Film-Tech Forum ARCHIVE: Stretched Text

This is topic Stretched Text in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Wilson J. Manceaux (Member # 2428) on 05-17-2004, 02:57 PM:

Hello all. Our Club restored an Old High School auditorium and made it into a movie theater. We've been showing movies for about 2 1/2 years on an Century C projector. A few weeks ago, I noticed the text on the screen appears to have "tails" in other words it looks like, if you took a picture of the lights of a moving car, at night with a camera and slow shutter. White text is worse. What would cause this effect?

Posted by Mike Olpin (Member # 1115) on 05-17-2004, 03:00 PM:

You are noticing a shutter ghost, which means your shutter timing is off, or possibly the shutter belt has snapped.

Basically, the shutter movement should completely block the light while the intermittent advances the frame. In your case, the intermittent has not completed (or has just started) the pull down sequence before the shutter has closed off the light.

Click over to the Manuals section of this website and download a copy of the Century C manual. Inside of it you will find instructions on how to time your shutter. I recommend printing a copy out and keeping it in your booth.

Posted by Scott Norwood (Member # 30) on 05-17-2004, 03:07 PM:

Centurys don't have shutter belts. [Smile]

If the shutter timing is off by a slight amount, it can be corrected by twisting the "shutter" knob on the front of the machine (the top one that says "shutter," not the one by the lens that says "focus").

If the timing is way off, download the manual from this site (if you don't already have one) and follow the procedure that it describes. It requires a screwdriver and is very simple.
Also, check the port glass and make sure that both it and the lenses are clean and free of oil spots and fingerprints. (Don't clean lenses if they don't need it, however.)
Please send in photos of your theatre for Brad to post here!

Posted by Mike Olpin (Member # 1115) on 05-17-2004, 03:13 PM:

A shutter knob? Cool!

Technicaly Scott beat me to it! He posted while I was still editing my post! [Big Grin]

Posted by Wilson J. Manceaux (Member # 2428) on 05-17-2004, 03:15 PM:

Thanks to this wonderful forum I was able to download the Owners manual and looked up "Timing the Shutters" I'll try it, Boy do I have a lot to learn.

Posted by John Hawkinson (Member # 1135) on 05-17-2004, 03:29 PM:

Note that not all Century Cs have exterior shutter timing knobs. On many, the knob is inside the driving side door and can be tricky to adjust because of the moving parts.

--jhawk

Posted by John Pytlak (Member # 331) on 05-17-2004, 03:45 PM:

"Travel Ghost" will usually be most visible along the right hand side of the image, at either the top or bottom of the image. As you found, it is most noticeable on white titles against a black background.

The shutter blade needs to block the light while each film frame is being pulled into position in the gate. For the most common 4:1 Geneva-type intermittents, film is moving for about 90-degrees of rotation of the shutter shaft. If the shutter is not "timed" or synched properly with the film pulldown, you get the streaks above (shutter closes late) OR below (shutter opens early) the image. If the shutter blade is not wide enough, you get steaks above AND below the image. If the streaks come and go, there may be some play in the gear train between the shutter and intermittent.

Posted by Brad Miller (Member # 2) on 05-17-2004, 10:21 PM:

quote: John Pytlak
"Travel Ghost" will usually be most visible along the right hand side of the image

What projector are you referring to? Top or bottom yes, but right side?

Posted by John Pytlak (Member # 331) on 05-17-2004, 10:43 PM:

With a "fan" type shutter such as in a Century SA, I've found the ghost is usually more severe along the right side.

Posted by Brad Miller (Member # 2) on 05-17-2004, 10:46 PM:

That's got to be a pretty minor difference, but I know what you are saying.

Posted by Mark Gulbrandsen (Member # 72) on 05-17-2004, 11:02 PM:

"With a "fan" type shutter such as in a Century SA, I've found the ghost is usually more severe along the right side."
_________________________________________________________________

John is correct on that statement as the shutter blade is narrower at the optically opposite side of the blade. If the lamp is improperly focused it can be very niticable as the cone of light is larger than that side of the blade is capable of completely covering up. This was very noticable on certain older Xetron lamphouses.

I've always said that if there is travel ghost in a projector then there is a problem in the machine....

No European projectors employ a shutter adjuster knob of any type and no user timming adjustment is really needed on any projector for that matter. If something is worn or askew enough for the timming to be noticably off then something is either wrong with the mechanism or someone was messing around with that un-needed shutter timming knob. This is so typical on a Simplex as you will find that knurled knob on top way out of wack all the time!! No one knows what it does and no on can remember when they are told... best to leave it off the machine completely as the Europeans have realized whilst us Americans have continued to include these un-needed knobs for whatever reason.

Mark

Posted by John Walsh (Member # 168) on 05-18-2004, 08:51 AM:

-"With a "fan" type shutter such as in a Century SA, I've found the ghost is usually more severe along the right side."-

I agree... I think it is very noticeable with Ernamann 15's, to the point that there seems to be very slight flicker on one side at all times.

I like shutter adjusting knobs. You can set the shutter "static-ly", then tweek it. I like V8's but one of my favorite things is NOT reaching in there to nudge the shutter. On Ernamann 15's, sometimes the squeeze fitting clamps onto the shaft even when the screws are only lightly tightened.... you then have to yank hard on the shutter to free it, spoiling the setting you almost had.

Posted by Frank Angel (Member # 248) on 05-18-2004, 09:42 AM:

quote:
Europeans have realized whilst us Americans have continued to include these unneeded knobs for whatever reason.

1) Americans don't like change -- how long have car manufacturers kept the headlight control on a separate switch and not tied to the ignition switch, even though there is hardly ever a situation where one would want the headlights on while the motor is off? But originally the lights were controlled by a separate switch and that's the way they kept it, all the while knowing that arrangement, where headlights can remain on without benefit of the alternator can and, usually does, at one time or another, result in a serious problem (a dead battery). Simply changing the traditional arrangement and passing headlight control thru the ignition switch over the years before the very recent introduction of sensing headlights would have prevented millions of dead batteries. It was never done (anyone want to put forth a theory about a car manufacturers/battery manufacturers conspiracy theory?).

2) Americans like knobs (and flashing indicator lights)....makes a piece of equipment look like it's somehow better if it's got more bells and whistles; whether or not they are of real benefit is of little consequence -- they are usually perceived of as a benefit.

Posted by Andrew Lee (Member # 1330) on 05-18-2004, 12:39 PM:

This is so true. I have always been intrigued by the fact that people purchasing things like cars, A/V equipment, and assorted gadgetry are attracted to more "knobs and buttons" that are never utilized. On the other side of the coin, there is a movement in the home theatre and screening room industry to simplify. People with money to spend in this area only want the following: on/off, volume, source, and channel. They are paying big bucks not to have to deal with bells and whistles.

Posted by Michael Schaffer (Member # 1204) on 05-18-2004, 03:18 PM:

quote: Frank Angel
how long have car manufacturers kept the headlight control on a separate switch and not tied to the ignition switch, even though there is hardly ever a situation where one would want the headlights on while the motor is off?

A typical situation where the headlight switch comes in handy is when you drag a body into the woods to bury it at night. You don`t want the motor running all the time but you still need some light.

Posted by John Pytlak (Member # 331) on 05-18-2004, 03:31 PM:

quote: Michael Schaffer
A typical situation where the headlight switch comes in handy is when you drag a body into the woods to bury it at night. You don`t want the motor running all the time but you still need some light.

And to think that I wrote a personal recommendation to allow you to move to the United States. [uhoh]

Posted by Alan Haigh (Member # 1781) on 05-18-2004, 03:57 PM:

Yes he has a sense of humour - you can't possibly let him in! [Wink]

Posted by John Pytlak (Member # 331) on 05-18-2004, 04:15 PM:

With his sense of humour, maybe Michael is a decendent of the "Laughing Murderer", Crown Prince Wilhelm:

http://www.firstworldwar.com/source/verdun_crownprince2.htm

quote:
The newspapers at home were cruelly unjust to me in this, representing me as responsible for all the bloodshed. They even called me "the laughing murderer of Verdun."

Our soldiers at the front knew better. A dozen incidents showed their affection for me, and their knowledge as to where the responsibility really lay.

Posted by Brad Miller (Member # 2) on 05-18-2004, 04:39 PM:

quote: Michael Schaffer
A typical situation where the headlight switch comes in handy is when you drag a body into the woods to bury it at night. You don`t want the motor running all the time but you still need some light.

Wow Mike, for once I couldn't agree more with you. Sometimes the moonlight just doesn't do the job.

Another good use is to use it to photograph old theaters at night when there is no street lighting bright enough to get a shot for Cinematour. The fact that is looks suspicious enough to get the cops harassing you adds to the fun.

quote: John Pytlak
And to think that I wrote a personal recommendation to allow you to move to the United States.

Wait, that was YOUR fault??? Oh my. Joe will be along to ban you shortly. [Razz]

Posted by Michael Schaffer (Member # 1204) on 05-18-2004, 05:13 PM:

Sorry to upset you - that is just our standard procedure for employees who don`t load the DTS discs in the player.

Posted by Joe Redifer (Member # 3) on 05-19-2004, 01:46 AM:

BANNED![av=y]

Posted by Wilson J. Manceaux (Member # 2428) on 05-19-2004, 09:04 AM:

I haven't had a chance to adjust the shutter. Our Theater is being used for a Beauty Pageant this week. Friday we'll show Shrek 2 maybe I'll get a chance to play then. We have a simple web page http://web.infoave.net/~tracycitybc I'll add some more pictures soon. PS I'm still trying to figure how headlights wired through the ignition switch will fix my problem?

Posted by Michael Schaffer (Member # 1204) on 05-19-2004, 04:40 PM:

You can`t expect any more responses to your question until you post pictures of the beauty contest.