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filmguard is preventitive

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I think that's the important point. PTRs may work well in film labs, but theatres are a different situation. Most of the dust found on a print is generated in the projector itself. PTRs will remove the dust but won't prevent more dust from being generated, and won't prevent abrasive deposits from building up in the gate, as Film-Guard does.

Also, as Randy pointed out, PTRs can quickly become overloaded. Media cleaners are the fastest way for a theatre to clean a dirty print.

The only exception is Imax theatres, whose rolling loop mechanisms are incompatible with Film-Guard; they do use PTRs to good effect. (However, I'm now wondering why they don't use media cleaners dry, at all.)
 

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Posted by Dan Lyons (Member # 1454) on 04-12-2004, 02:29 AM:
 
Did I hear someone calling my name??

Robert,

Look to your left and click on the "reviews" button. You'll find out all you want to know about PTRs. Also, do a few searches for PTRs; you'll end up with all your questions answered.

Who on earth told you to switch to PTRs??

danny
 

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Posted by Darren Briggs (Member # 1071) on 04-12-2004, 08:19 AM:
 
I currently use PTR rollers and feel if you use them every show, they work very well indeed.
If you only run them once a day or some site once a week, they do get loaded up with all the dirt and become in effective.

I use film guard to clean old logos, and on prints that shed alot of dust, I coat the edges of the film with film guard when making the print up. This also way is ok to use with PTR rollers once the film has been run twice. The PTR's are still perfect.

Darren
 

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Posted by Mark J. Marshall (Member # 1409) on 04-12-2004, 10:21 AM:
 
I've always found that particle transfer rollers are great at exactly what their name implies... transferring particles from one part of the film to another.

Sounds to me like someone is trying to save a few bucks.
 

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Posted by Scott Norwood (Member # 30) on 04-12-2004, 10:32 AM:
 
PTRs work fine _if_ you start with a new or very clean print and use them for every show. They need to be cleaned and replaced for every show, too. Under those conditions, PTRs are useful for keeping new prints looking new. They are useless for old, ratty prints.

FG and media cleaners do this, too, but are also effective at cleaning up lousy prints and hiding scratches. Given the choice and operators who can be trained to deal with the media cleaners, I'd take FG+media cleaner over PTRs.
 

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Posted by Mike Blakesley (Member # 26) on 04-12-2004, 12:45 PM:
 
Another point: It actually takes MORE time to clean the PTR rollers than it does to rewind the media pads between shows. How many PTR users are faithful about cleaning the rollers between EVERY show?

FG might cost a bit more to use but it probably balances out with the time saved (not only on the cleaning of PTRs, but on cleaning projectors) and on-screen quality improvement. I am still amazed at the amount of gunk that comes off even a slightly used print when we FG it.
 

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Posted by John Pytlak (Member # 331) on 04-12-2004, 01:00 PM:
 
Kodak introduced PTR film cleaning technology in 1989. I presented two SMPTE papers.

PTRs are effective film cleaners and do not redeposit dirt, as long as they are not overloaded with so much dirt that the tacky surface is covered. As Scott notes, a really filthy print will overload the PTR. In our tests, it required several passes to clean a really dirty print. Although washing with water and detergent is the best way to remove any buildup, many have found that a "see-saw" with a piece of low stick artist's tape will quickly remove any accumulation of debris from the PTR.

PTR's are especially useful when you do not want to put anything on the film. So they are widely used for cleaning raw stock, printing originals, films being transferred to video, and for films that come into direct contact with optics (e.g., IMAX prints).

PTRs are very low risk to the film, as they are very soft and have a "rolling contact" with the film. In our testing, we sprinkled sandpaper grit on PTRs and ran camera negative over the grit-laden PTRs several times without scratching, indenting, or damaging the negative. You would never dare do this with a dry media cleaner, as the abrasive particles would scratch the film.
 

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Posted by Brad Miller (Member # 2) on 04-12-2004, 01:20 PM:
 
Any theater that has a booth environment THAT dirty doesn't stand a chance at a good presentation anyway, John.

I have never seen a PTR do what I would call a truly effective job. Others have disagreed with me...UNTIL they saw what their presentation COULD look like. This is why so many people roll their eyes at others who claim their PTR presentations are so flawless. They don't know what they are missing. I have never had a case where a projectionist who was a fan of PTRs wasn't completely amazed when he saw a media/FG presentation and promptly threw the PTRs in the trash and went the media/FG route.

PTRs are great for labs and such and they look spectacular on paper, but are pretty much useless in the field. Plus every run they have they get less and less effective. Not so with the media cleaner.
 

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Posted by John Pytlak (Member # 331) on 04-12-2004, 01:25 PM:
 
There's an old saying: "Different horses for different courses".
 

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Posted by Brad Miller (Member # 2) on 04-12-2004, 01:27 PM:
 
Say what you want John, but it was you who commented that the Titanic print you saw at Northpark which was media/FG was the best presentation you had seen. We received the print used with light scratches on it too...but I'll bet you didn't see those on the screen.

FilmGuard may not be a Kodak product, but you were damned impressed that day and you can't deny it.
 

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Posted by John Pytlak (Member # 331) on 04-12-2004, 01:34 PM:
 
There are applications where you can't use FilmGuard, such as contact printing where if it gets transferred from the printing original to the raw stock, it will affect the processing. Likewise IMAX prints that come into direct contact with the field lens. Remember, like FilmGuard, PTRs were developed to address the deficiencies and risks of film cleaning with dry media.

BTW, when I saw "Titanic" in 70mm and visited the Northpark booth in February 1998, Ron did NOT make a point of showing any use of FilmGuard. I know it was still under development at the time. Was it used for every showing, or just as needed?
 

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Posted by Brad Miller (Member # 2) on 04-12-2004, 01:51 PM:
 
Re: Northpark - other than the showing you attended, Titanic was passed through FG on every show and those scratches disappeared after a few runs. Ron took the media cleaner off of the platter and locked it up in the cabinets when he found out a Kodak guy was in the building per our agreement to keep it completely private until it's release. I just missed you too at the shift change. (Your business card remained on our corkboard until the theater closed.)
 

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Posted by Darren Briggs (Member # 1071) on 04-12-2004, 04:02 PM:
 
Brad/John,
You are both sides of the battle and I would say you both have put your points across.

Film Guard is something that im sure makes lots of money for you and well done for bringing out a product that can help make prints look new once theve been to a load of 'film done wrong' cinemas.

PTR'S a Kodak invention work well too if used correctly and in a multiplex environment may be too time consumming to use corretly, hence they get a bad rap for not cleaning prints well.

I use both products, and can assure you PTR'S work, and Film Guard works, allthough the Film Gaurd is normally only used on the bench in my sites. Day to Day shows run on PTR.
I just have never wanted the risk of a scratch putting on a print via a slow moving media cleaner, allthough FIlm Guard will probably repair the scratch!
But PTR'S have worked wonders on the used print of 'Passion of christ' that I'm running at present. Was dirty, now spotless. Just viewed it and seen the improvement.

To sum it all up, this battle will go on forever, it is down to the individual to choose where to put there money, I have both.

PTR'S are good enough for IMAX, there good enough for me.
Film Guard does amazing things to old knackered prints.

Darren
 

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Posted by Robert Edgecomb (Member # 2335) on 04-12-2004, 04:42 PM:
 
Thanks Darren and everyone. My philosophy which has come out of a few months of experimenting with both FG and PTRs is that they both work. I use PTRs on ever show and then FG only when greately needed. The prints have gotten ebtter by this technique and some have even improved. PTRs though just seem to take the dust away and it keeps coming back which is a pain. THanks everyone. I know I will have more questions in the future, especially about scratchs. I have a print of 'Touching the Void' that has short horizontal scratches (both black and green). I think it is from the sound roller. I dont know. Thanks again.
 

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Posted by Joe Redifer (Member # 3) on 04-12-2004, 04:54 PM:
 

quote:

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John Pytlak wrote:
In our tests, it took several passes to clean a really dirty print

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quote: Darren Briggs

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PTR'S are good enough for IMAX, there good enough for me.

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Oh my, you simply MUST come visit some of the IMAX theaters I've been to. Their prints were insanely dirty! Everyone who visited the Dallas IMAX at Fair Park about a year ago at our gathering can attest to the lousy presentation there. The same thing goes for the dirt tornado at the Cinemark Webb Chapel 17 in Dallas. It's like they are just throwing shovels of dirt on the prints. I suppose if that's good enough for you though, more power to ya.
 

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Posted by Robert Stawiarski (Member # 1842) on 04-12-2004, 07:50 PM:
 
Brad, you simply MUST come visit some of the IMAX theatres I have been to. We run a pretty tight ship here in Lincolnshire and try and keep our presentations looking as good as possible. I have also been to the Navy Pier IMAX and their prints are run clean. Like with anything else, you will find better results based on the people that are running the system and the pride they take in the presentation.

IMAX is quite different from 35mm in that the film is directly in contact with one of the optics. While the 'dirt' projected on screen in a 35mm presentation is only for that specific frame and disappears immediately after it is projected, in IMAX, the dirt you may see may stay there throughout the entire show if you have a sub-standard operator (especially if the 'dirt' is on the back of the field lens). It does not necessarily mean the print is 'dirty' or PTRs are ineffective. There are a variety of factors that can affect an IMAX presentation that are not directly related to PTRs. How well does the operator clean out the rotor, gates, and stators between shows? How well does the operator clean the field lens (including the back, where the wiper bars do not swipe) between shows? For example, if the back of the field lens is not cleaned properly, an otherwise clean print will look 'dirty' on screen because the wiper bars do not clean the back when cycled. Is the field lens cycle on?

Is it a relay based system where either the projection operator or console operator need to cycle the field lens manually and were not doing so? The newer PLC based systems have an auto-cycle, but it can be turned off and the dirt will accumulate throughout the show without being swiped off. Are the wiper bars changed regularly? If they are not, their cleaning effect will be reduced. Were they even installed?! Are the tolerances set correctly (abnormal print shedding can occur if they are not)?

IMO, it is a bit of a stretch to say you have been to a few poorly presented IMAX presentations and thus conclude PTRs are completely ineffective without considering the other variables; we do not all run 'dirt tornado' shows nor do plenty of other IMAX theatres.
 

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Posted by Brad Miller (Member # 2) on 04-12-2004, 08:21 PM:
 
Don't put words in my mouth Robert. I have done more than enough testing in the 35mm world to know PTRs are only slightly effective and they were all fair tests with two identical prints side by side (mostly compared to running PTRs vs. dry media). Comparing a method of cleaning between different film stocks, or different projection equipment, or especially between 35mm and a format like IMAX is just ridiculous. Where are you pulling this nonsense out of?

I am doing some traveling in the near future and part of those plans is to stop in to any IMAX theater within reasonable distance for a screening. I'll report back then what I find. That doesn't change the fact that PTRs are not all that effective and it also doesn't change the fact that the IMAX theaters around here are lousy and giving IMAX a bad name. (By the way this issue has come up before and even a year later nothing has been done by IMAX to remedy the situation at these locations.)

To answer your question, it would appear the wiper cleaned the lens at least every 5 seconds or so. I don't ever recall seeing dirt that remained in place for an entire show though.
 

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Posted by Robert Stawiarski (Member # 1842) on 04-12-2004, 09:17 PM:
 
Well, for the record, we use FilmGuard here for our 35mm prints and are pleased with the results, which is what the original poster asked in the first place. All of our 35mm prints presented in our IMAX theatre are treated with FilmGuard for a reason.

I only brought up IMAX when you referenced your bad experiences with IMAX in response to Darren's quote: "PTR'S are good enough for IMAX, there good enough for me." Obviously, I would not have brought up another film format if it was not referenced, especially in a negative light, in a previous post. It's akin if I were to say: "I saw a dirt tornado 35mm showing that was treated with FilmGuard and it looked like they were shoveling dirt on the prints," and then say it is ridiculous nonsense if you were to reply and state other factors of how it may not have been applied properly, etc.

No hard feelings. Now back on topic!
 

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Posted by Phil Hill (Member # 371) on 04-12-2004, 11:38 PM:
 
The best use I've found for PTR rollers is as a lint remover from clothes....

>>> Phil
 

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Posted by John Pytlak (Member # 331) on 04-13-2004, 12:27 PM:
 
The risk of scratching a print with dry web media isn't usually from the media, it's from the abrasive particles that get caught in the media. I once saw a print severely scratched from head-to-tail by a projectionist who tried to use a dry media cleaner to clean a print that had picked up cement dust from some demolition work of a cinderblock wall when the booth was being expanded. The used dry media looked like a strip of sandpaper.

Phil: Didn't iWERKS use mostly PTRs for on-line cleaning?:

http://www.film-tech.com/pics/tinseltown/tinseltown.html
 

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Posted by Brad Miller (Member # 2) on 04-13-2004, 01:34 PM:
 
Two posts up of mine I addressed that. The media we are sending out now is textured to permit the dirt clumps to fall into the groves of the media for cleaning even under extreme conditions such as that without scratching. (Kelmar offers a similar product, but none of the other manufacturers do.) While that is a valid concern, I've opened theaters and ran booths with MAJOR amounts of construction dirt with media/FG and never had a scratch. I am talking where if you wiped down the platter decks, that within a few hours there would be another noticeable layer of dust that you could take your finger and write "PTRs don't work in this environment" in the dust. Care to do a side by side comparison under such extreme conditions?
 

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Posted by Frank Angel (Member # 248) on 04-13-2004, 03:19 PM:
 
Long ago I found that the air conditioning system in our facility was producing lots of particulate of unknown makeup or origin. Fixing the system was a solution beyond the scope of our operation so I decided to simply block all vents that supplied dirty air and I installed air two air scrubbers in the booth as well as a large capacity air conditioner to make up for the now lack of cool air supply (which was always marginally effective to begin with). The air scrubbers which used a combination of mechanical filtering and electrostatic charged plates pulled a frightening amount of dirt out of the air in the first months. Luckily our floors are painted cement rather than carpet (which is known to hold lots of dirt), I took to using a wetvac to wash and dry the floor once a week. This combination seemed to make a substantial difference in the amount of airborne dirt that is now captured by the air scrubbers the air conditioner filter.

Seems that capturing and eliminating the dirt before it can be attracted by the film's static charge attacks the problem on the front end, yet this is rarely considered in booth construction or operation. If booths were operated as near-clean rooms, new prints would rarely need the kind of constant cleaning that standard booths seem to require.

In another theatre there is a rug and so wetvac is not an option, but I have them vacuum the floor with a vacuum cleaner that has a hepa filter. I am not as convinced of this procedure's efficacy since I don't have any way to know if the filter on the vacuum is effective enough to prevent dirt from being picked up from the rug and then have some of it spued back into the room. Rugs, as sexy they make a booth look, are not what should be installed in projection booths, IMHO.
 

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Posted by Christian Appelt (Member # 1067) on 04-13-2004, 03:36 PM:
 
PTRs are OK, as John P. pointed out, in the film lab and on telecine machines. Both places (hopefully) have much cleaner air than the average projection booth and employees there are trained to handle valuable original materials.

I have seen (in theatres) wet cleaning from Kinoton/Retheto, antistatic carbon fiber brush cleaners and PTRs that were cleaned every two shows.

None of these solutions compared to FilmGuard.
The Kinoton cleaner had stationary pads and a quite primitive liquid dispenser. This type of cleaning was effective on new prints, but the cleaning fluid seemed to be hazardous to health and if the projectionist forgot to replace pads only once, you got really bad scratches.

The PTRs did what was mentioned in this thread, they took dirt away from reel ends and solices, spreading it equally over the whole print. When they were cleaned to manufacturer's specifications, they detoriated and fell apart within two months.

Second best to FilmGuard I would rate the carbon brushes, I had a print running for 8 weeks in a booth with bad air condition equipment and a lot of dust. The print was not scratched after that run, and the image looked dirt-free. The only drawback was that any kind of grease or oil (on old print and especially foreign prints from india ) would clog the fibers and cleaning them was hell.

In other words, if there was no FG, I would recommend carbon fiber brushes, PTRs would be last on my list.
 

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Posted by John Wilson (Member # 269) on 04-13-2004, 06:52 PM:
 
OK, I'm a little late getting to this one, but you knew I'd be here sooner or later...

The cost comparison isn't much of an argument. For PTR's to have continued effectiveness, they need to be replaced from time to time or the tackiness will disappear. You'll then end up with just four rollers moving over your print for not very much reason. How often do PTR's get changed in your booths? Ever? Are you still running with the originals?

There is no way that ANYONE, that't right, ANYONE who has used both (ESPECIALLY in a side by side comparison) could say that PTR's are more effective than FG. That's just nuts. PTR's are good in the labs and to a certain extent are useful on IMAX prints but simply for no other reason that there's not much else to use as an option.

If you are cleaning tags etc. with FG, why not use PTR's? There must be a reason.

Filmguard every time.
 

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Posted by Phil Hill (Member # 371) on 04-15-2004, 06:49 PM:
 
John Pytlak said:

quote:

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Phil: Didn't iWERKS use mostly PTRs for on-line cleaning?:

http://www.film-tech.com/pics/tinseltown/tinseltown.html

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John: Iwerks did try using PTRs for awhile. We tried many different film-cleaning methods. ...Both in the lab and in the field. Commercially available systems as well as some of our own designs.

In the specific case that you link to, PTRs were proven unnecessary as that particular system had its own filtered air supply that kept the film clean. The PTRs were disabled and that cleaner was discontinued in all Iwerks applications as well as that particular projection system. Which, by the way, they were discontinued as not being practical and for not providing any noticable benefit.

In an application that projected a 3-minute simulator-ride film about 12 times an hour for 20 hours a day (=240 times each day) PTRs are a burden. They are a high-maintenance item that NO ONE would maintain!

As far as 1570 applications, yes we used PTRs. But, we had MUCH trouble with the peeling off of the emulsion due to not knowing that there were 2 versions of PTRs. A high-speed (read for 1570) version that had a matt finish was required for our applications. KODAK supplied us with the standard “high-gloss” versions that cost us many big-time bux for damaged prints.

I still really question the benefit of PTRs in ANY application. I must have 20 PTR rollers around here at home that I use for lint pick-up! (I just have a lot of leisure suits from the 70s!)

In short, I think for applications other than lint removable, PTRs are great for HIGH maintenance applications such as labs. But for the real world... forget it! They SUCK!

>>> Phil
 

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Posted by Richard Fowler (Member # 893) on 04-15-2004, 07:55 PM:
 
Most of the endless loop cabinet installs I did some time ago...the room was climate controlled and particle free, the cabinet had a positve filtered air flow and air sqeegues where installed just prior to the projection head....most prints where replaced due to print fade and where dirt free. I use PTR's to clean film negatives I handle. Our experiments with PTR's in clients cinemas would find them crudded up after running 30 - 40 minutes of film ads prior to the feature...I have sold a couple of advertising film producers media cleaners so they can Film Guard their prints for recycling and film preservation.
 

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Posted by John Pytlak (Member # 331) on 04-17-2004, 10:35 AM:
 

quote:

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Our experiments with PTR's in clients cinemas would find them crudded up after running 30 - 40 minutes of film ads prior to the feature

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Many rolling stock ads are printed on "no name" film stocks that are unfortunately still more prone to projector abrasion and "shedding".
 

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Posted by Brad Miller (Member # 2) on 04-17-2004, 10:47 AM:
 
So John, what you are saying is that any cinema that runs rolling stock shouldn't use PTRs because they clog up with dirt too easily because non-Kodak filmstocks shed too much?

If that's not what you are saying, then what are you saying?
 

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Posted by Dave Williams (Member # 299) on 04-17-2004, 11:15 AM:
 
Having been in the situation of having to speak for my companies products and also having to admit without bieng able to admit that our product is not for every circumstance...

I think that John is saying that PTR's are very good for thier true intended use, (labs, IMAX, other uses where direct contact with film or negative stock would cause problems were FilmGuard used).

However, in cases where today's non union projectionist world, where we have the lowest common denominator in hired projection in MANY cases, the use of PTR's would provide little benefit, as they would not be used properly.

FilmGuard is easy enough to use even stupid people should be able to figure it out, and it is really stupid people proof for the most part. I think john has pretty much eluded to that point, without bieng able to really say that. So it is a better tool for most than PTR's.

I think he said it when he said something like "different horses".

On the film stock issue, note he said "no-name". I used to use the same term when describing anyone other than us. they must mean Fuji?

Of course, John really can't agree or disagree anyway. Who knows what kind of slave drivers those kodak guys are?

Ciao

Dave
 

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Posted by Richard Fowler (Member # 893) on 04-17-2004, 11:41 AM:
 
The rolling stock of one company is printed by Technicolor on Kodak stock. The other company uses a major processor using Agfa print stock. Same results. My opinion the crud on the prints are based on trailer makeup and breakdown practices. "No name" would be a catchy Trademark...we are no name but we try harder
 

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Posted by Mike Blakesley (Member # 26) on 04-17-2004, 12:19 PM:
 

quote:

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Of course, John really can't agree or disagree anyway. Who knows what kind of slave drivers those kodak guys are?

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