my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Questionable Change-over logic (Page 1)

This topic comprises 2 pages: 1  2

Author Topic: Questionable Change-over logic Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 02-25-2003 02:12 AM                        At the moment I am modifying (in my head) an installation which for some unknown reason has two change-over switches (momentary push-buttons) on each projector console -- the main change-over switch which is what you'd expect: it opens the c/o shutter on its local machine and closes the c/o shutter on the outgoing machine and switches the CP55 preamps. Fine. But the second switch does just the opposite, for which I cannot find any logic for such a function. Why would anyone want to switch sound and picture to the other machine if you are not standing at it? It is useless. On occasion the operator would miss a motor cue and have to go to black. He instinctively pushes the "reverse" button. Well, yes, it does shutter his machine, but it also opens the shutter of the outgoing reel on the other projector; either way he's screwed. So I want to change that switch to a complete KILL function. Hitting it will close the local machine's c/o shutter but not open the second machine's. But here's the question. I also want that switch put the CP55 in its MUTE state -- in other words, this will be an emergency or "Panic" switch, when the best thing would be for everything to stop in the theatre. But here's the dilemma -- it would be very easy to have a contact on the switch activate the MUTE function. BUT, the question is, will pushing the main change-over switch, which normally toggles the projector selector in the CP55 (Prjt 1 or Prjt 2), will that automatically defeat the MUTE and resume sound from whichever projector's c/o switch was activated? OR, do I need an additional contact to actually unMUTE the processor AND then activate the projector sound? I will have another set of contacts on that switch if it is necessary because I am also divorcing the shutter c/o from the console switch and leaving only the audio c/o on it. In a rep house we need to be able to lag the sound change-over after the picture in order to catch those last 20 frames of sound which many times has been crucial. If picture and sound change-over are simultanious and married on one switch, you can't do that lag. I'm actually dragging out the ole tried and true foot switches for the picture c/o. Anyone know off-hand if the CP55 logic needs two contacts -- 1)to unmute a muted state AND then an extra pulse to activate whichever preamp? OR (and this is what I hope) will the mute state unmute by virtue of either projector being called? Sorry guys, I know this sounds rather rudimentary, but I am drawing this on a napkin in my jammies and I don't have a CP55 manual here. Frank  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 02-25-2003 02:16 AM                     If I remember correctly, the one mute control will mute and unmute back and forth every time you hit it. Also, I do believe if you pulse the desired softkey it will force itself out of mute. So ideally you need to take your master sound changeover button and wire it through a 4 position selector switch so you can tell it that once you initiate the changeover to select a certain format. That way you don't have to worry about whether the mute is on or off from your "panic" button.  |  IP: Logged Daryl C. W. O'Shea Film God Posts: 3977 From: Midland Ontario Canada (where Panavision & IMAX lenses come from) Registered: Jun 2002 posted 02-25-2003 02:45 AM                        Brad's right about the mute button. Pulsing the same contact will turn it on or off. Select any format (even the current one) will un-mute the processor. Now if I remember correctly (and if you're lucky), selecting another projector will also un-mute the processor, but I could be mistaken. If it doesn't the easiest place to wire a four position switch would be right at the processor. If you want to be able to switch from 1->2 and 2->1 using the 'panic' button you'll need two 4 position switches (or a single DP4T) and some diodes.  |  IP: Logged Carl Martin Phenomenal Film Handler Posts: 1424 From: Oakland, CA, USA Registered: Feb 2002 posted 02-25-2003 06:14 AM                        i've never run c/o but it seems like the setup as it exists could be useful if, say, a print comes in without existing cue marks. rather than scribing cues or otherwise marking the image area, little flags could be put on the edge of the film. if you stand at the projector whose reel is ending, you can then changeover to the other projector when you see the flag enter the filmhead, or hear it go through the gate, depending on its placement. you'd probably also want motor switches for both projectors in each position. even if the print has cues, i would think this method might make for more frame-perfect changeovers. carl  |  IP: Logged Joe Beres Jedi Master Film Handler Posts: 606 From: Minneapolis, MN, USA Registered: Nov 2000 posted 02-25-2003 10:11 AM                     Frank, I wouldn't call your system useless. It is really helpful in certain applications. I have a similar set-up here, and it comes in handy in two situations. It really helps when you are aligning two images and setting focus. Being able to switch back and forth quickly and A/B makes for fast work. Also, I periodically run shows, similar to Inside the Actor's Studio, in which I run short, mid-reel clips. I can put easily seen cues on the edge of the film, and start and stop them without shuffling over to the other projector. It's a convenience that helps me run a high-profile, high-stress event more smoothly. It isn't a necessity, but it is really nice.  |  IP: Logged Christopher Seo Jedi Master Film Handler Posts: 530 From: Los Angeles, CA Registered: Jun 99 posted 02-25-2003 11:14 AM                     There is some merit to having a "reverse" changeover switch at each projector, which is the case at the theatre I work, but I still agree with Frank that an all-close, all-mute switch is also much needed. For example, while the last reel of a show was playing I have threaded up a reel of the next (i.e., different) show on the other projector and started running it through, intending to do a quick focus/framing check during intermission. Well, since the only way I can end the current show is to change pix and sound over to the other machine, I must resort to pulling the exciter lamp so my test reel doesn't end up blasting into the auditorium. As Frank said, an all-close, all-mute button would also be handy in case of a missed changeover...  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 02-25-2003 02:08 PM                        Frank--I _like_ having the ability to changeover from either machine while standing next to either machine. It's useful when threading (to select the other machine without having to walk around) and in case one accidentally hits the c/o button too soon. The "all close" idea is interesting, but it doesn't seem nearly as useful and it seems like it would confuse a projectionist who isn't familiar with the venue. Do you really have that many problems with missed changeovers? If it happens more than once a year or so, then you probably have bigger issues.... In any case, please leave a big note in the booth explaining how the "all close" system works. Some relief operator will thank you for it.  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 02-25-2003 03:47 PM                    Strong's VIP-based studio projection system has "anti" changeover buttons, too. They come in handy in some instances but I never found it useful enough to install similar buttons in my own facility. One use is simply to kill the show at the very end, something normally done by switching to the non operating machine. However, using this technique to kill something still running doesn't really work with Dolby Digital because the digital source won't switch to the non running machine (at least that was the logic on the CP500D. So an actual kill (all close, all mute) button might be useful. But undoing the mute by pulsing the format button will cause a tiny disruption in sound if done on this CP so you wouldn't want such pulsing to be done on each C/O whether needed or not. But the analog processors may not have the same problem.  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 02-25-2003 08:38 PM                     I'm sure this doesn't help Frank (because has has no automation controller), but in our setup, the changeover button acts as a kill switch if its pressed a second time. This is a handy bit of overloading. We also have a 10-button control panel near each projector (as well as in other parts of the booth) that lets you access all the automation functions, including changeovers, sound format selection, digital override, volume changes, voice-of-god, kill switch, etc. --jhawk  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 02-25-2003 09:27 PM                    in our setup, the changeover button acts as a kill switch if its pressed a second time. This is a handy bit of overloading. I don't like that idea as an inadvertent bounce would kill the show not to mention that if one ever suddenly has a changeover sticking (particularly the closing one that you're not near) you would not be able to give it an extra zap and a split second glitch turns into the several seconds it takes to get to the other machine.  |  IP: Logged Daryl C. W. O'Shea Film God Posts: 3977 From: Midland Ontario Canada (where Panavision & IMAX lenses come from) Registered: Jun 2002 posted 02-25-2003 09:34 PM                        All this brings up why I prefer seperate sound and picture changeover controls (especially c/o controls that you can mute). In the rare event that you muck up the changeover you can mute the sound and do a picture changeover to the incoming machine without opening (or quickly closing if already open) the hand douser on the incoming machine. When the picture finally hits the gate on the incoming machine you open the douser and complete the sound changeover. No stopping the show, no showing the outgoing tail, and no loud noise in the auditorium.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 02-25-2003 11:47 PM                        Damn, I love this forum. All good points. You're right, the need for a kill switch doesn't happen very often, but still, when it does, I really wish the kid had an easy way of lessening its impact in the house. Without it, you wind up with a real mess in the house (ever hear what a tail running out sounds like with four 4000w subbass Community bins in your system?....it ain't a pretty sound!) And you're right Joe, I didn't remember the convenience being able to switch back and forth between two machines when aligning light output and uniformity. I think the final design will be to keep the back and forth ability but add an ALL KILL button too. And, of course, there was no question about separating sound and picture c/o switches....any of you guys ever use the foot peddel switches? --you really get to put your whole body into the change-over! Thanks guys. Frank  |  IP: Logged Daryl C. W. O'Shea Film God Posts: 3977 From: Midland Ontario Canada (where Panavision & IMAX lenses come from) Registered: Jun 2002 posted 02-25-2003 11:55 PM                        quote: any of you guys ever use the foot peddel switches? --you really get to put your whole body into the change-over! Yup -- at a couple drive-ins. Some with sound changeover on the floor too. Foot switches just make it too easy, you don't even have to get out of your chair to do the changeover.  |  IP: Logged John Anastasio Master Film Handler Posts: 325 From: Trenton, NJ, USA Registered: Sep 2000 posted 02-26-2003 02:30 AM                        I remember the foot pedal switches. It was neat stomping on those things. I haven't seen them in decades.  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 02-26-2003 08:43 AM                        Steve--is that the setup with the jumbo-size red and green buttons on the projector base? If so, then I didn't realize that it was a standard configuration from Strong...I had assumed that it was something clever that the installation company had done. Kinoton FP30s (and maybe other models) have two changeover buttons that serve the same purpose, too, though they are annoyingly located on the front of the machine. I like having footpedals for picture and pushbuttons for sound (probably because that's the arrangement that I started with), but that setup seems to be uncommon in newer installations. What I can't stand is when someone has decided to mount switches or pushbuttons which don't control projector motor or changeover on the wall or projector base near the actual projector controls. The Cape Cinema (see pic gallery) has the "curtain" pushbutton located next to the "changeover" pushbutton. Guess who hit the wrong button one night....  |  IP: Logged

All times are Central (GMT -6:00)

This topic comprises 2 pages: 1  2

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

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.