Film-Tech Forum ARCHIVE: Component Engineering Automation Query

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Posted by Leo Enticknap (Member # 534) on 04-02-2001, 01:56 PM:

We have a Component Engineering TA-10 automation system. When running silents, the 'motion detect' sensor will not work at speeds below 20fps. At 20 it flickers on and off: above that it's fine.

Is this something I'll just have to live with, or is there a way of getting it to detect motion at lower speeds? With rare archive prints, it would be nice to know that an instantaneous shutdown will happen in the event of any film jam, rather than having to override the automation for these shows.

Posted by Aaron Sisemore (Member # 145) on 04-02-2001, 03:53 PM:

If you are running silent features, I would assume that the projector(s) are being attended to at all times during the show? if so, why not just disable the motion sensor with the little switch on the left edge of the TA10 circuit board?

Aaron

Posted by Leo Enticknap (Member # 534) on 04-02-2001, 05:09 PM:

Of course someone is there during a show. Even so, in the 5-10 seconds it takes to respond to something going wrong, quite a lot of film could get damaged, especially when it's old, brittle acetate.

I have been disabling the motion sensor so that at least we have presence detect operating - but motion detect would be an additional safeguard and I'd be interested to know if there's a way of enabling it at the lower speeds.

Posted by Aaron Sisemore (Member # 145) on 04-02-2001, 07:44 PM:

What projectors are we talking about here? Most projectors have a flywheel which even if the motion detector DID properly engage, the projector will come to a stop rather slowly, damaging more film in the process ( unless the motor is manually grabbed and braked quickly)...

Aaron

Posted by Paul G. Thompson (Member # 655) on 04-02-2001, 08:38 PM:

I would recommend you contact Component Engineering about this matter.

Posted by John Pytlak (Member # 331) on 04-02-2001, 08:39 PM:

Bill Purdy, are you reading Film-Tech this week?

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Randy Stankey (Member # 64) on 04-02-2001, 10:54 PM:

There should be two switches on the motherboard of the automation controler. They enable/disable the two parts of the faisafe sensor. One for "motion" and one for "presence". (I'm assuming that since the film is silent you are running acetate film, right?) An LED next to the switch should alert you that you have disabled one or more failsafe functions. Turn off the motion and you'll STILL have failsefe protection if the film breaks or "jumps the track" on the failsefe's roller.

Many theatres only have failsafes that detect presence anyway. Since this is going to be an attended projector I don't think you'll have any problems to begin with. If, by chance, something did go wrong you'd still be there to catch the problem. The failsafe is only giving you that "extra margin" of safety.

If I remember my specs correctly the "flicker" caused by the sprocket holes going by the sensor is what the detector "sees" to sense film motion. As far as I know, the "rate" of flicker that the thing wants to see is hard-wired into the device. I suppose Bill Purdy or one of his guys will have to answer this question in detail.

Just think, back in the "old days" most projectors didn't even have falsifes! The only reason they are there is because most states have some kind of law that says they have to be there if the projector is not attended 100% of the time. This is basically an outgrowth of "platter technology" which allowed people to start the machine and just walk away.

1) You don't make mistakes... that's why you are a member of Film-Tech, right?
2) Your booth is attended 100% of the time. (Or at least 99.5%)
3) You still have presence detection.

I don't see a problem here.

Posted by Bill Purdy (Member # 202) on 04-03-2001, 10:38 AM:

Yes, John, I am awake this week, just sleepy.

Leo,
I am a little surprised that it is dropping out at the 20 frame rate. It is supposed to work to down around 12 or 14. This, however, is determined with a simple R/C time constant and is therefore subject to variations. So, I have two thoughts for you. First, look at your sensor assembly and note if there is a red dot on it, and if there is, look up at the bottom of it and see if there is an eight pin IC package. Then look at the support roller. It should have "Vee" shaped grooves below the scanning areas If all this is so, then you have the latest version. If not, you may want to consider the upgrade which is much more stable and forgiving. We sell these directly to the end users for US$56.00 and there is a $15.00 refund if you return the old assembly.

Possible fix number two requires the change of one resistance value. We have a drawing for this and I shall e-mail it to you in JPEG format.

Please don't hesitate to contact us if you have any other problems.

------------------
Bill Purdy
Component Engineering

Posted by Leo Enticknap (Member # 534) on 04-03-2001, 02:43 PM:

Many thanks for all your suggestions.

We do have the grooved support rollers.

I've now experimented with the other projector (the silent we ran last week was not an archive print and fitted onto a single 6,000ft spool, so only mech was needed) and found that it will detect motion correctly right down to 16fps (the slowest our inverters go).

So I guess it must be a time constant issue with that one machine.

Incidentally, the projectors are Cinemeccanica Vic 5s.

Many thanks for everyone's help...

Posted by Brad Miller (Member # 2) on 04-03-2001, 03:37 PM:

Bill, if you will also email that file to me, I will post it here on this thread. That way if someone is searching the archives in the future having this same concern, the answer will be right there.