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Posted by Donny Miner (Member # 1590) on 02-21-2003, 03:56 AM:
 
I attended the Dolby Digital Workshop in San francisco on febuary 11th and they said by this time next year that almost every studio will be sending out 100% cyan prints. And that you must have a LED reader to read the prints and that the (white) lamps will not do. Has everyone changed or will be changing over to the LED's in the near future? ...Or do you think that the change will take a little longer than expected...Like maybe a few more years down the road?
We have NO LED readers at 6-screen theatre, but might be up-grading to the LED's in the near future. I think it might be a wise thing to do just in case they do the 100% cyan changeover and you won't be caught with a print that you can't play 'cause you dont have a LED reader.
I hear that the LED's have less noise than the (white) lamps and that the sound is even better...So why not do the changeover anyways? Does it cost a lot to buy/install the LED readers? Or is it something else? I guess that the studios been warning about the change for years now and that everyone should be or just about done switching over to the LED's.
Whats your thought on the 100% cyan changeover???
 

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Posted by Steve Kraus (Member # 476) on 02-21-2003, 07:41 AM:
 
Welcome, Donny. The alleged cyan conversion has been the subject of much debate here and if you use the search feature to look for "cyan tracks" you can find much of it.

Note that the improvement in separation and S/N you speak of is something you get with a reverse scan reader which many are installing, not because the light source is red LED. Indeed the early modern reverse scanners used infra-red LED's which would not be cyan compatible but happen to be longer lived. ("Modern" because reverse scan has been around in other forms for many years.) You will not get this improvement just by converting to a red LED light source but keeping the other components the same (there are some conversion devices that do this.)

The cyan track is acknowledged even by its proponents to be poorer sound quality and they advise compensating with Dolby SR NR, which of course one would use anyway so it's a rather moot point. It also happens to be the fastest fading dye layer on the print. The advantages of the cyan track over the traditional silver applicated track lay entirely with the labs which can skip a somewhat awkward step in processing which cannot be done carelessly without spoiling prints and they also get a bit more silver to recover from the processing chemistry.
 

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Posted by Ken Layton (Member # 133) on 02-21-2003, 08:29 AM:
 
And don't forget that you have the right to reject the cyan print as "unplayable" and tell the distributor to send a normal print. All you have to do is complain-complain-complain to the distributor if they stick you with one of those crappy cyan track prints.
 

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Posted by Scott Norwood (Member # 30) on 02-21-2003, 09:42 AM:
 
With regard to the "just use SR" comment: as I understand things, SR will improve the s/n ratio by a specific amount, regardless of the original s/n ratio. In other words, if the s/n ratio of a dye track without SR is (for example) 10dB worse than a print with a silver track, then the s/n ratio with SR would be higher, but would still be 10dB worse than an equivalent SR print with a silver track. Am I misunderstanding something here?

Also, what will happen with reprints of older titles with mono or Dolby A tracks? Will these have silver tracks, or will the labs make new soundtrack negatives with SR noise reductions? Or will they take the cheap way out and just make worse-sounding prints?

And what about theatres without SR playback capability? There are still plenty of mono and Dolby-A houses out there.
 

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Posted by Gordon McLeod (Member # 33) on 02-21-2003, 12:07 PM:
 
Ken that reject a print as unplayable probably will not work as they will be advising ahead of time of the change and this has been on the books for several years.
 

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Posted by Dave Macaulay (Member # 813) on 02-21-2003, 03:21 PM:
 
Once the labs "change over" to cyan tracks, silver or high-magenta tracks would be a special order, and probably silver track equipment will be retired and scrapped some day and that won't be an option. The silver track system requires recoating, exposing, and developing the sound track area after the picture area is done. I'm not sure whether high-magenta requires these extra steps - or why it's being phased out in favour of cyan. I think HM gives passable sound quality using red or white light, and cyan is better with red light although quite bad with white light... but once it's exposed it is developed along with the picture so no redevelopment is needed.
The sound negative does not have to change, only the processing and final appearance of the release print. On a big re-release a new sound negative would likely be produced as some audio processing changes are helpful to accomodate the cyan track reproduction characteristics. On a small volume re-release for rep houses or whatever, I doubt if the cost of the new neg would be justifiable.
 

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Posted by Gordon McLeod (Member # 33) on 02-21-2003, 09:31 PM:
 
High Magenta requires reprosessing
Alro the Sound track negative for Cyan requires different density to control the cross mod distortion
 

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Posted by Dave Macaulay (Member # 813) on 02-22-2003, 07:22 AM:
 
Thanks Gord.
Is the cross-mod problem so bad that if someone wanted a few new prints (the "singalong" Sound of Music thing comes to mind) that a new sound negative would be required?
 

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Posted by John Pytlak (Member # 331) on 02-22-2003, 09:26 AM:
 
Some links:

http://www.dyetracks.org

http://www.kodak.com/US/en/motion/support/sstLabGuide.shtml

http://www.agfa.com/motionpictures/pdf/dyetrac_jpeghigh.pdf
 

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Posted by Christopher Seo (Member # 7) on 02-22-2003, 10:34 AM:
 
Scott,

That is my understanding of SR as well: both SR and A-type have fixed noise-reducing characteristics. I believe the specs on A-type are 10 dB of noise reduction, increasing to 15 dB at high frequencies. SR provides 16 dB of noise reduction increasing to 24 dB at high frequencies. Presumably, then, it is possible to create a recording medium or transmission channel with such poor s/n that even SR cannot totally eliminate (audible) noise. Of course SR would still attenuate the noise by the 16-24 dB figure.
 

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Posted by Gordon McLeod (Member # 33) on 02-22-2003, 11:24 AM:
 
A new sound neg would be advisable
 

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Posted by Steve Guttag (Member # 268) on 02-23-2003, 05:01 PM:
 
Cyan tracks have got to be one of the stupidest things to come down the pike in years. It is a downgrade in every respect.

The proponents of it are manufacturers that have $$$ to gain. For instance, Dolby just so happens to be the chief suppliers of red LEDs for OEM manufacturers.

Kodak is supporting it in the name of reduction of print waste due to redeveloper splash (thereby keeping a film based industry alive a little longer by keeping film related processing costs down).

Labs want it to avoid the cost of redevelopment of the soundtrack. However, the labs, the ones that will gain the most, are offering nothing to the people that are paying for the red reader conversion. So all this alledged cost savings will stay with them.

The studios claim they will not convert to cyan until at least 85% of the industry is red-reader compatible (and we are not even close to that yet). Dolby uses inflated numbers on their red reader infultration claims by including ALL LEDs SOLD...thus any new or replacement LEDs whether they are for analog or digital readers (including in Dolby's Cat. 701 or 702 series readers) are added into the alledged red-reader acceptance figures.

I have found that digital replacement LEDs are about 10:1...that is, 10 replacement LEDs to every new installation sold.

Next time someone from Dolby tells you about the industry conversion...ask them if they are willing to wager, in writing on it. ShoWest is coming up...do it there where gambling is legal.

Steve
 

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Posted by John Pytlak (Member # 331) on 02-23-2003, 05:20 PM:
 

quote:

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Kodak is supporting it in the name of reduction of print waste due to redeveloper splash (thereby keeping a film based industry alive a little longer by keeping film related processing costs down).

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If you go to the http://www.dyetracks.org site, you will see that Kodak is one of MANY companies supporting the conversion to the cyan dye tracks. Eliminating soundtrack redevelopment not only reduces waste, it eliminates the use of a caustic developer containing hydroquinone, and the large volumes of water required to wash that viscous developer off billions of feet of film annually. Almost all of the silver left in a color print is in the analog soundtrack, requiring extra steps to recover in an environmental way.

Good decisions are based on weighing many factors, both positive and negative. Don't fixate on the few negative ones, when the positive ones are so great.
 

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Posted by Michael Rourke (Member # 1142) on 02-23-2003, 06:00 PM:
 
With red light readers would magenta dye getting on the soundtrack or on the optics mean that you no longer have sound?

Do labs still use film "mutilators" to rescue the silver from soundtracks or is that no longer done?
 

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Posted by Frank Angel (Member # 248) on 02-23-2003, 09:55 PM:
 
But Steve, if the conversion is driven by economic gain for the vested interest groups as you claim -- the labs and the hardware manufacturers -- rather than being driven by a demonstrable technical improvement in sound quality as the advocates have been claiming, why would NATO be on board with this? Seems like NATO theatre members are footing a rather large bill for the conversion, yet they benefit the least, economically. Obviously they must see some advantage.

I thought the downgrade in S/N was only a slight degradation. Is it really the 10db that Scott says?

Frank
 

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Posted by Steve Kraus (Member # 476) on 02-23-2003, 10:05 PM:
 
There is no logical reason for NATO to support this unless they are just sympathetic to the labs' problems. Sure we don't want prints with developer splash but that's not a huge problem for us--if some slip by they get replaced. That makes it a lab problem. So I do not know why NATO is supporting it. Usually business groups follow their members' financial interests.
 

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Posted by Gordon McLeod (Member # 33) on 02-23-2003, 10:18 PM:
 
I guess the best solution would be a conversion for despite steves comment of higher distortion reverse scan, laser and jax light all exhibit higer high freq. response and better channel seperation. As well there will be less stock wasteage and fewer rejected prints
And as for the comment a theatre cannot afford a red light conversion then they should not be in business for ever supplier will if the theatre has maintained good credit will provide reasonable credit terms and frankly 900.00 as the most expensive route is not unreasonable to stay in business.
If not then then they have been probably jerking there suppliers around any way sorry but that is a very hard reality to take and really needs to be brought into consideration
I have a very hard line to take if tomorrow the labs converted stating cyan only the only theatres I would be working through the night to convert would be those that had been supporting my business by being paid up on an ongoinging basis and the rest could go and try to find someone else and if they couldn't too bad
 

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Posted by Scott Norwood (Member # 30) on 02-24-2003, 05:10 AM:
 
Frank--I should point out that the 10dB number was a completely arbitrary number that I made up for the sake of a question/example. I don't remember offhand how much worse the s/n ratio is for dye tracks vs. silver tracks.
 

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Posted by Bill Langfield (Member # 818) on 02-24-2003, 10:41 AM:
 
On the subject of these reverse scan LED’s, how long should they last? I thought LEDS had a life of
Well, erm forever, but these things seem to only last a few years.

To keep the dolby level correct, VR1 in the LED’s power supply (Kelmar) has to be turned up all
the time to the point where, in the morning when you come in, and power up the PS just goes tick-tick-tick
and the led is pulsing, only solution is to back the power off then get a new a LED later on.
(I will have to check why the VR1 is being turned up, but I’m sure it’s because there is not enough
light coming out of the LED to wind the pre amps level up to dolby level 50%)

Also with these cyan or silver-less prints, will sound levels be effected when you run one session WITH a cyan print, then the next session with a silver print?

BILL.
 

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Posted by Jeffry L. Johnson (Member # 453) on 02-24-2003, 11:02 AM:
 
here
See Figure 6

Red Readers, Silver, High-Magenta, and Cyan Analog Soundtracks:
Review and Status

by Paul R. Goldberg

Noise Performance

Tests have demonstrated that readers based on broad band tungsten, or white light, illumination sources are quieter than readers based on narrow band red LED illumination sources (660 ± 20 nm light energy spectrum). It is believed that this is due to the fact that when the track is illuminated by broad spectrum white light, the incoherent noise sources from each of the film's color layers add on a random basis and thus the noise "averages out." If a narrow spectral band illumination system is employed, this averaging cannot take place and thus the signal-to-noise ratio is impaired. This is true whether a standard silver track, high-magenta applicated track, or cyan dye track is being presented. It is also independent of the type of release stock employed.

Figure 6 depicts this phenomenon for a standard silver track on Agfa release stock. Note that in all cases the curves for the red reader "look worse than they actually sound." This is because it is extremely rare for the bias line to fully open during actual movie sound track presentation.

Extensive listening tests at Dolby Laboratories have shown that the use of Dolby SR encoded soundtracks, although not completely eliminating the additional red reader noise, reduces its effect to the point that air conditioner noise will significantly mask the problem.
 

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Posted by Steve Guttag (Member # 268) on 02-24-2003, 11:16 AM:
 
NATO? You've got to be kidding...they haven't a clue about projection. These are the same people that brought you the polyester and ELR debacles. I wouldn't use them as a source of good ideas for projection.

In the big picture John, the film industry is best served by staying with conventional redeveloped soundtracks (not even high-magenta) and going to an IR light source. They are the most stable and best performing. Whereas the exhibitors have nothing to gain (not even cost savings for reduced print waste) they only have money to loose (purchase of a red reader system and continious LED fade) they are a poor business choice for both short term and long term money.

As to the cost of the reader, Gordon...it isn't $500-$900 it is that much PER SCREEN/Projector which can be many thousands for no benefit. Then add in the cost of repacement LEDs that, for the most part, require the services of a technican to perform properly.

Steve
 

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Posted by Steve Kraus (Member # 476) on 02-24-2003, 08:02 PM:
 
Oh but Steve, you worry too much. Installing noisier air conditioning will solve the problem, didn't you know?
 

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Posted by Daryl C. W. O'Shea (Member # 1303) on 02-24-2003, 08:12 PM:
 
Too bad for New York, cell phone related noise won't mask the cyan track noise.

Anyways, I agree with Steve, $2000 per screen for changeover houses may be affordable, but just like Fox now charging $50 to have a print delivered to the bus depot, it too is affordable, but I'm still going to complain about it.

I guess, like John pointed out, it really comes down to social responsibility.
 

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Posted by Steve Guttag (Member # 268) on 02-24-2003, 09:55 PM:
 
The social responsibility is to provide the best product you can...to better the quality of life....not fall into dubious environmental propoganda (I believe the conservatives call them, mostly correctly, enviro-wackos). Even the EPA isn't targeting the re-development process as used in the film industry.

Steve
 

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Posted by Gordon McLeod (Member # 33) on 02-24-2003, 10:25 PM:
 
Actually they are targeting in Europe and other countries so the US really ahs very little choice in it
And I can convert for around 900.00 per screen in quantity plus labour
 

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Posted by Steve Guttag (Member # 268) on 02-24-2003, 11:04 PM:
 
The US does not have to follow suit just based on what other countries are doing.

Steve
 

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Posted by John Pytlak (Member # 331) on 02-25-2003, 09:48 AM:
 
Steve wrote:

quote:

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...dubious environmental propoganda (I believe the conservatives call them, mostly correctly, enviro-wackos). Even the EPA isn't targeting the re-development process as used in the film industry... The US does not have to follow suit just based on what other countries are doing.

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Movies are a worldwide business. Many features released in the US are printed and processed in Canada or Europe. As Daryl said, social and environmental responsibility DO matter, despite the prevailing sentiments in Washington.

Since there is already a majority of red LED readers in place, the interim "high magenta" (silver + magenta dye) tracks are more compatible with the existing mix of both white light and red light readers. "Traditional" (silver + cyan + magenta) analog tracks have different cross-modulation distortion for each type of reader, making them less compatible.
 

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Posted by Steve Guttag (Member # 268) on 02-25-2003, 12:03 PM:
 
John,

Your "majority" of red-light reader comes from rather dubious numbers if they originate from Dolby. They haven't a clue as to where they have sold their LEDs...how many are replacements and how many are for digital readers.

The switch from red to infrared would be quick, painless and long lasting if the stupid high-magenta cyan agenda were to die.

Steve
 

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Posted by John Pytlak (Member # 331) on 02-25-2003, 01:28 PM:
 
So you say red LEDs are in less than 50% of theatres? If the theatres you service have a low conversion rate, could you be part of the reason?
 

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Posted by David Stambaugh (Member # 1102) on 02-25-2003, 01:45 PM:
 

 

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Posted by John Pytlak (Member # 331) on 02-25-2003, 02:37 PM:
 
Steve and I are friends. Really. But I'm just an "environmental wacko" who sincerely believes that cyan dye analog tracks are the RIGHT thing to do.
 

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Posted by David Stambaugh (Member # 1102) on 02-25-2003, 02:44 PM:
 
I know, I just think it's funny when you guys go at it over this issue. FWIW, you both make good arguments.
 

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Posted by Jim Alexander (Member # 226) on 02-25-2003, 02:59 PM:
 
I have followed this discussion in this and many other threads and in the begining I was quite concerned. Contrary to what Gordon says that if you can't afford the $900.00 per projector, maybe shouldn't be in the business, things in a single screen enviroment are a little different. Like many rural locations, single screens are the norm where we are. And with mutiplexes moving in, our share of the market is dwindling. As such, the prospect of putting out $900.00 per projector (especially when you are running a change over system) can be quite intimidating. Its not whether or not you can afford it, but whether or not this investment, at this time, is the best choice. Since I first came across this topic almost four years ago, experts (arm chair and actual) have been saying the conversion will be in 3 to 6 months. Well it is now four years later and we are still running high magenta tracks. Myself, I convered last summer to LED and have been quite pleased with the results, but if I could have put it off for another six months I would have.

According to the Motion Picture Theatre Association of Canada, 80% of theatres in Canada are converted over to LED. That may be true across the country, but not in Newfoundland, nor with the independants in Atlantic Canada. Most are waiting until there is a firm date for conversion and when that is announced they will convert.

All I can say in all this rambling is that if the industry is going to convert, then pick a date and convert. Just stop this $&@# about starting in six months and then doing nothing. False claims like this are only frustrating independants into thinking when it comes is when I will convert. My fear is that will be too late.
 

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Posted by John Pytlak (Member # 331) on 02-25-2003, 03:14 PM:
 

quote:

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All I can say in all this rambling is that if the industry is going to convert, then pick a date and convert. Just stop this $&@# about starting in six months and then doing nothing.

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quote:

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Myself, I convered last summer to LED and have been quite pleased with the results

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quote:

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According to the Motion Picture Theatre Association of Canada, 80% of theatres in Canada are converted over to LED.

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Not from what I've seen. It's probably more like 80% of screens, not theatres.
 

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Posted by Steve Guttag (Member # 268) on 02-25-2003, 05:16 PM:
 
If only that were the reason! I'd gladly thwart the adoption of visible red readers (I think that is pretty obvious to everyone) however...you'll be happy to know that our customers are probably some of the most ready...I'd estimate our customers are about 85-95% converted (I haven't done an actual count myself but there are not too many exciter lamp theatres left in our service). There are some infrareds but due to the nature of when they were available...they are a small percentage. Now we do have some screens converting from visible to infrared due to poor quality reproduction of some tracks.

Of all of our visible red reader installations, all were sold based on the reverse-scan reader quality and/or due to a Dolby Digital upgrade...none are based solely on cyan track insanity.

Steve
 

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Posted by Gordon McLeod (Member # 33) on 02-25-2003, 05:36 PM:
 
In Canada Famous Players is almost 100% red reader
Cineplex Odeon is all new installations are almost all red readers
Galaxy is almost all red readers
Magic Lantern Theatre 100% red readers
Rainbow Cinemas 100% red readers
Of the independents I service well over halh are red readers and with about another 10% IR reader
As for it being a major expense true but at no time did anyone promise that one would not have to upgrade there equipment. This same argument was used against CinemaScope and the cost of lens
Of the theatres I service that are no LED they are almost all still running obselete machinery that really deserved burial (at sea or in the landfill) years ago
The overall sonic improvement of reverse scan is well worth the investment.
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-25-2003, 07:44 PM:
 
Actually we had a theatre in Rock Springs, WY receive a Cyan Dye track print a couple of weeks ago. Apparently they were not prepared with red scanners as they called in a no/weak sound complaint. I persume they moved the print to a screen that was equipped with a red reader. This operator has since made plans to completely update his entire compliment of scanners at that location. Looks more to me like it is going to happen, and probably alot sooner than one might want it to, or expect it to.
Mark @ CLACO
 

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Posted by Steve Guttag (Member # 268) on 02-25-2003, 09:58 PM:
 
So when the July 2003 date comes and goes without a 100% cyan release...what will NATO do then? By the NATO time-table, 100% ELR reels are already a reality.

Since ShoWest is in Vegas...I wonder if they are giving odds on the cyan thing? Smart money wouldn't touch Cyan.

Steve

PS...anyone that thinks I have a dislike or disrespect for Mr. Pytlak is very wrong. We definately have differing opinons on some subjects though...cyan vs. quality happens to be one of them
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 05:57 AM:
 
Steve wrote:

quote:

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PS...anyone that thinks I have a dislike or disrespect for Mr. Pytlak is very wrong. We definately have differing opinons on some subjects though...cyan vs. quality happens to be one of them

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quote:

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Of all of our visible red reader installations, all were sold based on the reverse-scan reader QUALITY and/or due to a Dolby Digital upgrade...

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I hope that someday Steve will "see the light" --- since you can't do that with infrared LEDs.

.
 

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Posted by Steve Guttag (Member # 268) on 02-26-2003, 08:42 AM:
 
Actually,

White light is MUCH better than red light for Dolby Digital decoding.

The move to red-light readers for Dolby Digital was beyond stupid...no advantages, all disadvantages. The EPT lamps are cheaper, user changable and track better.

Steve
 

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Posted by John Hawkinson (Member # 1135) on 02-26-2003, 09:15 AM:
 
Still waiting for someone to fit a tungsten reverse-scan reader to also support red LED, ideally controlled via an automation pulse, but at the very least turning a knob or something (actually removing the bulb or LED is too much work, IMHO).

Isn't this feasable? I realize there may not be much market for it, but sounds like the sort of retrofit Steve might offer for us? [us=="the Industry"].

--jhawk
 

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Posted by Steve Kraus (Member # 476) on 02-26-2003, 09:37 AM:
 
While I realize that an incandescent bulb puts out more IR than anything else (except for the raw heat conducted & convected away!) I'm still a bit puzzled that one cannot get enough red visible light out of one to get a decent signal off a cyan track.

I also note that there now exist white LED's, UV LED's...they seem to cover the spectrum. So one presumes it would be possible to have an LED that emits across the IR and visible red spectrum. Such a device would seem to be the optimum light source, able to read cyan tracks as well as silver redeveloped tracks with the extra S/N they offer. That would probably result in different playback levels but if so since this would be part of a reverse scan unit it would probably not be too difficult to devise a way to detect which is which and build gain switching into the pre-preamp.
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 10:02 AM:
 
Steve Kraus wrote:

quote:

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I also note that there now exist white LED's, UV LED's...they seem to cover the spectrum. So one presumes it would be possible to have an LED that emits across the IR and visible red spectrum. Such a device would seem to be the optimum light source, able to read cyan tracks as well as silver redeveloped tracks with the extra S/N they offer.

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Actually, a broad spectrum ("white") LED would not be optimum for a cyan dye track. The sharpest and most grain-free layers in color print film are the cyan and magenta. Even in "traditional" analog soundtracks, the yellow layer was NOT used because it has larger grains and is at the bottom of the emulsion pack.

Here is the spectral dye density curve of Kodak VISION Color Print Film 2383:

Spectral Dye Densities 2383

A pure color LED that has most of its light output at the peak of either cyan or magenta dye will give the best signal from a dye track. A reader with a broad spectrum LED will "see" the unmodulated light coming through between the cyan and magenta dye peaks, reducing signal-to-noise. And since there is little infrared dye density, any IR energy will not be modulated by the dyes, reducing signal-to-noise. Because high-output 660nm red LEDs have established themselves in modern reader design, the cyan dye is the best choice for a dye-only track.

Component Engineering has a very complete technical discussion:

Component Engineering: Why Dye Tracks

It's very difficult to filter a tungsten light source to a pure "red" color (around 660nm). Dye filters will quickly fade, and dichroic filters would be expensive. Even with a red dichroic filter, most of the tungsten lamp's energy would be unused, adding to the heat issues and giving poor light output.
 

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Posted by Richard Fowler (Member # 893) on 02-26-2003, 11:12 AM:
 
Kinoton has a halogen / dichoric retrofit for some of their projectors....a small dichoric filter is not that costly.
Richard Fowler
Kinoton America Inc.
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 11:19 AM:
 
Do you have specifications for the spectral output of the Kinoton readers that use the red dichroics? Hopefully a peak output near 660nm and a relatively narrow bandwidth with no IR-bleedthrough.
 

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Posted by Steve Kraus (Member # 476) on 02-26-2003, 07:36 PM:
 
John, I meant only that existence of recent developments like white and UV LED's suggests that a visible red + IR LED is possible. That's what I was suggesting might be optimum, not a white LED.
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 09:27 PM:
 
If the track is dye only (no silver), you do NOT want any infrared energy, since film image dyes are relatively transparent to infrared. A 660nm red LED is optimum for a cyan dye track. A 550nm green LED would be optimum for a magenta dye track.
 

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Posted by Steve Kraus (Member # 476) on 02-26-2003, 09:30 PM:
 
Yes but not all of us are convinced that silver is going away as fast as some may suggest it is.

Besides, why is it so bad to have energy in a wavelength that is not be modulated? If the pickup device is still a solar cell it's just going to create a DC offset which presumably is eliminated at the pre-preamp stage, no?
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 09:39 PM:
 
Having unmodulated energy hitting the cell can use up its dynamic range.
 

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Posted by Scott Norwood (Member # 30) on 02-26-2003, 09:45 PM:
 
So if I understand John's comments correctly, it would be possible to play a cyan dye track in a conventional soundhead by inserting a red gel (of the appropriate color) between the exciter and the solar cell, but that sound reproduction would be sub-optimal and the gel would need to be replaced as it fades.

Is this correct? Does anyone see a market for red gel kits for theatres which haven't done the conversion by the time when (if) dye tracks become widely used?
 

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Posted by John Pytlak (Member # 331) on 02-26-2003, 10:11 PM:
 
Most red gel filters (e.g., Wratten 25 or Wratten 29) still transmit infrared energy. You would need to use an IR blocking filter as well. Red LEDs put all their energy in a very narrow bandwidth, which matches the peak of the cyan dye's spectral density.
 

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Posted by Scott Norwood (Member # 30) on 02-27-2003, 06:16 AM:
 
So the combination of a red gel and IR filter would work, then? If so, that sounds like a cheap and effective temporary solution for theatres that might receive dye-track prints. Even if the gel had to be replaced every few days, the cost would be far less than the reader conversion.

Is there any way of getting a short loop of a dye-track print to do some testing? Of the places where I have worked, only the newer (post mid-'90s) installations have LED readers; the rest are using exciters and haven't converted. Most are independents which are operating on shoestring budgets and won't be converting until it is necessary. It would be helpful for them to have a workable temporary solution if they happen to receive a dye-track print someday.
 

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Posted by John Pytlak (Member # 331) on 02-27-2003, 08:28 AM:
 
Yes, a red gel filter and an IR-blocking filter could work, but the available red light level would likely be very low, so you may not be able to get sufficient level, and the noise will be high. Unlikely to be a good solution.

Cyan dye track demos were made in the UK, titled "Red Alert":

UK Dye Tracks Meeting 2001

UK Dye Tracks Meeting 2002
 

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Posted by Jim Alexander (Member # 226) on 05-08-2003, 09:57 PM:
 
Thought I'd bring this topic back to the front again. Word has come down the line, here in Atlantic Canda, that the role out of Cyan tracks will be this fall. When? I'm not sure. Has anyone else heard anything or is this just another attempt to send a panic through the industry and make more sales for LED readers?

There are still a number of independants in Newfoundland, Nova Scotia and New Brunswick that haven't upgraded yet and are wait word as to when they will need to.

Seems to me, that almost like clock work, about every six months someone starts saying cyan is coming in "shortly" only to find out that no, they've decided to wait until more are converted. Is there a date or isn't there?
 

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Posted by John Pytlak (Member # 331) on 05-08-2003, 10:07 PM:
 
At the Dye Track Committee Meeting held at ShoWest, distributors attending were pleased with the coversion rate to red LED readers in the developed countries, but expressed concern that many areas of the world that still used tungsten light readers would not be able to play "rejuvenated" prints unless they had silver+dye tracks. Making special dual inventory silver+dye track prints for these areas would be unacceptable. The committee recognized the need to promote the advantages of reverse-scan LED readers to improve the conversion rate.

BTW, Canada has one of the highest rates of conversion to red LED readers in the world.
 

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Posted by Steve Guttag (Member # 268) on 05-08-2003, 10:15 PM:
 
In short...yet another scare.

Steve
 

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Posted by Jack Ondracek (Member # 1466) on 05-09-2003, 12:23 AM:
 
Right, but we're still at the same question. They were going to start rolling these things out in earnest this Summer, weren't they? Is that still on or not?
 

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Posted by John Pytlak (Member # 331) on 05-09-2003, 05:48 AM:
 
The July 3, 2003 date was set by NATO for conversion of their member theatres to red LED readers. It's for the distributors to decide when they want to convert the prints to cyan dye tracks only. Dual-inventory is generally unacceptable to them, so they want to be sure the vast majority of theatres are equipped to play cyan dye prints.

quote:

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In short...yet another scare.

Steve

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Steve -- you were at the meeting too. I summarized the meeting accurately, and am not using "scare" tactics, as you imply.
 

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Posted by Todd Pettigrew (Member # 1623) on 05-09-2003, 08:00 AM:
 
I have been hearing about the Cyan change for years also. Reverse scan is a whole lot easier to keep aligned focused, a whole lot easier than the old vacuum tube photocells or photocell systems. As for the change, It took between 10 and 15 years to change over to 1.85 from the academy ratio 1.37, with many of the prints in the 50's not being hard matted. I think the studios will have to wait till everyone installs modern vitaphone, DTS, or Dolby Digital before the real change comes.

My bet is on Dolby Digital becoming the standard.

I reciently talked with an editor for columbia motion pictures who was surprised that anyone still had a change over booth. The editors were talking about removing cue marks from prints. How in the world will we wever truly find the end of reels any more, provided the 24 guys before us were not too lazy to peel the tape splice in lieu of the sacraficial refrence frame.

Keep the picture sharp!
 

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Posted by Frank Angel (Member # 248) on 05-09-2003, 09:15 AM:
 
> I reciently talked with an editor for columbia motion pictures who was surprised that anyone still had a change over booth. <

Check out the thread "Last night of the Change-over" on this forum. Just goes to show you that just because some hotshot works for Columbia Pictures or is a film editor doesn't mean he/she knows ship from shinola about the nitty-gritty out in the trenches. If you read the thread, it is obvious that there are a lot more change-over booths than he had a clue about -- many of them right in the big studio screening rooms. He doesn't even have to go to the trenches.....does he think the studio projectionist at the Columbia/TriStar screening room mounts a print on a platter for a one time, in-house screening for a few company execs?

Frank
 

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Posted by Mark Gulbrandsen (Member # 72) on 05-09-2003, 07:05 PM:
 
"I reciently talked with an editor for columbia motion pictures who was surprised that anyone still had a change over booth."
_________________________________________________________________
That statemnent really confirms how far removed from the exhibition world the studios really are...
Mark
 

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Posted by Brad Miller (Member # 2) on 05-09-2003, 07:12 PM:
 
Awwww, come on guys. That statement could have been in reference to "commercial theaters", not screening rooms and special venue applications. (Let's fact it, without Guttag's installations, 99% of all normal commercial theaters would be platters or extended reels of some sort.) I have a feeling that statement from the editor was taken out of context.

As for the cyan prints, I've given up on it, as I'm tired of hearing about the threat that at this point I don't think will happen. When the first batch of prints start showing up, then I'll worry about it. A properly calibrated digital system doesn't drop out anyway, so that gives plenty of buffer to play catch-up if the cyan thing ever really happens.
 

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Posted by Phil Hill (Member # 371) on 05-09-2003, 08:03 PM:
 
Brad, you forgot my installations...it could ALSO mean special venue film loop cabinets and auto rewind systems thru the projector.

That would make it about 92%.

>>> Phil
 

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Posted by Mark Gulbrandsen (Member # 72) on 05-09-2003, 08:15 PM:
 
Brad, I think you'll find more C/O systems that you might expect out there. There are still quite a few in SLC. Most run off platters normally but the secons machine is available if c/o operation is needed.
Mark
 

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Posted by Steve Guttag (Member # 268) on 05-09-2003, 09:18 PM:
 
John,

You misinterpreted my statement...I was referring to the various scare tactics (aka ads about the coming of cyan by such and such a date or year), not your description (an accurate one) of the dye-track meeting.

Steve
 

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Posted by Steve Guttag (Member # 268) on 05-09-2003, 09:38 PM:
 
John,

You misinterpreted my statement...I was referring to the various scare tactics (aka ads about the coming of cyan by such and such a date or year), not your description (an accurate one) of the dye-track meeting.

Steve
 

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Posted by Brad Miller (Member # 2) on 05-09-2003, 11:14 PM:
 
Hmmmm, looks like someone is using and IE browser!
 

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Posted by Steve Kraus (Member # 476) on 05-09-2003, 11:54 PM:
 
The committee recognized the need to promote the advantages
of reverse-scan LED readers to improve the conversion rate.

But such promotion is deceptive if it infers that these benefits stem from conversion to red light when in fact it's because of the reverse scan technique and that the absolute best analog playback comes from a modern reverse scan reader equipped with an IR LED playing a traditional (not high magenta) applicated track. Surely the entire truth should be told and let the chips fall where they may.
 

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Posted by Gordon McLeod (Member # 33) on 05-10-2003, 08:10 AM:
 
No I think the pull up on steves changeover browser was wrong and the missing ID frames caused it to repeat twice
 

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Posted by Ray Derrick (Member # 1001) on 05-11-2003, 06:20 AM:
 
I sat in on the ShoWest cyan dyetracks committee meeting also and was somewhat bemused by Ioan Allen's comment (and I hope I am quoting him accurately) "maybe we need to force them (the remaining theatres) to convert" (by releasing cyan prints now and causing havoc, particularly in those markets that are given rejuvinated prints). If Ioan was speaking on behalf of Dolby you can draw your own conclusions about that company's attitude to cinema exhibition in poorer countries. Sorry Ioan, but you said it.

Also with all due respect to John P, who reported that distributors "expressed concern" regarding the distribution of cyan rejuvinated prints, my reading of what was said is more along the lines that several distributors predicted dire consequences for those markets using rejuvinated prints. I guess the interpretation of what was said is somewhat coloured by one's own views on the subject, true John?

Personally I am in full agreement with Steve on this issue, despite the fact that my own company makes some good money out of Red LED readers. Plastic bags cause infinitely more damage to the environment than the comparatively tiny amount of chemicals used in redeveloping soundtracks, but do I hear the cyan proponents screaming from the rooftops about phasing out plastic bags? The whole thing is about a select few companies making some big bucks at the expense of good quality analog cinema sound and anyone who says otherwise is either fooling themselves or is in the queue for some of the big bucks.
 

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Posted by Ken Layton (Member # 133) on 05-11-2003, 11:13 AM:
 
Ray:

I couldn't have said it better myself. I should print that out, laminate it and hang it on the wall! You're spot on.
 

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Posted by Frank Angel (Member # 248) on 05-11-2003, 11:14 AM:
 
Now if only someone would make a reader that you could easily switch from red LEDs to IR LEDs for the venues that program both retrospective and current titles. Will the solar cell in the red readers work with IR exciters or are they not sensitive to in the infrared range? My concern is for all the rep houses out there like ours that mix retrospective with current titles, and want to keep the reverse reader with white or infrared exciters for conventional prints, but are then in a pickle when the cyan tracks come along.

Kelmar still stocks infrared exciters. I was toying with the idea of purchasing a pair and using them with the red readers. In other words, could I switch just the exciter when I need to play a cyan track but use the IR exciter for conventional prints? I imagine this would require an entire A chain alignment, right? An exciter array that contains both red and IR and is switchable would eliminate alignment and it would be a great boon for the alternative venues.

Frank
 

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Posted by Steve Guttag (Member # 268) on 05-11-2003, 11:44 AM:
 
Frank,

I don't think you have read my previous rants....

All of the solar cells used for optical sound reproduction, be they forward scan or reverse...ARE IR SENSITIVE...infact, the "red readers" are using an IR sensitive cell and hence one of the many reasons red readers are inferior. No matter how many times the cyan-morons dance around it, they canna break da laws o physics captn.

As long as they use the cells they are using, Infrared IS THE light source, period...all others bring with them problems...the exciter lamp (tungsten bulb) works because of its IR engergy, not the other colors.

The Component engineering LEDs are socketed but I wouldn't call them user changeable. The BACP LEDs are easily changed on their head mount...the head is socketed so rewiring is eliminated presuming the head can be wired for the different polarity...yes, I've found that IR leds are opposite to RED.

Some of our rep houses are now IR LEDs and some more are switching (but keeping the visible RED LEDs at the ready if the ugly cyan crap does happen.

Here is another IR benefit...those LEDS last MUCH longer than the visible LEDs and they are MUCH more stable...come back years later...Dolby Tone still on the money.

Steve
 

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Posted by Jean-Michel Grin (Member # 1360) on 05-13-2003, 04:31 PM:
 
The solution if your boss dosen't want to invest some money to upgrade all analog readers to Dye track. Play all features in Bypass
You will see that all customers will notify the bad sound to the management....
You don't need to be Jackass' addicted on MTV to make that, but OMHO Is better to try to speak with the manager to explain how munch it's important to convert a theater for the cyan soundtrack
 

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Posted by Steve Kraus (Member # 476) on 05-13-2003, 06:01 PM:
 
Steve, will IR LED's also work with the DD CCD array?
 

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Posted by Steve Guttag (Member # 268) on 05-13-2003, 08:50 PM:
 
The change to cyan can hardly be called an "upgrade"...in fact, it is properly called a DOWNGRADE...it is inferior to redeveloped tracks. The only benefit is to the labs and to the red reader manufacturers (the biggest one being Dolby).

I'd encourage the exhibitors to call their lawyers and sue a distributor for forcing a cyan track on them...or they could provide the red readers with the print (and a check for its installation).

Steve
 

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Posted by Paul Trimboli (Member # 1509) on 05-14-2003, 07:46 AM:
 
I have noticed that on soundtrack with High Magenta they really make the gate dirty, the rag we use to clean the gate is full of that colour, would Cyan do the same? Does normal B/W do this but you just can't see it on the metal?
 

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Posted by John Pytlak (Member # 331) on 05-14-2003, 08:33 AM:
 

quote:

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I have noticed that on soundtrack with High Magenta they really make the gate dirty, the rag we use to clean the gate is full of that colour, would Cyan do the same? Does normal B/W do this but you just can't see it on the metal?

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