From: Tony Conrad (email suppressed)
Date: Sun Sep 19 2010 - 08:36:40 PDT
The simplest idea is to find out where the loop will be drawn tight, and have it
pull over a spool or roller at that point---a spool or roller connected in any
mechanical way to a 10Amp microswitch that turns the fast projector off for a moment.
This system will develop an interesting rhythm of its own, depending on the
elasticity of the mechanical elements.
On Sun 09/19/10 5:07 AM , "email suppressed
> There are two ways of doing this: electrical or mechanical. Either you
> use a common drive shaft, as was used for Dan Graham's Body Press
> film, or you have a crystal controlled voltage supply that locks both
> projectors to the same voltage. Such a system existed for three Elf
> projectors. The Arts Council of England had some and William Raban
> made a three projector time-lapse film, Thames Barrier (1977), using
> it. There's also an English filmmaker called Elizabeth McAlpine who
> has made some Super 8 films with six or so projectors that are
> mechanically connected via a series of chain drives.
> Nicky Hamlyn.
> On 18 Sep 2010, at 22:45, Steve Polta wrote:
> This issue has been discussed here before and as far as I know
> nothing very conclusive has come from it, i.e. no real solution has
> ever really materialized.
> Quite a while ago I was interested in this and tried it out. I was
> using Super-8, for the record. The problem is obviously that your
> projector will not run at exactly the same speed, the result being
> that, if the second projector is faster, the slack distance between
> gets shorter and shorter until the film snaps; if the first projector
> is faster, the slack builds up until you have a pile of film between
> the projectors. The trick is indeed to use projectors with rheostats
> (i.e. speed control knobs). This is part of the reason I was using
> Super-8: the Elmo projectors I possess have such knobs, which subtly
> increase the speed in the range of 1-2 fps. My biggest problem was
> confusing the projectors—i.e. turning one up when it should have
> gone down, etc.—but this seems easy to correct with practice.
> Ultimately I just abandoned this work so I have nothing to show for
> it. I think it could be potentially very interesting so I encourage
> others to pursue this. I can't say I've seen such knobs on portable
> 16mm projectors (but they may exist) but modification is always a
> possibility. As precedence, I've heard of a Sharits work which may
> have done this; also some early Luis Recorder pieces ran the same
> film through the same projector twice (looped over itself) and were
> very interesting.
> Good luck!
> Steve Polta
> --- On FRI, 9/17/10, D DAWSON __ wrote:
> From: D Dawson
> Subject: Re: [Frameworks] need help with dual 16mm projection
> To: "Experimental Film Discussion List"
> Date: Friday, September 17, 2010, 3:14 PM
> Depending on which projectors you are using, there may be a
> rheostat in one that will let you slightly adjust the FPS up or
> down... You can adjust and set this while they are running and it
> would help you tweak the slack if they were running slightly
> differently from one another.
> On 9/17/10 5:09 PM, "jeanne LIOTTA" wrote:
> On Fri, Sep 17, 2010 at 5:56 PM, mariah garnett wrote:
> I am trying to rig up an installation involving one 16mm film loop
> that runs through two projectors simultaneously. Does anyone have any
> advice on how to synch the 2 projectors so that the slack remains
> constant on both sides? I think I either need to rig up a slave motor
> or slave one projector to the other.
> Any advice?
> www.decodawson.com 
> -----Inline Attachment Follows-----
> FrameWorks mailing list
> email suppressed
> http://mailman-mail5.webfaction.com/listinfo/frameworks 
> FrameWorks mailing list
>  http://www.decodawson.com
>  http://mailman-mail5.webfaction.com/listinfo/frameworks
FrameWorks mailing list