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Author Topic: Cyan Tracks John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 07-25-2003 09:56 AM                        jhawk asked: quote: do you have any information with regards to my query above about whether we are at 100% high magenta now? Almost every major release printing lab in the world offers "high magenta" tracks. In most cases, it's just a matter of changing the filtration of the lamp on the contact printer soundhead. But not all distributors have made the switch, so with the old (cyan + magenta + silver) analog tracks, the cross-mod distortion may only be optimized for one or the other type of reader: http://www.kodak.com/US/en/motion/support/sstLabs.shtml  |  IP: Logged Oscar Neundorfer Master Film Handler Posts: 275 From: Senoia, GA Registered: May 2000 posted 07-25-2003 02:17 PM                        Johm P. said: quote: the cross-mod distortion may only be optimized for one or the other type of reader I guess I just have too high a "density" factor regarding the cross mod problem. Maybe someone can explain it to me. As I understand it, obtaining good cross modulation cancellation is a matter of optimizing the negative soundtrack image density and the positive soundtrack image density so that the effects of image spread and image choking are effectively cancelled. Now if that is true, then I assume you end up with a low distortion soundtrack (and I am speaking of the distortion caused by the imaging process). SO... in theory, what difference does it make what light source is used to play back this low distortion track. (Of course I know that you have to have a red source for cyan tracks.) So for a conventional soundtrack, which can be played with a tungsten, IR, or red source, why does the cross modulation cancellation have to be optimized for a particular light source. I just don't understand why the light source matters here. Help please!!  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 07-25-2003 03:33 PM                        AFAIK, is has something to do with both the "image spread" of the reader optics, as well as what is in the film to modulate the light. With a red LED, all of the light is in a very narrow bandwidth near 660nm. So both the cyan dye and the silver can very effectively modulate the light, which is easily specified. With tungsten light, the light that needs to be modulated covers the entire visible and infrared spectrum, so the cyan, magenta, and silver all play a role in varying proportions across the spectrum. The overall "density" of the track will vary whether it is "seen" only in the red, or over the entire range of the tungsten spectrum. So, the "optimization density" in the cross-modulation test really does depend on the actual reader used, and not just on an arbitrary densitometer reading. The ideal densitometer and test equipment used to control cross-modulation should spectrally MATCH the reader in the projector. "High Magenta" was empirically found to optimize at nearly the same density for both type of readers. In theory, cyan dye tracks are likely to result in BETTER control of cross-mod optimization density for several reasons: 1. Almost ALL labs have a densitometer to read Status A RED density (some smaller ones still don't have IR densitometers). 2. The spectral characteristics of readers in theatres will be much more consistent, and easy to specify, as opposed the the mix that currently exists.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 07-25-2003 10:07 PM                     I know our print of THE HULK had a mix of high-magenta and conventional, depending on the reel! So some labs certainly are not using or always using high-magenta. Steve  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 07-25-2003 10:18 PM                        Different reels printed at different labs?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 07-26-2003 08:25 AM                     Gotta be! It would take effort to switch things about at the same lab. Steve  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 07-26-2003 12:30 PM                    Roughly speaking, how much brighter would an incandescent exciter bulb need to be if, filtered to red only (gel or dichroic), it is to give satisfactory output on a cyan track? Just wondering if something like that would be feasible for those who must run older prints but be compatible with new.  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 07-26-2003 03:14 PM                        I recall that Gordon McLeod discussed a tungsten lamp red reader available in Europe (Kinoton?). You are filtering out most of the energy produced by the lamp with the IR dichroic filter and any addtional red filter, so you'd have to have quite a bit of light (high wattage and heat) to begin with. I doubt it would be practical to simply filter an existing exciter lamp and still get enough pure red light. Dye-based filters usually pass IR, and are more prone to fade.  |  IP: Logged Jeffry L. Johnson Jedi Master Film Handler Posts: 809 From: Cleveland, Ohio, USA Registered: Apr 2000 posted 07-26-2003 05:46 PM                        The 2001 February issue of Scientific American has a cover story/special report about water. There is also an article about LEDs that does not appear to be on the Web site.  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 07-26-2003 07:30 PM                     The Kinoton halogen / dichoric module uses a halogen long life bulb which is superior to a typical exciter lamp.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 07-26-2003 07:48 PM                        How exactly are the SDDS and Dolby D tracks printed? They are dye-only, right? Aren't these read by a video method? Wasn't there a paper in the SMPTE Journal back long before the birth of cyan or high-magenta, which discussed an analog optical reader that was video-based? If I recall, the system scanned the analog track with a small CCD camera. At the time the system was not about different types of tracks, only about its accuracy as there was only the one conventional soundtrack, but I am guessing that using this method of capture, the make-up of the track would be irrelevent, be it redeveloped, high-magenta or cyan, as long as the camera could "see" it. If this assumption is correct, it would be THE system for art houses that play a mix of print types. I certainly wish I knew about all these issues BEFORE I listened to the industry's unqualified praise for the upgrade in performance that the red reader was supposed to afford, and I went out an purchased four Kelmar reverse scan/red exciters for two theatres. I would have at least opted for the BACP units had I known that IR exciters would give better performance for conventional tracks. When I first heard about the down side of the cyan initiative (right here on these very pages), I went to Kelmar and discovered that they still had plenty of IR exciters available. I may convert back to them, keeping the red in waiting for the first cyan track I encounter. Except for sneaks, all the titles we run are conventional tracks, so from what I've learned here, it would make sense to make the IR exciter the standard and swap it out for the red exciter only if and when we get a sneak that's got a cyan track. In the other theatre we never run anything but retrospective so IR would be ideal there. Anyone want to buy two Kelmar red exciters? BTW, the new print of CREATURE FROM THE BLACK LAGOON had a mix of tracks -- some reels were variable area and some were variable density -- all were high-magenta. Frank  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-26-2003 07:54 PM                     Ultra Stereo distributes a CCD based optical scanner that converts the analogue to digital and removes noise etc  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 07-26-2003 08:03 PM                     Gordon (or anyone), a link please for the USL product?  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 07-26-2003 08:51 PM                     The CCD reader was shown at a trade show in the early - middle 90's. It had a very high price for the market and according to Jack Cashin was destined for studio and screening situations....this was just before the LED reverse scan kits became popular...based on the spec information, it was and still probably state of the art for analog pickup.  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 07-27-2003 08:40 AM                        Frank: If those conventional (cyan+magenta+silver) prints had their cross-mod optimized for a red LED reader, that would be the best way to play them.  |  IP: Logged

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