Film-Tech Forum ARCHIVE: Closing changeover during lens change

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Posted by Ken Lackner (Member # 1002) on 03-12-2004, 01:39 PM:

I am using Xetron Maxi 12 XPC automation. I've read through the entire manual and there doesn't seem to be a way to get it to close the changeover during a lens change. Is there anything that can be done to modify this automation to get that to happen?

Just so you know, I won't be performing such modifications (unless really really simple), but I'll bring it to the attention of my tech. [Smile]

Posted by Adam Martin (Member # 641) on 03-12-2004, 02:02 PM:

If you're just looking to keep the image from zooming around the ceiling and walls during a turret change, I would just insert a strip of black film or fullcoat into the program timed to cover up the change. I usually kept several laying around pre-made with the lens change cue already on the strip.

Posted by Robert E. Allen (Member # 1351) on 03-12-2004, 03:06 PM:

Or you could send one of your minimum-wage flunkies up to the booth to shut the douser on the lamphouse while the lens changes. Beside, by that time you'll need a focus adjustment anyhow. So be sure to tell them where the focus knob is and what it's for.

Posted by Brad Miller (Member # 2) on 03-12-2004, 03:48 PM:

Robert, running on platters doesn't have the focus drift issues like when running on reels. Also a properly set up turret will not require a focus adjustment after the lens switch. It's called automation.

Posted by Paul G. Thompson (Member # 655) on 03-12-2004, 07:26 PM:

I don't know much about the automation you have, but if there is a manual override switch on the automation unit like most have, the lens cue can also be used to trigger a relay the will reset after a pre-determined time delay. If you find one, just pick up the wires on the manual override switch. There are probably all sorts of ways it can be done in addition to what I just mentioned.

Posted by Robert E. Allen (Member # 1351) on 03-12-2004, 10:54 PM:

OK, who are you, why did you post your picture there and what happened to the REAL Brad Miller?

Posted by Darryl Spicer (Member # 711) on 03-12-2004, 11:55 PM:

quote:
Or you could send one of your minimum-wage flunkies up to the booth to shut the douser on the lamphouse while the lens changes. Beside, by that time you'll need a focus adjustment anyhow. So be sure to tell them where the focus knob is and what it's for.

I don't allow those people to touch anything in the booth.

Posted by Chris Hipp (Member # 1788) on 03-13-2004, 12:15 AM:

You are lucky, some of us have to rely on them to run the booth.

Posted by John Walsh (Member # 168) on 03-13-2004, 01:07 AM:

Closing the c/o shutter during lens change is almost always a function the turret controller does, not the automation. I have seen two automations that did, but it's not the norm. What make of projectors do you have?

There is no fuction in the MAXI12XPC to close the turret between lens changes. I can't even think of a way to 'fudge' it into providing it.

Posted by Daryl C. W. O'Shea (Member # 1303) on 03-13-2004, 01:20 AM:

If the changeover shutter is kept open by a constant current you could just wire it through a relay controlled by the power to the turret motor.

So it all depends on how your changeover works, if the automation can't do it itself and the turret controller doesn't support changeover controls.

Posted by Matthew Nock (Member # 1575) on 03-13-2004, 08:54 PM:

I found a simple way of doing it with our Panalogic automation which you may be able to adapt (I havent used the automation you mention, so I am not sure if this will work).

When the cue arrives for the change over, the automation executes two steps.

1. CNTR-CUE (waits for a centre cue), PIC1-OF (closes changeover shutter), LENS-CS (changes lens format), plus anything else, like lights out..

2. WAIT-2 (waits two seconds - our turrets take 1.8 senconds for a format change), PIC1-ON (Opens the change-over shutter), anything else necessary.

So for a format change, we have two events, that are triggered (the second one is just a little bit after the first).

Cheers,

M@

Posted by Frank Angel (Member # 248) on 03-14-2004, 12:25 PM:

Ken,

What did they do before you got there? Did they let the picture swing across the auditorium like Adam said? Surely they had some means to prevent this....or did they?

The black film slug seems like it would be the easiest way to get around the problem. Or, another solution would be to install a second projector and do change-overs to a proper lens and aperture already in place. [Wink]

Frank

Posted by Ken Lackner (Member # 1002) on 03-14-2004, 02:46 PM:

quote:
Closing the c/o shutter during lens change is almost always a function the turret controller does, not the automation. I have seen two automations that did, but it's not the norm. What make of projectors do you have?

I have a mix of Simplex 1060 and Century (not positive of the model off hand) projector heads. The Simplex heads have the TU2020 turret. One of my former theaters had Simplex Millenium heads with the TU2020 and CNA-150 automation. Closing the changeover was a feature of the automation. With the CNA, there is an option somewhere in the menu to program how long, in seconds, it takes for your turret to rotate. That is how long the changeover would close whether it the lens change was cued or you pressed the manual button.

quote:
What did they do before you got there? Did they let the picture swing across the auditorium like Adam said? Surely they had some means to prevent this....or did they?

Unfortuneately, I have seen the picture swing around on the screen too often. It even happens when I am running the booth if I am not careful to close the manual dowser. Yes, I know the strip of black film would prevent this, and I always do that when I build a film. The problem I see with other films (and I am trying to get rid of this problem), is that for a scope film, the lense change cue will be right before the first trailer, without sufficient black leader to allow for the lense change. So if I press the start button and forget it's a scope film, and if there isn't sufficient black leader, the green band of the first trailer will be swinging around the screen while the lense changes. I usually try to check what format the program is and if it's scope, I set it manually before I press start, but sometimes I forget to do this.

FYI, the whole reason we have this problem is because everything goes back to Flat at the end. Yes, I KNOW this is a bad idea. It has been discussed numerous times before. I have no power to change this. Please do not start ranting on this, that is not why I started this thread.

Posted by Brad Miller (Member # 2) on 03-14-2004, 03:32 PM:

Do you HAVE to go back to flat, say for some ridiculous "on screen advertising" nonsense...or do you just not know how to defeat the automation from doing that?

Posted by Scott Norwood (Member # 30) on 03-14-2004, 04:03 PM:

I'm not sure I understand the problem here. Why not just add black leader to the start of all scope films and put the automation cue on the black leader? Maybe you should just add black leader to the start of _all_ films; a couple of seconds' worth of black isn't going to hurt anyone. $50 will buy you 1000' of FPC mag fullcoat, which should be a lifetime supply.

And, yes, I agree with everyone else that switching formats unnecessarily (e.g. at the start of very show) is dumb and causes unnecessary wear and tear on the masking motors. It also looks bad if you have top masking and the screen appears to get smaller for scope.

Posted by Joe Redifer (Member # 3) on 03-14-2004, 04:06 PM:

Why not add extra (X-Tra?) opaque leader to the start leader? You could have separate flat and scope leaders.

Brad - some theaters go back to flat because they were designed by morons and/or their automations suck ass because the person in charge or purchasing them is a moron.[av=n]

Posted by Steve Guttag (Member # 268) on 03-14-2004, 04:58 PM:

The old Strong SPA-5 and SPA-5A would do the changeover close during a lens change thing...

The Panalogic CA-2000 will do it as well.

One could do it with the Maxi-12 if two lines can be dedicated to the douser...then it i would only be a matter of placing the appropriate cues on the film.

Steve

Posted by Jesse Skeen (Member # 586) on 03-15-2004, 05:28 PM:

"FYI, the whole reason we have this problem is because everything goes back to Flat at the end. Yes, I KNOW this is a bad idea. It has been discussed numerous times before. I have no power to change this. Please do not start ranting on this, that is not why I started this thread."

Aw, c'mon, I WANNA rant about this! That's why I left my last job after all! [Razz]

Posted by Jon Bartow (Member # 241) on 03-17-2004, 08:08 AM:

OK, fairly simple solution for the "have to go back to flat at the end of the show" issue.
The turret and the masking control wires are probably currently both tied to the "Masking" control out of the automation. Simply disconnect the masking control wires and connect them to the "Curtain" terminals. Then your turret is controlled by the "Masking" switch and matrix line and the masking is controlled by the "Curtain" switch and matrix line. You will then have to change some of the diodes on the matrix board (they are just in DIP sockets, no soldering involved)
Then only the masking will move at the end of the show and not the turret. Of course this means there will have to be a "Scope" cue at the beginning of the show for scope movies.
You and your tech should definately be able to do this.
Sorry, with a Century or a Simplex it would be very complicated to get the C/O to close during a lens change with the 12xpc.
Jonthan

Posted by Ken Lackner (Member # 1002) on 03-17-2004, 10:36 AM:

That is brilliant! Why didn't I think of that? I am definitely going to bring this to the attention of my tech.

Posted by Daryl C. W. O'Shea (Member # 1303) on 03-17-2004, 02:39 PM:

That only satisfies a "half to go back to flat" requirement!

Posted by Ken Lackner (Member # 1002) on 03-17-2004, 03:54 PM:

But since the turret will now be staying in scope rather than going back to flat every show, no more green band swinging around on screen during the lens change. That was my goal of wanting to close the changeover during a lens change, and this should satisfy that goal.

Posted by Jesse Skeen (Member # 586) on 03-19-2004, 01:44 PM:

Just make sure those scope lenses don't bang against the side of the projector! [Razz]

And cut those green bands off! [Wink]

Posted by Brad Miller (Member # 2) on 03-19-2004, 02:26 PM:

Cut the green bands off? What's the deal, afraid that nice bright green screen will show off dirt and scratches? [Razz]

Posted by Adam Martin (Member # 641) on 03-19-2004, 02:28 PM:

Nah ... he figures if he's gotta make the slides bigger than the movie by always raising the vertical masking for them, he might as well make the trailer soundtrack smaller than the intermission music by chopping off the beginning. [Razz]

Posted by Ken Lackner (Member # 1002) on 03-19-2004, 03:40 PM:

I shouldn't even comment here, but what on earth does cutting the green bands have to do with my original question? BTW, my company leaves green bands on.