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Topic: Vic 5 at Silent Speed

Tom Sauter
Expert Film Handler

Posts: 163
From: Buffalo, NY, USA
Registered: Sep 2000

posted 07-13-2001 08:16 AM

A venue wants to make a conversion for a Cinemeccanica V5 and Christie AW3 to show old silent films at the correct speed. Assuming this is all on safety stock, for purposes of discussion only how would you make the conversion?

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 07-13-2001 08:33 AM

Since it is 3 phase motor on the projector a motor drive control (frequency converter will do the job.
Contact Entertainment Equipment Corp for a price
as it would be a simple permanent dial up speed changes

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Richard Fowler
Film God

Posts: 2392
From: Ft. Lauderdale, FL, USA
Registered: Jun 2001

posted 07-13-2001 06:22 PM

If you plan to show at silent speed and have enought lamp power, Cinemeccanica makes a 3 blade shutter to minimize flicker at silent speed. I have done many silent festivals with a V-5 set up, with frame rates of 16 - 20fps using a C mount d.c. drive motor with tachometer.
The suggestion of Gordon of using a frequency invertor control with a 3 phase invertor motor ( vs the Cinemeccanica motor ) is a good way to go also since many controls allow you to set up a preset dual, sound / silent speed settings.......many of these items are available at W.W. Grainger or B&B motors.

Richard Fowler
TVP-Theatre & Video Products Inc.
Miami, Florida U.S.A. www.tvpmiami@tvpmiami.com

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 07-13-2001 06:50 PM

The one I use the most at film labs is the Allen Bradley unit.
The projector already has a 3phase motor on it so it should be able to program with in its ratings. If not a Reliance 3 phase motor is very popular
the desired speeds would be
24fps=1800rpm
18fps=1350rpm
16fps=1200rpm
Since the current draw increases under a constant load as the motor is slowed down A larger motor might be needed but there is only one way to find out
I know on a Vic 8 I have used the regular cinemecanic 3phase 1800rpm motor

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Dennis Atkinson
Expert Film Handler

Posts: 129
From: Birch Run Michigan
Registered: Feb 2000

posted 07-13-2001 07:30 PM

Please don't be cheap and think you don't need a 3 blade shutter.
It cuts down the light out put by aprox 30% but the lack of flicker and headaches will be worth it.
Will you be cutting a new plate? What about the lens length?

I would check to see if the distributer(s) of the silent films allow for platter use. Many will not.

Dennis

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Tom Sauter
Expert Film Handler

Posts: 163
From: Buffalo, NY, USA
Registered: Sep 2000

posted 07-15-2001 06:24 PM

I'll cut a new plate for sure, if I end up spending the bucks on a 3 blade shutter. Guess I can avoid fixing those blown horns, now too

Thanks for the tips.

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Josh Jones
Redhat

Posts: 1207
From: Plano, TX
Registered: Apr 2000

posted 07-16-2001 01:11 AM

Now I personally have never seen a Vic 5, but be certain that the movement will get enough oil at this reduced speed. When the Fargo theatre ran a new print of a silent film shot in the are around 1920, we had to modify the PR 35/70 to do it. We found an old drillpress motor and stuck a pully on the inching wheel end of the motor. We then screwed a chunk of wood to the bottom of the projector motors cradle and put a belt on. we also provided a switch to switch between the two motors. at the slower speed of 18-19 frames per second, the movement got bairly any oil. luckily the film was only 12 minutes long. to reduce flicker, the bulb was defocused, and it worked great.

Josh

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William Hooper
Phenomenal Film Handler

Posts: 1879
From: Mobile, AL USA
Registered: Jun 99

posted 07-16-2001 01:43 AM

Be aware that "Silent Speed" varied from 16 fps for the early Griffith Biographs to 24 or more fps for some later silents.

David Pierce has information about silent film speeds at http://www.cinemaweb.com/silentfilm/bookshelf/#March1998

Make sure that you've got a pot on the motor control, not a multiposition switch.

Believe it or not, for a lot of the late silents, especially comedies, 24 fps will be correct. SMPE came up with the standard of 24 fps for sound speed by doing a survey of the speeds that most houses were running their films at - yep, 24.

But those Griffith Biographs & other early silents will sho nuff look wrong at that speed.

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Richard Fowler
Film God

Posts: 2392
From: Ft. Lauderdale, FL, USA
Registered: Jun 2001

posted 07-16-2001 07:12 AM

On better invertor speed controllers you can have two or multi speed preset and a variable pot. Silent speeds would vary and many important movies would also include a music score for the local musicians to play and "feet per minute" or frame speed that the projector should operate....there where speedometer attachments available from the projector manufacturers. Ten years ago I did several showings of a silent feature with a 30 piece musical group. The conductor who have toured the world with the print had me run the print at 20 frames per second for a general speed and several rehearsed speed changes within the performance....during the rehearsal is timing was so impeccable, that by watching the screen, he had me ramp up the speed and told me via headset when it was at 20fps...it was.

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001

posted 07-16-2001 08:01 AM

Although I've never personally had to do this to a Vic 5, some of my colleagues have.
On Westrex / Century machines we normally use a three phase motor and a digital programable inverter by Fenner. One can program a number of frequencies (therefore running speeds) and select them via a rotary switch on the pedestal. Should you wish to alter any pre-set it's simply a matter of tapping the relevant information into the inverter keypad. You also set things like ramp up speed, nominal overload current etc.

We normally fit three blade shutter and the lens centring issue can be dealt with by using a eccentrically machined lens sleeve. Or in the case of a single lens Century, by swinging the lens holder across by the relevant amount. Some old machines have the lens holder on film centre line, and you use a 'sound' sleeve to shift it into image centre line. In that case we use a standard lens sleeve, as the machine already provides the correct alignment for silent.

Something that's occurred to me about the Vic 5: What about the watt-governor that operates those irritatingly flimsy micro-switches? Depending on your automation / ACOP / whatever, you may find that the machine isn't running fast enough to operate those switches, so the equipment may shut down, or not allow the change-over to open. I've had first hand experience of that on a Vic 5 that's motor had suffered a heart attack and wasn't running at the right speed.

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Richard Fowler
Film God

Posts: 2392
From: Ft. Lauderdale, FL, USA
Registered: Jun 2001

posted 07-16-2001 10:12 AM

On a V-5 the governor/microswitch set-up usually kicks in at 12 frames per second so it is not a big problem.....in our situations, since we where running manually, the douser/fireshutter was generally locked up with the lock pin button at the top of the douser slot........
Richard Fowler
TVP-Theatre & Video Products Inc. www.tvpmiami.com

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Leo Enticknap
Film God

Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000

posted 07-19-2001 02:35 AM

If the V5 in question has a turret, you don't even need eccentrically mounted lens sleeves - it's possible to offset the lens for the optical centre of the 'full gate' frame using the adjustment screws.

I've run silents on V5s a fair bit (at speeds as low as 16fps) and have never had a problem with the governor switches. The light loss from the three-blade shutter, IMHO, is a much bigger problem. Bear in mind that tinted and toned prints absorb even more light than black-and-white ones. Assuming that your lamp output is speced to 16ft-l with a two-blade shutter, I reckon (though I've never had a meter to actually check this) with a three-bladed shutter at 16 with a tinted print, it could go as low as 9-10. So if this setup is going to run silents regularly, I'd suggest installing a lamp of sufficient brightness to give 16ft-l with a three-bladed shutter, and leaving it (the shutter) installed permanently, regardless of the running speed.

Incidentally, an excellent article on silent film projection speeds by Kevin Brownlow can be found in 'Sight & Sound', vol. 49, no. 3 (Summer 1980), pp. 164-167.

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John Pytlak
Film God

Posts: 9987
From: Rochester, NY 14650-1922
Registered: Jan 2000

posted 07-19-2001 07:24 AM

Leo said: "The light loss from the three-blade shutter, IMHO, is a much bigger problem. Bear in mind that tinted and
toned prints absorb even more light than black-and-white ones. Assuming that your lamp output is speced to
16ft-l with a two-blade shutter, I reckon (though I've never had a meter to actually check this) with a
three-bladed shutter at 16 with a tinted print, it could go as low as 9-10. So if this setup is going to run silents
regularly, I'd suggest installing a lamp of sufficient brightness to give 16ft-l with a three-bladed shutter."

Assuming the same image size, you will typically need twice the lamp power if you replace a two-blade shutter with a three-blade shutter. IMHO, shutter flicker is intolerable for a two-blade shutter at less than 20 fps. At 24fps, shutter flicker is imperceptable with a three-blade shutter, even at very high screen luminance.

But since you will be usually be using the full frame for silents, you should have more light available than a "cropped" format like 1.85:1 flat, where much of the light is lost at the aperture plate.

------------------
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

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Les Daniels
Film Handler

Posts: 11
From: Peachtree City, GA, USA
Registered: Jul 2001

posted 07-20-2001 12:58 AM

test

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Leo Enticknap
Film God

Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000

posted 07-23-2001 02:59 AM

I'd say from experience that as a general rule, you need to go up by one size of lamp. A couple of years ago I helped convert a university theatre to three-blade for a season of silents. They were all mainly European and 1920s and so needed the lower end of the speed range. Some of the black-and-white prints looked just about alright by increasing the power on the existing (1.6) bulb right to the upper limit of Osram's specified operating range, but for the tinted ones forget it. We put 2k bulbs in (which the rectifiers were capable of powering) and the difference was amazing. We had to reduce the current virtually to the bottom of the operating range when the two-blade went back on just to avoid washing out detail in the picture with too much light.

I agree that 20fps is the most usual cut-off point below which a three-blade shutter is essential, though it depends a little bit on the individual shutter design. Some are designed with tiny blades that have no leeway either side in order to maximise the available light (needless to say, these are also a pig to time, even when being used in two-blade configuration at 24). Watching silents on the DP-70s at the old Museum of the Moving Image cinema in London was excruciating, because they flickered like made even as fast as 21-22. Sitting through 'Napoleon' in there is the only experience I can think of which is guaranteed to give you a headache but which does not involve alcohol!

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