.497" x 0.825" = 1052 x 1746

1.75:1 Disney 35mm projection frame: 0.471" x 0.825" = 996 x 1746

1.85:1 US 35mm projection frame: 0.446" x 0.825" = 944 x 1746

2.39:1 Anamorphic 35mm projection frame: 0.690" x 0.825" (current digital) = 1460 x 1746

2.39:1 Anamorphic 35mm projection frame: 0.700" x 0.838" (revised optical) = 1482 x 1774

2.35:1 Anamorphic 35mm projection frame: 0.715" x 0.839" (original optical) = 1512 x 1776

2.55:1 Anamorphic 35mm projection frame: 0.715" x 0.912" (original magnetic) = 1512 x 1930

1.85:1 Super 35 Panavision extraction for flat prints: 0.511" x 0.945" = 1080 x 2000

1.85:1 Super 35 Arri DIN extraction for flat prints: 0.500" x 0.925" = 1060 x 1960

2.39:1 Super 35 Panavision extraction for anamorphic prints: 0.395" x 0.945" = 836 x 2000

2.35:1 Super 35 Arri DIN extraction for anamorphic prints: 0.394" x 0.925" = 832 x 1960



1.33 *Full Camera Aperture: 0.735" x 0.980"

[wiredmass]

If you're going to project that large of an image from blu, you must buy a flux capacitor.

[ToEhrIsHuman]

Most digital DLP houses in the U.S. are still 2K, though the occasional 4K projector is used. I've seen 2K projection in a theater with a larger screen than what you propose and it was certainly adequate. I've also read that current release 35mm prints usually aren't much better quality than upscaled standard def for whatever that's worth. I say go for it, and for myself I have to figure out how to score that setup for my backyard.

[Joe Cain]

This might be relevant to the discussion:

As we were welcomed to the event by Panasonic Vice President of Corporate Development and General Manager of the Blu-ray Disc Group, Eisuke Tsuyuzaki, and introduced to many visiting executives, a beautiful 2k projection of Fantastic Four: Rise of the Silver Surfer was put up on the massive [one hundred foot] screen. As the introductions were completed it was announced that what we had actually been viewing was a split-screen presentation where one half of the picture was the 2k master and the other half was directly from the Blu-ray version of the film. To our astonishment, not a single attendee was able to correctly guess which side was which.

Posted in the News section last year. As the author, perhaps Ben might be able to offer more details on the presentation?