This is topic elctronic intermittent in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by James Robertson (Member # 888) on 07-16-2001, 11:03 PM:
Just how good is the Kinoton electronic intermittent? I'm talking about reliability,maintenance or any problems peculiar to this type of movement.Also are there any other makers of this type of movement out there or are Kinoton on there own?
Posted by John Anastasio (Member # 607) on 07-17-2001, 06:15 AM:
I don't know what the statistics are on those machines, but it seems to me that a stepper motor would be infinitely more reliable than a mechanical maltese cross movement. Besides, when one fails, you just unplug it and stick in a new one. All the retiming adjustments are done electronically.
Posted by Mark Gulbrandsen (Member # 72) on 07-17-2001, 10:05 AM:
James you should really direct this question to Larry Shaw at B,L&S as they distribute them here. I can't exactly remember the statistics he told me a while back in this forum but the failures have been almost zero as I recall, and these machines have been in the studios for going on 12 years. There are many other really nice features about the Kinoton electronic machines too. It goes way beyond just having the electronic intermittent. The only drawback is that the pull down motor is quite expensive to replace whereas a malteese cross movment can be refurbished to new condition quite reasonably.
There are really no other major contenders in the electronic projector catagory right now.Mark @ GTS
Posted by Gordon McLeod (Member # 33) on 07-17-2001, 10:12 AM:
The use of electronic stepper motor intermittents isn't new
Eprad actually took out the first patent on the technology in the early 70's
RCA built a machine that evolved into the Westrex and now is the Christie Epic projector that is electronic.
MaganTech also has the studio machine that is all electronic.
And Sondor as makes a electronic machine
Posted by Larry Shaw (Member # 388) on 07-17-2001, 03:53 PM:
Failures of the intermittent motors are nearly non-existant. The only one I can recall was when a overlength screw was run through a tapped hole in the projector frame with great force such that it bent the motor housing. I'd be hard pressed to blame that on the motor.There is no maintinance to perform, even if you wanted to.
The adjustments one performs with a laptop are only required when a component is changed, typically the sprocket. What is being done then is compensating for any irregularities in the sprocket's manufacture.
Other benefits include continuous remote controllable framing and freedom from damage related to sprocket jams (film wraps and errant cleaning items).
There are J&W specs at http://www.blsi.com/kinoton/technical.htm
BTW, the motor is a specially designed servo/encoder, not a stepper. Kinoton's servos are much more precise than the steppers.
And most of the Sondors in use are actually Kinoton FP-30-EC's made with Sondor's paint job. Recently Sondor has brought out a Sondor-built machine which has some remarkable similarities to the -EC machines they distributed for so long. Coincidence?
-Larry
------------------
Larry Shaw, Chief Weasel (when others aren't in charge)
Boston Light & Sound, Inc.
North American Distributor of Kinoton GmbH
290 North Beacon Street
Boston, MA 02135-1990
Tel: 617-787-3131 x104 Fax: 617-787-4257
E-Mail: larry@blsi.com
Web site: http://www.blsi.com/kinoton
Posted by Gordon McLeod (Member # 33) on 07-17-2001, 04:43 PM:
I shouldn't have lumped stepper and servo into the same lump but the principle is the same. THe disadvantage of a stepper motor is the fact it has a finite # of stepps which limits the amount of error correction it is capable of but I must give the MagnaTech full marks for its registration.
The disadvange of servos is the much higher cost.
All of the electronic movements incorporate a encoder for error correction, some like Kinoton are better than others
Posted by Mark Gulbrandsen (Member # 72) on 07-17-2001, 05:27 PM:
I was told by Ushio that Christie has discontinued the Westrex line of machines and is concentrating on the DLP end of things. Perhaps evidenced by the fact that they now answer the phone as Christie Digital. That sure is a scary propisition if you ask me. Heaven help them when the blower belt in the DLP projector breaks!
Mark @ GTS