posted 05-14-2004 05:57 AM                       

quote: Gordon McLeod

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Firstly SMPTE has no legal authority to mandate anything all they provide is prepare a volentary set of guidlines called standards

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posted 05-14-2004 07:59 AM                       

quote: William Hooper

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John: is there a SMPTE RP for XM distortion, & did silver tracks on red readers achieve its recommendation?

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quote:

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A conventional silver print, played back on a red LED reader, will not display the same crossmod cancellation characteristics as it would if it were reproduced on a standard tungsten reader. Figure 3 shows that a silver track read on a tungsten reader will display good crossmod cancellation when the negative employed to print the track has a density of 2.18 optical density units (O.D.). The same track needs to be printed from a negative with a 2.6-O.D. density if it is to display good crossmod cancellation when reproduced on a red LED reader.

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Fortunately, there is a sound negative density, in conjunction with a print color balance, that will produce a release print capable of playing equally well, in terms of crossmod cancellation on both tungsten and red LED readers. This print is called a "high-magenta" applicated print and requires a negative density of ~2.7 O.D. with a print color balance of 1.09 IR, 1.44 Y, 2.02 C, 3.82 M. Figure 4 shows the crossmod results from such a print.

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posted 05-17-2004 03:12 PM                       

quote: John Pytlak

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AFAIK, most prints made with cyan+magenta+silver tracks are currently being optimized for red LED readers.

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quote: John Pytlak

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I said "AFAIK", because I heard it second-hand. One of my fellow Kodak engineers visited one of the major sound houses in Hollywood. He noted that the cross-mod testing was mostly being done with red LED.

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I stand corrected --- cyan+magenta+silver tracks are normally optimized for white light or IR readers. I double checked with our Hollywood office, and they were told the following:

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...here is how we read the Xmod Tests

Silver Tracks - White or IR Reader

High Magenta - Red and IR Reader - Check for compatibility. If there is a difference we lean toward the cancellation for the RED Reader

Cyan - Red Reader

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quote:

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...this is how we are doing the XMOD tests. Silver tracks are only compatible with white or IR readers. Optimizing silver tracks for RED would be a painful experience in terms of educating the post and distribution community.

All of this nonsense regarding XMOD will obviously be much easier once there is cyan only printing worldwide. One track - one reader - simple.

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Moral of the story --- never trust your "fellow engineer" to get every detail right from just taking a tour of a lab. They were probably doing "high magenta" tracks at the time.

posted 05-18-2004 02:43 PM                       

quote:

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MGM First To Use Cyan Soundtracks On All Titles

LOS ANGELES – With the May 28 release of “Soul Plane,” MGM will become the first major motion picture distributor to release all of its titles in the environmentally friendly cyan-dye analog soundtrack format.

The move follows DreamWorks’ Sept. 19 release of the Jason Biggs-Christina Ricci romantic comedy “Anything Else,” the first feature to to be distributed exclusively on dye-only prints (In Focus, September 2003).

Cyan-dye-only soundtracks are produced without the caustic chemicals and silver used in the usual print manufacturing process and significantly reduce water usage. Silver-replicated tracks collectively use approximately 20 million gallons of water a year – enough drinking water for a town of 75,000. Distributors further reduce waste by eliminating the need to replace prints due to redevelopment problems in silver soundtracks.

“MGM is proud to be in the forefront of this landmark change in film soundtracks, and to be taking a significant step in improving the environment,” said Chris Aronson, MGM executive vice president and general sales manager.

Conversion to cyan requires the installation of red light-emitting diode (LED) readers in projectors, as a pure cyan soundtrack played on a white light or infrared reader will cause distortion, sound reduction or possible inaudibility. It is estimated that the vast majority of the projectors in the United States are now equipped with the red LED readers, according to an MGM press release.

The studio’s release of these prints marks a significant breakthrough in making the conversion to pure cyan a reality for NATO, which has worked closely with the Dye Track Committee, a group of motion picture executives formed in 1998, in the fight to replace silver tracks with pure cyan dye tracks.

LEDs also last about five times longer than tungsten lights, and slowly fade over time, giving operators warning that replacement is due.

“We are grateful for MGM’s leadership, and delighted that the studios are taking advantage of the theatres’ shift to red-light readers,” said NATO president John Fithian. “This demonstrates that the film industry as a whole has an environmental conscience.”

Digital soundtracks do not require silver replication and are thus not affected by the new process.

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posted 05-19-2004 01:54 AM                       

quote: John Pytlak

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SMPTE Recommended Practice RP104 specifies XM distortion measurements

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quote: John Pytlak

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...this is how we are doing the XMOD tests. Silver tracks are only compatible with white or IR readers. Optimizing silver tracks for RED would be a painful experience in terms of educating the post and distribution community.

All of this nonsense regarding XMOD will obviously be much easier once there is cyan only printing worldwide. One track - one reader - simple.

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posted 05-19-2004 06:25 AM                       

quote: William Hooper

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Since the "one track" part of the above is erroneous, at what point should there be an expectation of silver tracks optimized for red readers?

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posted 05-19-2004 10:08 AM                       

quote:

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This document has been divided into several sections to maintain simplicity and to separate the functional and hardware segments from the theories of cross-modulation testing....If a negative containing both music and voice passages is printed onto a print film at several different densities over the range from 1.0 to 1.6, the average listener may find the quality of music fairly acceptable over the whole range. Some of the voice passages, however, will contain an excessive amount of sibilant distortion.1 That is, many of the sibilant speech sounds (s, sh, ch, z, etc.) and some of the voiced and voiceless stop sounds (B, P, and T) will be distorted and spitty.

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posted 05-20-2004 06:17 AM                       

quote: William Hooper was the last to post

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...this is how we are doing the XMOD tests. Silver tracks are only compatible with white or IR readers. Optimizing silver tracks for RED would be a painful experience in terms of educating the post and distribution community.

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