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Topic: Cinemeccanica Portacine Revisited

Ian Partridge
Film Handler

Posts: 10
From: Colchester, Essex, England, United Kingdom
Registered: Mar 2016

posted 08-30-2016 04:09 AM

Fredrik, thanks for the information and link to your page about your solution to the flutter problem.

I remember, years ago, lining up to the red dot when threading Westars. We had the instruction manual as the machines were new. Although I cannot remember if this was from following the Westar threading directions.

My Portacine has a red laser sound head about which I need guidance about what type it is and how it works ?

Portacine sound module

The laser module is: " iLEE 0115-01-92-01 B1121 " At present I am using a Cinemeccanica C55PT amp with the internal switch set to 'DIODE'

Ian

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 08-30-2016 05:17 PM

quote: Fredrik Sandstrom
I prefer to set it in the extreme "up" position

My practice, in running CINE Units (and all geneva base movements) Projectors is having the unit in the middle position of the travel so the assembly is in more relaxed position to allow the operator to choose to go up or down, or even the minute framing adjustments when correcting a frame issue.

Placing the operation at it's extreme allows a form of stress to where the assembly wants to move to a more relaxed position.

quote: Ian Partridge
My Portacine has a red laser sound head

More looks like that the filament type exciter lamp was removed and an LED light replaced it, for the pickup is no way an IR Camera, but just a solar, white light reader.

We call it a JAXLight changeout (A unit that just plugged into the exciter lamp socket and a red light passed through the slit lens), where the slit lens wasn't effective enough to handle the red light beam causing a major drop in output voltage off the solar reader. With this drop, the preamps had to be cranked all the way open where one got a lot of noise as the results in the sound.

Red light was effective with the cyan soundtracks, where standard exciter lamps were horrible with the cyan soundtracks, why you got the LED conversion.

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Fredrik Sandstrom
Film Handler

Posts: 63
From: Turku, Varsinais-Suomi, FINLAND
Registered: Mar 2014

posted 08-31-2016 01:09 AM

quote: Monte L Fullmer
My practice, in running CINE Units (and all geneva base movements) Projectors is having the unit in the middle position of the travel so the assembly is in more relaxed position to allow the operator to choose to go up or down, or even the minute framing adjustments when correcting a frame issue.

Placing the operation at it's extreme allows a form of stress to where the assembly wants to move to a more relaxed position.

I was talking about the Portacine specifically. I don't understand what, on that machine, would cause more "stress" in the extreme up position that I favor. If I set it in the middle like you suggest, the film will have some steep turns to go through (and worse still in the extreme down position). The smoothest film path would be achieved by removing the framing mechanism altogether, and something very close to that situation can be achieved by setting it to "extreme up".

quote: Monte L Fullmer
More looks like that the filament type exciter lamp was removed and an LED light replaced it, for the pickup is no way an IR Camera, but just a solar, white light reader.

I've seen laser units just like that, so if Ian says it's a laser I'm sure it's a laser. They are typically used with standard solar cells for pickup.

And Ian, it looks like you have the original mono cell fitted. If you want stereo, you need to change it to a stereo cell, or (better) convert to reverse scan.

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Christos Mitsakis
Expert Film Handler

Posts: 242
From: Ag.Paraskevi, ATHENS, GREECE
Registered: Sep 1999

posted 08-31-2016 04:19 AM

Ian,
The laser is an ACL-9 AUDIO-CINE WALTER VOIGT AG, for Cinemeccanica and Prevost soundheads.

The original web page I think is down but have a look here

Christos

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Ian Partridge
Film Handler

Posts: 10
From: Colchester, Essex, England, United Kingdom
Registered: Mar 2016

posted 09-02-2016 01:12 AM

The laser light beam comprises of a curious mosaic grid pattern and is rectangular, not a slit shape. It appears like a gauze is placed in front of the lens element when the module is lit, but it is an illusion. It is a normal glass lens. A square-shaped beam arrives at the photo diode.

The laser beam arrives at the photo diode.

A similar pattern shows on the front element of the lens tube that is not possible to photograph as the camera gives a scanning line which looks like the conventional slit shape.

Laser sound module.

The rounded glass below the right-angled mirror is divided in the middle ? The Voigt ACL-9 sound module diagram shows a slit-shape, not a rectangle ?

Ian

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Kenneth Wuepper
Phenomenal Film Handler

Posts: 1026
From: Saginaw, MI, USA
Registered: Feb 2002

posted 09-02-2016 09:26 AM

Ian,

Please place a piece of properly tensioned film around the sound drum. Then look at the light image on the sound track area.

Dirty optics or maladjusted scanning beam can cause some strange effects.

There is a slit mask in the optical cell and it can be out of adjustment as well. This whole assembly is very critical to the reproduction of optical sound.

Check in the warehouse for service instructions for a typical sound reader. Your problem may be simply cleaning or improper adjustment. Do not attempt adjustment without the proper film loops and test instruments.

Hope this helps.

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Ian Partridge
Film Handler

Posts: 10
From: Colchester, Essex, England, United Kingdom
Registered: Mar 2016

posted 09-02-2016 03:05 PM

Kenneth you are correct, and Christos is also right that it is a Voigt ACL-9 laser module. I was looking at the diffuse slit image on white leader and not on the soundtrack itself. It seems to be in OK alignment as much as I can tell without test tracks.

Sound slit image focussed on film track.

The sprung roller above the gate is now functioning as it should with the film edges between the flanges. shown in the photo below. I have polished the other rollers in the film path which some had gummed up and dull arbors so they did not spin freely when flicked.

The sprung roller above the gate shown with the film edges now running between the flanges.

Ian

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