Film-Tech Forum ARCHIVE: Aperture Plate Issue

This is topic Aperture Plate Issue in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Greg Routenburg (Member # 1742) on 07-20-2003, 12:45 AM:

First, I'd like to open this thread by expressing my absolute disgust for the response to this issue by the management team of the theatre in which I work. As of the 2nd show this afternoon, there was a large dark band on the right hand side of the screen covering from the edge to about 1 meter into the screen. The managers response to this issue was "oh it's not that bad" and instead of calling a technician figured it could wait until the General Manager worked again on Monday. Monday, can you believe it. That's a minimum of 7 shows with a giant piece missing from the picture. When I arrived at 6 to start work, tonight as an usher, it was brought to my attention so I looked at it and was completely stumped. I'm hoping someone can help me out as I couldn't respect myself if I let this continue. Here's the scoop as it's been told to me and as I've observed it...

First, we're running a Simplex Millennium with a dual aperture configuration. The print running at the moment is Flat.

The first show ran perfectly according to the projectionist that worked today. The problem was only from the 2nd show on.
Upon closer inspection it was discovered that the aperture plate was offset horizontally so that it was cutting off part of the frame. I tried to move the aperture plate by hand but it was already as far out as it could go. I tried switching from flat to scope and back again but the alignment was uneffected. Has anyone encountered this problem before and more importantly, does anyone know how to fix it? Any help would be greatly appreciated.

I still can't believe they were going to leave it until Monday. Inconceivable.

Posted by Darryl Spicer (Member # 711) on 07-20-2003, 01:00 AM:

If I read your post correctly you are saying that the screen is blank or dark on the right side. If so pulling the plate out will not correct the problem. The plate has to push inward. Did you check to make sure that the screw that holds the plate into position has not gotten loose. If it gets loose enough the plate will go past its stop position a bit causing what you have described.

Posted by Greg Routenburg (Member # 1742) on 07-20-2003, 01:59 AM:

Looking at the projector from the front, the plate is too far to the right. The mechanism that moves the aperture plate is as far left as it can go. I know what you mean though. I'll take a closer look at it tomorrow again.

Posted by Darryl Spicer (Member # 711) on 07-20-2003, 02:12 AM:

the thing is that if the plate is to far inward. torwards the inboard of the projector you would be getting darkness on the screen image on the left side with some spill over on the right. if it was to far outward you would get darkness on the screen on the right and spillover on the left with probable timecode and soundtrack hitting the wall.

Posted by Tim Turner (Member # 1109) on 07-20-2003, 10:07 AM:

Greg, you remind me of ME everyday when I'm running around the booth trying to figure out why stuff is still broken years after I report them to the managers.! [Big Grin]

Its entirely fustrating and embarrassing to the Projectionist, because the audience is thinking that the Projectionist is the one thats the idiot. [Mad]

Anyway as Darryl said check the screw it may be loose. Also find out if that aperature plate is even in correctly. Or if it was ever replaced cause it might be the wrong size.

Posted by John Anastasio (Member # 607) on 07-20-2003, 10:18 AM:

I had a problem like that once and the culprit was the stop screw on the turret. It loosened and sent the entire picture off-center on the screen. I'm not familiar with the Simplex, but Christies with turrents can do that.

Posted by Scott Norwood (Member # 30) on 07-20-2003, 10:36 AM:

Are you sure that the issue is with the aperture plate and not with the masking? It's probably worth pulling the plate out completely to ensure that the picture really does fill the width of the screen and that the masking is adjusted properly.

Posted by Darryl Spicer (Member # 711) on 07-20-2003, 11:19 AM:

The interesting thing that he mentions in his original post is that everything was fine the first show. It depends on the type of turret version for the stop screw issue. If it is the newer version that you open and close by hand that is not as big an issue as the ones that open electronically.

Posted by Michael West (Member # 428) on 07-20-2003, 11:28 AM:

greg;

having the same type of projector and from what you have described i would agree that the aperture adjustment is out and if that is the case, at the aperture 6 cm below the strap tension knob a 5/64" (very small) hex key will adjust this to the left or right. and/or depending on the lens turret that can also be adjusted. or it could be masking if it moves side to side. or in the more extreme case the projector was knocked out of place.
hope i helped!

Posted by Greg Routenburg (Member # 1742) on 07-21-2003, 12:33 AM:

Thanks guys for your input. A technician was called in today and fixed it. As it turns out it wasn't the aperture plate at all. From what the day time projectionist described one of the spring loaded film runners came loose at the bottom of the trap and sprung over covering part of the aperture. I guess I'll have to look a little closer next time. Thanks again.