Film-Tech Forum ARCHIVE: shaky picture on Century LCACSAW projector

This is topic shaky picture on Century LCACSAW projector in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=006419

Posted by Shane Hoffmann (Member # 1620) on 07-31-2004, 02:01 PM:

Right now we are running the Bourne Supremacy on this projector. The picture is very shaky (other than the intended camera work-- even the green band on trailers looks terrible).

It appears that the pad arm assembly that clamps the film against the intermittent sprocket is not tight against the film. I tried to adjust it, and I am assuming that it should be tightened, and it helped somewhat, at least enough for us to run the show, but there is still a slight noticeable shake.

Edit: I just tightened it as far is it goes, but the pad still moves a tiny bit.

Is there anything else that could be contributing to the picture? The gate assembly all seems to be in order... I tried adjusting the shutter, and I want to be sure that that's my problem.

I could use the help very quickly. Thanks a lot!

Shane

Posted by Ron Yost (Member # 1850) on 07-31-2004, 02:46 PM:

Since no one else is answering and you need help fast ..

Search this forum for the following thread (almost the same as your thread title):

Shakey Picture on Century Projector

(If I knew how to post the direct link for it I would.) [Big Grin]

BTW: The clearance between pads and their sprockets should be, generally speaking, two-thicknesses of film. Tighter than that will only wear out the pads and needlessly wear the edges of the film.

Are you sure there's OIL in the intermittent?

Is the lens and/or turret clamped securely?

Gate adjustment is very important too, but I don't 'know' Century's, so can't comment .. the referenced thread gives some advice, and I know there is much more advice in the wealth of archived posts here. You might have to search a bit.

Hope you find something that works for you. [Smile]

Ron Yost

Posted by Mark Gulbrandsen (Member # 72) on 07-31-2004, 06:15 PM:

It would help to know which direction the image is shaking.... Vertically or horizontally? While the pad rollers should be adjusted for two film thicknesses the intermittent pad should actually contact the sprocket(or film) and the spring thats used to load it should conpress just slightly, perhaps 15 to 20%. There should be a small detent that the set screw locks into on the pad roller mounting stud. So remove it completely from the movement and look for that indention. Be sure the tip of the set screw is seated in the indention when you tighten it back down. This sets the position, and spring loading correctly. If it is in the indention the pad might be defective..... I've seen this happen just once where the intermittent pad arm casting cracked internally at its bore.

With the lens sliders this typically happens in the horizontal aspect and iss caused by the motor mechanism not traveling over far enough to slightly stretch the spring that connects the slider mechanism to the motor drive mechanism. What happens is someone forces it over and dislocates the connector that rides in the timming belt inside. Other than that your problem could be a loose intermittent sprocket set screw or a bad movement.

Check for .25" clearance between the flat part of the gate that the curved runner mounts to and the outer studio guide. This way you know the gate tension is at factory spec. Also, are the trap bands ok?

You should have your service tech remove that lens changer as the motors and parts for them are long obsolete, junk the Magnacom too. We found one in the shop the other day and it went in the trash. The best thing is to just use it as a single lens mount projector, or have your tech install the Kelmar lens turrett kit. This can be done right in the booth! The Kelmar is far superior to that slider rig you have there.

Mark @ CLACO