Originally Posted by dovercat
According to "Color and Mastering for Digital Cinema" by Glenn Kennel
Vision Color Print Film 2383 has a density of 3.2
Vision Premier Color Print Film has a density of approximately 3.6
Glenn Kennel worked for Kodak until 2003 when he left to be a consultant on DCI cinema and boasts an impressive resume and accolades, so I am going to assume he is right.
Until 2002 when Dr. Rodger Morton of Kodak's R&D team posted a journal article film is usually rated up to a density of 4.0 which is over 8,000:1.
But film can actually do a physical maximum of ~20 stops or ~6.0 density.
Which is why a rep for Kodak said their film prints of Minority Report were approximately 10,000:1 dynamic range. Which is already proving what I said of 3,000:1 being a conservative number of what film is capable of.
I don't understand why you're arguing when I said 3,000:1, which is below the 3,981:1 of what you said your source said. Which also confirms what my source Alan Gouger said too. Maybe his print wasn't one of the most pristine, or his measurement environment wasn't ideal.
My point was film can easily exceed well over 3,000:1, which again is well over the 1400:1.
What were we arguing again?
Oh yeah! I remember. 836:1 of the BenQ contrast royally sucks and is pathetic. Not to say that's BenQ's fault, what they made is amazing. The fault lies in TI's 4K DMDs which have horrid contrast which was beat about ~20 years ago!
Also, that means no matter how much BenQ tries to hide their "disappointing contrast," even if they clamp down on the iris, then nothing on the screen is the maximum brightness. Which means, at no time is there an instantaneous contrast over 836:1.
What you need to do is clamp down the iris, then measure, and then fully open the iris and measure again.
Kodak image scientist Dr. Roger Morton and his team published a technical paper "Assessing the Quality of Motion Picture Systems from Scene-to-Digital Data" in the February/March 2002 issue of the SMPTE Journal (Volume 111, No. 2, pp. 85-96).
The analysis of dynamic range was done by a special test scene using various shiny metallic spheres reflecting specular highlights to evaluate the dynamic highlight range above an 18% gray. The film tested was Kodak VISION 500T Color Negative Film 5279. The data showed the "Dynamic Highlight Range of 18% Gray" was 15.9 stops. In other words, the film was able to record detail in highlights as much as 15.9 stops above a normal 18% gray card exposure, plus darker scene elements 3.3 stops below an 18% gray (Figure 16 in the paper). The paper concludes "Thus, real world scenes can produce 20 stops of dynamic range, or an intensity range of about 1,000,000:1". The published paper details how the test was conducted, and has scanned images showing the results of the test.
Kodak normally evaluates color negative film sensitometry over a 4.0 log exposure range (about 13 stops). Dr. Morton's test was part of an evaluation that took film to the limit in a practical scene, with super-highlight specular reflections in metal spheres that went well beyond the normal 13 stop range routinely evaluated. By routine sensitometric measurements (4.0 log exposure), the new VISION2 films generally have better latitude and linearity than the older generation of films. But you would be extrapolating to say what was happening with another 7 stops of exposure. I'm sure the new Kodak VISION2 films will be included in any future work by the team that wrote the 2002 SMPTE paper.