|
|
This topic comprises 2 pages: 1 2
|
|
Author
|
Topic: filmguard and failsafes
|
Carl Martin
Phenomenal Film Handler
Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002
|
posted 01-03-2004 06:09 AM
our tech mentioned he was told that some ua's in colorado had stopped using filmguard because it was tripping their failsafes and shutting down shows. i don't know what model or anything, but supposedly the f-g interfered with the infrared sensors.
can anyone confirm/expand upon this rumor. i don't know too much about optics but my feeling is that since f-g refracts light just like film, this is unlikely.
nevertheless, it was brought up as we've been having trouble with our fm-37. in addition to this , our shows have been shutting down right at the start, around where the leader ends and the company logo starts. 2, sometimes 3 presses of the start button have been necessary to keep the show on screen (the rest of the show runs fine).
various things have been done by the techs, and there were no problems on my last shift (new bottom roller on aw3r, newer leader), but since the filmguard issue came up, i'd like to hear if anyone has any thoughts on that.
carl
| IP: Logged
|
|
|
|
|
|
Carl Martin
Phenomenal Film Handler
Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002
|
posted 01-04-2004 04:06 AM
well, the failsafe has been cleaned many times. for a couple days we were defeating the motion detector as a temporary measure, which worked, but our tech told us not to do that.
the fm-37 is the updated version. i don't know how to check the sensitivity of the leds.
our films on all 3 screens (we rotate them frequently) now have new leaders on them, and all shows have started fine since friday, when the first new-leadered film rotated into the "problem" house. of course, that was the day the platter roller was changed and possibly the fm-37 itself was tweaked some, so it's hard to say what exactly helped.
i brought out one of the old leaders, put a trailer on it, and ran that 3 times to see what would happen. it started fine. if i get a chance i'll try running all the old leaders, since i don't know which ones were being used when the shutdowns occured.
one thing i've noticed which obliquely implicates filmguard is that the leaders and company logo would get patches of "mud" on them. this is no doubt because our union guy still gets his leader on the floor when threading, and the resulting dirt collects together in mucky patches. these were present on the test leader i ran, but perhaps not on the edges where they would interfere with the sensor leds.
maybe i'll get lucky and find an old leader with edge mud that will trip the failsafe, and that will confirm it. my fear is the filmguard itself will be blamed for this, not the poor handling.
as it is, our tech wants to discontinue f-g for "a month or so". i'm trying to convince him to let us at least run it on one print so we have some basis for comparison. hopefully our union guy will mend his ways.
the tech has spoken to another tech in new mexico who says he has an fm-37 with the same problems, and f-g was used there. i want to find out how they treat their leaders there.
does this scenario sound plausible? is there anything else i can suggest to our tech? i feel like this is largely a public relations problem as far as filmguard is concerned. hell, the company isn't even ordering it for us anymore and we're running out.
carl
| IP: Logged
|
|
Brad Miller
Administrator
Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99
|
posted 01-04-2004 05:04 AM
Carl, not to "out" the stupidity of your tech, but really, the guy's missing some brain cells here. (The biggest hint was changing the platter roller. The lower magazine roller maybe, but the platter roller??? Even if the platter roller was wobbling, the lower magazine roller would've been the only roller in the entire chain to possibly have caused a seating problem with the failsafe. ![[Roll Eyes]](rolleyes.gif) )
Let's look at the scenario.
First, FilmGuard has been on the market for 5 years and has been run on undoubtedly hundreds of thousands of passes through Component Engineering failsafes. This is the first "claim" that I have ever heard of potentially causing a problem. As such, the theory is pretty fishy...especially since I personally started using FilmGuard with FM35 failsafes somewhere around 1989/1990 and not one hint of problems ever turned up. Even your theory of the sloppy union operator putting the film on the floor doesn't hold a ton of water, because I know of MANY theaters who do that and it has never been an issue other than to degrade the presentation. If the leader is to blame, I would point the finger at it being "chewed" for lack of a better term.
Second, you say this problem only happens during startup where the leader is joined to the first trailer. You do FilmGuard your ENTIRE print, right? Just making sure that you don't run FilmGuard on the end of your leaders and then pull the film out of the cleaner. Again, this shows that the "constant" (in this case, the FilmGuard) is not to blame.
Third, you have stated this is only a problem in one auditorium, whereas your other projectors are running fine. Geez, if you FilmGuard all of your prints, how does the FilmGuard magically know which auditorium to mess with?
Your tech has either laziness issues or needs to go back to troubleshooting school. It isn't the FilmGuard. Try giving Component Engineering a call, because it sounds like the sensitivity is set too high on that failsafe.
By the way, can you upload a picture of the leader stock you are using, or at least tell us who your vendor is so we can try to figure out what it is? Also (specifically more important), do you have a stretch of black at the end of your threading leader? It has been widely documented that the older FM35/37 failsafes have had issues with B&W stocks, various black leader and silver retention prints. That coupled with a slightly over-sensitive sensor would make for a solid guess at the real cause of your problem. Again, check with Component Engineering regarding the adjustment. In the meantime, do a search on the forum for "FM35" and check out the various tips that people have offered in the past. Physically flipping that troublesome failsafe with another one in the complex will also tell you a lot when you find that the problem follows the failsafe.
| IP: Logged
|
|
|
|
|
|
Jack Ondracek
Film God
Posts: 2348
From: Port Orchard, WA, USA
Registered: Oct 2002
|
posted 01-04-2004 01:03 PM
Tim's got an interesting point. I've taken one of those handheld fluorescent work lights near an FM35 & shut down a show by getting it too close. Still, I think this argument is getting spread too thinly, in order to infer blame where it can not be.
If the FM35 is shutting down the show at the same point each time, and if other prints run through that screen without difficulty, the problem HAS to be on the film. The most obvious way to trace the problem is to just look at the detector, wait for the motion light to go out, then note where on the film that happened. The motion detector is not a particularly fast-acting circuit, compared to the foil detectors. Filmguard and "Booth Floor Mud Blobs" ![[Confused]](confused.gif) would have to be pretty evenly applied to probably a foot of film to have any effect... even if this was possible. "Booth Floor Mud blobs" would go by too fast to be noticed (geez... I can't believe I'm hearing this). Seems the cleaner would get all that nasty floor gunk anyway, and to have that much crud on your floor to effect a cue detector must mean you're going through a couple of media rolls a day, eh?
Another thing... if you're noticing that much dirt on your leaders, why not clean the darned thing off so you don't have to blame contamination, and we don't all have to defend a product that works literally everywhere else in the world? If your detector is that darned picky, get a cloth and some naptha, clean off your leader & see if it works then. IF it does, you might even go so far as to (properly) apply a fresh coat of FG, just to eliminate this as an issue... either for you or for your company's lazy technician.
| IP: Logged
|
|
Randy Stankey
Film God
Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99
|
posted 01-04-2004 01:12 PM
Once you have the failsafe's "windows" cleaned and you have eliminated that problem the next thing to look at is film path alignment.
Adjusting the lower magazine/take-up rollers is a good place to start. If one roller in the path is sticky or misaligned it can cause a ripple effect back to the failsafe which will make the film jump or move out of alignment.
One time I had to track down a similar problem and I found that the "keeper" on the lower magazine roller was too close to the main roller. It only had a small amount of clearence. When a splice (especially a poorly made one) went through that roller it would get caught and "hang up" in the roller. That momentary jolt in the film was enough to trick the failsafe into shutting down the machine.
I suggest checking for those kinds of problems. While you are at it, make sure all your rollers are aligned perfectly. I have seen many occasions where operators get sloppy and bump rollers out of position. Over time those misalignments stack up and work against you.
Also, look at the rollers on the failsafe itself. They can become loose. If they aren't in the exact right position they can cause the failsafe to be cranky. Hey, if the film isn't going under the sensor the way it ought to how can the sensor do its job? While you are down there, check to see if the sensor assembly has become bent. The sensor assembly must be perfectly parallel to the black roller. If it's not the sensor can't do its job.
Furthermore, your sensor might be getting weak. They just do that sometimes, even if you have the updated design. The easiest way to tell if a sensor unit is weak is to swap it with another one that is not suspect. If the problem moves with the sensor, you know where the problem lies. Replace the weak sensor and the problem should clear up.
Finally, there are some types of film that just don't like the FM-xx failsafes. Like John said, black & white or "high silver" prints are sometimes less reliable in them. You can fight that by keeping your failsafe clean and well aligned. If your equipment is clean and properly aligned you should have no more than one or two prints a year that cause problems.
My FM-35 failsafe works perfectly almost all the time. Every once in a blue moon, it will act up on me. The first thing I do is clean it and check the film path. This will clear up 90% of my problems right there. This only takes a minute. The next thing I do is check the film at or near the point where the problem occurs. About half the time I find one of those distrubutor logos has been spliced in and it's on one of the kinds of film that doesn't like FM-xx. If that piece of film is taken out the rest of the movie runs perfectly. (Dont' forget to put that film back on when you send it back!)
Now, we're down to less than 5% of the problem films. What I do is literally sit on the floor (or on a stool), next to the running projector and keep my eyes glued on the failsafe. It won't be very long before the problem makes itself known, even if you have to watch the projector through several runs.
Maybe there's a piece of damaged film? Maybe there's a piece of tape, an old cue or some other junk stuck to the film in a way it shouldn't be? If so, remove the offending material or damaged film.
By this point, you should be down to that one lonely print that just doesn't want to cooperate with you. Again, watch the failsafe and see which of the two sensors don't want to cooperate with you. IF it's the "presence" sensor, disable it. Run on the "motion sensor" only. Remember this: The motion sensor ALSO senses presence in a manner of speaking... If there was no film present, there could be no film motion, could there? You'll be OK for short periods of time. Keep a closer watch on that projector to be extra safe. Just remember to turn any sensors you have disabled back on when you move the film out of that house.
My last point... How can you blame FilmGuard if only ONE of your three projectors is acting up? The logical conclusion is (if your three machines are substantially identical) that there's a problem with the one projector that's giving you trouble.
To be honest, FilmGuard actually IMPROVES the operation of my FM-35 failsafe!
| IP: Logged
|
|
Carl Martin
Phenomenal Film Handler
Posts: 1424
From: Oakland, CA, USA
Registered: Feb 2002
|
posted 01-04-2004 05:28 PM
agreed! in other instances f-g has definitely prevented old/dirty prints from tripping the fm-37.
quote:
Even if the platter roller was wobbling, the lower magazine roller would've been the only roller in the entire chain to possibly have caused a seating problem with the failsafe.
i think the theory was that if that roller siezed up for an instant, it would retard then jerk the film a bit.
quote:
You do FilmGuard your ENTIRE print, right?
of course.
quote:
By the way, can you upload a picture of the leader stock you are using, or at least tell us who your vendor is so we can try to figure out what it is? Also (specifically more important), do you have a stretch of black at the end of your threading leader? It has been widely documented that the older FM35/37 failsafes have had issues with B&W stocks, various black leader and silver retention prints. That coupled with a slightly over-sensitive sensor would make for a solid guess at the real cause of your problem.
i don't have the means to take a picture of it, but i'll try to find out where it came from. there is a stretch of b&w black leader after the countdown. that sounds like it might be the culprit. in the past, there have been minor instances of the film stopping right after startup which were helped by cleaning the failsafe. i always assumed that something about getting up to speed made it more sensitive, but the fact that there is that black stretch there could account for it.
would fullcoat mag be an option here, or will it foul up things even more? we can always switch to color stock.
quote:
Physically flipping that troublesome failsafe with another one in the complex will also tell you a lot when you find that the problem follows the failsafe.
i think we have another fm-37 coming in tomorrow. but since the problem has gone away for now, our troubleshooting options are limited.
quote:
Check the booth lighting. We had a problem with motion-sensor-type failsafes in certain houses that would shut down if you turned the work light on (or was it off?).
in general, i always have the light off when starting. i have left it on a couple of times to keep an extra eye on things lately when it's been going wrong, but it didn't make any difference.
quote:
Filmguard and "Booth Floor Mud Blobs" would have to be pretty evenly applied to probably a foot of film to have any effect... even if this was possible. "Booth Floor Mud blobs" would go by too fast to be noticed (geez... I can't believe I'm hearing this). Seems the cleaner would get all that nasty floor gunk anyway, and to have that much crud on your floor to effect a cue detector must mean you're going through a couple of media rolls a day, eh?
i guess i can rule that one out, then. the media do get quite dirty right at the beginning, sometimes to the point that i've seen little dust bunnies. but no, we don't change them out unusually often. in fact, there's pressure to use them as long as possible to save $.
quote:
While you are at it, make sure all your rollers are aligned perfectly. I have seen many occasions where operators get sloppy and bump rollers out of position.
the bottom roller underneath the fm-37 that sends the film back to the platter (is this called the lower magazine roller?) has always been a touchy adjustment. it very nearly scrapes the pedestal in passing. there may have been compromises made to give it clearance.
quote:
Furthermore, your sensor might be getting weak. They just do that sometimes, even if you have the updated design.
i do think this is part of the problem. a combination of bad stock on the leader, possible roller misalignment, and oversensitive failsafe.
quote:
Again, watch the failsafe and see which of the two sensors don't want to cooperate with you.
it's the motion detector.
i emailed these suggestions to the tech, noting the complete lack of correlation with filmguard. we'll see if this works.
i think component engineering brought the colorado and new mexico ua theaters to his attention. i wish someone here knew what was up with them and what they are doing that masquerades as a f-g problem.
thanks for all your suggestions,
carl
| IP: Logged
|
|
Brad Miller
Administrator
Posts: 17775
From: Plano, TX (36.2 miles NW of Rockwall)
Registered: May 99
|
posted 01-04-2004 05:41 PM
quote:
i think the theory was that if that roller siezed up for an instant, it would retard then jerk the film a bit.
True, but the odds that a roller would spin through an ENTIRE MOVIE, and ONLY seize up at the end of the leader time after time at that exact spot? Nope. That roller just cost your company an unnecessary expenditure.
quote:
there is a stretch of b&w black leader after the countdown
Bingo! There's your culprit. We need to find out what kind of leader you have. Can you mail me a snipet? A foot is plenty.
quote:
would fullcoat mag be an option here, or will it foul up things even more? we can always switch to color stock.
I'll send you a stretch to try if you like, as I haven't been using CE failsafes recently and that's when I started using fullcoat. From what I understand, the trick with the fullcoat is that one side will reflect properly and the other side won't with CE failsafes. So if after putting it on the machine shuts down, simply flip the leader. (Email me privately with your address and I'll ship you a sample.)
quote:
in fact, there's pressure to use them as long as possible to save $.
Tip...cut the rolls in half before you use them. Not only does that produce double the quantity in a box, but it also will use a noticeable percentage less of FilmGuard since you will only be saturating half the quantity. (It also prevents lazy booth staff from trying to run "two shows, then rewind".) Just remember long movies you may not be able to do this with. In that instance, instead of cutting them straight down the center, lay two rolls out on a table side by side and cut off center, so you produce 4 total rolls, 2 for short movies and 2 for long movies.
quote:
the bottom roller underneath the fm-37 that sends the film back to the platter (is this called the lower magazine roller?)
Yes, that is the lower magazine roller. Strong's failsafes are a bit sensitive to that as well. The film must come off of the failsafe roller squarely or you will not get proper operation. Maybe you could recommend to your tech to mount the roller on the wall underneath the port window to aleviate the odd angle.
quote:
i think component engineering brought the colorado and new mexico ua theaters to his attention. i wish someone here knew what was up with them and what they are doing that masquerades as a f-g problem.
It is easier to blame an unfamiliar product than to offer proper support. In reality, they are doing their customers a disservice by not providing the service they should be providing, and they are hurting themselves too, because FilmGuard will keep their failsafes running noticeably longer without hiccups than running without. If they had ever used FilmGuard in their factory, they would know this. Hence, blame the "unfamiliar product".
| IP: Logged
|
|
|
|
|
|
|
|
|
|
|
|
All times are Central (GMT -6:00)
|
This topic comprises 2 pages: 1 2
|
Powered by Infopop Corporation
UBB.classicTM
6.3.1.2
The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion
and agrees to release the authors from any and all liability.
|
Home
Printer-friendly view of this topic