For Ken Ross & Others: Standards/Fidelity/Intent, Etc.
Ken,
I have been dwelling upon your questions in this thread for days. To answer each one in detail would be too tedious for this format. Here is my attempt to generally corral the major issues into some semblance of order and theme. Handling all the potential details in a manner that attempts to avoid further questions would more appropriately be a thread all its own. The root of this challenge has to do with not knowing what fundamental principles of motion imaging reproduction you already understand. That's a problem encountered in hobbyist forums regularly. The average videophile consumer simply has not had formal, structured training, but all too often a sparse or random mishmash of familiarity with essential fundamentals.
You have asked about "standards." Strictly speaking, motion imaging industry standards bodies publish standards documents, engineering guidelines, recommended practices, and registered disclosure documents to guide the industry in how to do what they do in a unified way. Here is a link to the complete index of SMPTE publications:
https://www.smpte.org/sites/default/files/Standards-Index_07-09-2012.pdf . You may gain some degree of understanding of how all these publications differ by type from reading the titles. If you see a topic that interests you, perhaps you would want to purchase the document from SMPTE for personal study.
Contrast ratio, or dynamic range, is not specified in any standard that I know of. There is discussion of minimum specifications and tolerances in certain recommended practice publications. Here are some examples I located from my limited library:
Recommendation ITU-R BT.710-4, 'Subjective Assessment Methods For Image Quality In High-Definition Television'
Ratio of the luminance of the screen when displaying only black level in a completely dark room, to that corresponding to peak white- ~ 0.01 [100:1]
'Color Processing for Digital Cinema 4: Measurements and Tolerances' SMPTE Journal, July 2007, based upon SMPTE Engineering Guideline 432-1 (also in
'Digital Cinema System Specification' version 1.2, Digital Cinema Initiatives, LLC, March 7, 2008)
Sequential Contrast:
Theoretical Reference: 2000:1 Minimum
Review Room Tolerances: 1500:1 Minimum
Theater Tolerances: 1200:1 Minimum
Intra-frame Contrast:
Theoretical Reference: 150:1 Minimum
Review Room Tolerances: 100:1 Minimum
Theater Tolerances: 100:1 Minimum
EBU-Tech 3320, 'User Requirements For Video Monitors In Television Production' May, 2008
Full screen (1% patch) contrast ratio shall be [1% white window on a black screen?]:
Grade 1 Monitor: above 1000 to 1
Simultaneous contrast ratio (with EBU box pattern) should be [similar to ANSI checkerboard?]:
Grade 1 Monitor: above 200 to 1
'Picture Rendering, Image State, And BT.709' Charles Poynton, April 29, 2009
"Today’s studio reference displays have gamma very close to 2.4, reference white luminance of between 80 and 120 cd·m-2, and a contrast ratio of about 100:1. They are viewed with a dim surround, illuminated such that the surround luminance is about 5% of the reference white luminance."
Essentially, content producers expect there to be some variation in contrast when viewing their work, depending on the type of display system being used. It is understood in the professional imaging world that contrast should be maximized where possible. There are limits to how much brightness the human visual system can tolerate, so the preferred method for optimizing contrast is to lower the black level. The ideal would be black at zero luminance, which would mean a contrast ratio of infinity, independent of peak luminance achieved.
Regarding "artist's intent" versus "reality" in electronic imaging, here is a pertinent quote from a leading industry expert:
"The goal of video production is not to reproduce, at the viewer’s premises, an accurate representation of the scene in front of the camera. Rather, the goal is to reproduce an accurate representation of what the director saw on his studio display upon approving the final product of post-production. Image data modifications are imposed for creative purposes at various stages of professional video production. Whatever image processing operations were used to create the final image – whether physically meaningful or not – are fair game." 'Picture Rendering, Image State, And BT.709' Charles Poynton, April 29.2009
Regarding the so-called "soap opera effect" resulting from certain frame interpolation schemes: it is an unintended consequence of attempting to solve or mitigate motion rendering deficiencies inherent in LCD display technology. It is simply a new type of image distortion that can dramatically alter the "look" of video programs.
Film-based programs offer their own unique characteristics that may not translate fully to the video domain. Horizontal pans are a good example. The 3:2 pull down motion artifact evident in 30/60Hz video frame conversion drives film people crazy to watch. Using even multiples of 24fps solves this problem but doesn't produce unintended consequences if implemented cleanly. Digital Cinema programs can be produced with 24fps digital cameras, higher bit rates, and wider color gamut. Converting such motion picture programs to consumer video is understood by the artist to require changes to the "look" of the program. It is difficult for an average videophile consumer to be aware of the nature of what potential changes may be tolerated and what ones are not by the cinematic artist community. I don't have an answer to that, other than seeking the guidance of someone trained and skilled in reference imaging.
Best regards and beautiful pictures,
Alan Brown, President
CinemaQuest, Inc.
A Lion AV Consultants affiliate
"Advancing the art and science of electronic imaging"