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John_Pytlak
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Latitude

Post by John_Pytlak »

Those examples from Kodak demos certainly show the exposure range that color negative can accomodate in the scene, but the real advantage of color negative is the "latitude", where the overall exposure can be off by a few stops and still capture all the tonal detail in the scene.
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Re: Latitude

Post by Justin Lovell »

John_Pytlak wrote:Those examples from Kodak demos certainly show the exposure range that color negative can accomodate in the scene, but the real advantage of color negative is the "latitude", where the overall exposure can be off by a few stops and still capture all the tonal detail in the scene.
huh?

exposure range is just another word for latitude. please correct me.
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Re: Latitude

Post by John_Pytlak »

jusetan wrote:
John_Pytlak wrote:Those examples from Kodak demos certainly show the exposure range that color negative can accomodate in the scene, but the real advantage of color negative is the "latitude", where the overall exposure can be off by a few stops and still capture all the tonal detail in the scene.
huh?

exposure range is just another word for latitude. please correct me.
Not really, they are related, but different.

Exposure range usually refers to the range of tones that can be reproduced in the final image. For well projected images, this might be up to about 600:1 brightness ratio on screen, or about a 9 stop range.

Latitude measures how much you can overexpose or underexpose that exposure range, and still capture all the highlight and shadow detail, even if some adjustment needs to be made in printing or transfer.

The Kodak website has a good tutorial on tone reproduction:

http://www.kodak.com/US/en/motion/suppo ... ture.shtml

http://www.kodak.com/US/en/motion/suppo ... sure.shtml
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Post by Justin Lovell »

ah.

thanks for clarifying, had to reread it a few times to fully grasp what you were getting. Latitude in my head is kind of like 'pedestal'.
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Post by T-Scan »

Exposure range usually refers to the range of tones that can be reproduced in the final image. For well projected images, this might be up to about 600:1 brightness ratio on screen, or about a 9 stop range.
Now isn't most digital projection still far behind this range? I think about this whenever I hear hype surrounding digi projection in theaters, as if it has superior performance.
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Post by John_Pytlak »

T-Scan wrote:
Exposure range usually refers to the range of tones that can be reproduced in the final image. For well projected images, this might be up to about 600:1 brightness ratio on screen, or about a 9 stop range.
Now isn't most digital projection still far behind this range? I think about this whenever I hear hype surrounding digi projection in theaters, as if it has superior performance.
It depends on how you measure the "contrast ratio". Digital Cinema projection used for feature films has greatly improved contrast ratios compared to a few years ago. But 600:1 is about the best you can really do in a practical theatre (due to lens flare and stray light), even though a film print on Kodak VISION Premier Color Print Film 2393 can have a density range of almost 5.0 (or 100,000:1) between highlights and shadows.

I used to test the contrast ratio of Digital Cinema projectors at trade shows by "making shadow puppets" in areas of the projected image that were SUPPOSED to be black, and obviously weren't.
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Post by David M. Leugers »

I used to test the contrast ratio of Digital Cinema projectors at trade shows by "making shadow puppets" in areas of the projected image that were SUPPOSED to be black, and obviously weren't.
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Post by mattias »

digital projection is fantastic these days. the black level is the problem left to solve but in general it's at least as good as most prints, in my opinion.

/matt
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Post by Angus »

I don't often get to work with leading edge gear, but its only a month since I saw a top professional digital projection system close up...and I wasn't aware that it had reached the quality of film.
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Post by kentbulza »

Ummm...I guess I'm blind or I'm going to the wrong theatres. I still cringe at the 1920x1080 I see at the Arclight in Hollywood when I compare it to even 1.85 35mm. Although some of the 2K DI makes me cringe too! Are you guys going to 4K theatres or something?
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Post by mattias »

i do think you're going to the wrong theater, but in any case: it's not perfect but the point is it's been a long time since i saw a perfect 35mm print too.

/matt
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Kodak Digital Cinema

Post by John_Pytlak »

Certainly Digital Cinema projection is getting very good. Kodak has long advocated better digital cinema standards, such as 2K and 4K systems with higher "dark chip" contrast ratios, compared to the earlier 1280 x 1024 pixel projectors. Kodak engineers are very active participants on the SMPTE DC28 Digital Cinema standards committee.

Kodak technology (scanner used in Thomson Spirit DataCine) has been used to make many of the Digital Cinema Masters over the last 7 years. Kodak Laser Pacific is one of the major Digital Mastering facilities. Kodak is the leading independent supplier of digital pre-show entertainment systems, and supplies state-of-the-art servers, networking and service for Digital Cinema systems used for feature presentation:

http://www.kodak.com/go/dcinema
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Post by mattias »

perhap you could also develop a better system for distribution? :-) insanely expensive cartridges that are really just 2.5" ide drives with non standard connectors is just soooo 1996 or whatever.

/matt
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Post by filmamigo »

I saw the Kodak DC pre-show for the first time yesterday.

It is certainly the best looking pre-show I have seen, but it wasn't perfect.

For one thing, the content was of varying quality. The true high-def content looked quite nice, the scaled SD content looked terrible.

I was sitting there thinking about how, if all of the content was high-def, it might rival a film print.......... but I was wrong. After the pre-show, the 35mm trailers exploded onto the screen and I quickly forgot any thoughts of high-def projection. Seeing digital and film back to back like that was a good reminder of the impressive detail and latitude that 35 has. Those qualities aren't simply a technical concern -- they make an audience sit up, pay attention, and get lost in the films.
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Digital Cinema Distribution

Post by John_Pytlak »

mattias wrote:perhap you could also develop a better system for distribution? :-) insanely expensive cartridges that are really just 2.5" ide drives with non standard connectors is just soooo 1996 or whatever.

/matt
The media chosen for distribution of the Digital Cinema Distribution Masters (DCDM) is decided by the SMPTE DC28 Digital Cinema Committee, and obviously will change as new technologies evolve. It's likely the future will be by satellite or fiber, rather than physical media.
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