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Author Topic: Digital Projection-The Early Years Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 04-27-2015 11:01 AM                        from Motography, February 27, 1915 Ok, not quite digital, but on the right track  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 04-27-2015 01:42 PM                        Seems to me that the lack of a shutter would cause this design to fail. The incandescent lamps would not be able to dim/illuminate at a fast enough rate to work the same as a shutter, or to allow the proper lighting of each color.  |  IP: Logged Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 04-27-2015 02:31 PM                        Lee de Forest had the same problem with optical sound recording - the changes in intensity of the filament just weren't quick enough in response to the input signal - and basically hit a brick wall until Case came along with the AEO-light. The ironic thing is that with LEDs, this arrangement could probably now be made to work.  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 04-27-2015 06:49 PM                     In browsing through a number of old cinema-tech magazines & patents, it seems that for a many years, beginning in the late 1900's, engineers were searching for a way to build a 'shutterless' or 'continuous motion' projector. Many different designs were tried using various combinations of moving mirrors, prisms & lenses, with varying degrees of success. All of them suffered from extreme mechanical complexity,and loss of light. The only practical shutterless machine I'm aware of was the German Mechau. Strobe lights didn't come along till the early 30's. Experiments using strobes as a light source were tried, but strobes, especially the early ones, just didn't have the light output or 'recovery time' to put out a picture anything more than a couple of feet wide. I believe there was at least one shutterless telecine projector made either in the late 50's or early 60's that used a strobe (I think it was a GE 'synchrolight') but someone here probably knows more about that than I do. I do recall seeing a 'retired' one once at an old TV station some years back.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 04-27-2015 07:10 PM                        You are correct, Jim. The GE used a Simplex base. Also don't forget the Norelco, based on the FP-20.  |  IP: Logged Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 04-27-2015 07:14 PM                        There was also the "video Steenbeck", which consisted of a Steenbeck flatbed viewing/editing table with a CRT TV camera mounted in place of the rear-projection screen, with the camera's scanning being synced to the rotation of the prism somehow. The tapes they made were not bad, and it was the only telecine arrangement I know of that was available in the '70s and '80s that didn't cost megabucks but which also allowed transfers at frame rates other than 25 and 29.97. The main drawback was that contrast/gamma/color adjustment wasn't possible on an individual shot basis and so they were only any use for making quick-and-dirty reference viewing copies of film reels: its output was not of an acceptable quality for broadcast.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 04-27-2015 08:51 PM                     Philips built the SPP800 puls lamps for shutter free projection with the FP20S. And they had the puls light FP2 already back in the 30s. Yes, it is certainly easier now to do that with LEDs... - Carsten  |  IP: Logged Emiel De Jong Film Handler Posts: 48 From: Geldrop The Netherlands Registered: Mar 2007 posted 04-28-2015 01:50 AM                     Small correction there: the FP2 had a continuously burning high-pressure mercury lamp, and a shutter...  |  IP: Logged Jack Theakston Master Film Handler Posts: 411 From: New York, USA Registered: Sep 2007 posted 04-30-2015 03:58 PM                     quote: Leo Enticknap There was also the "video Steenbeck", which consisted of a Steenbeck flatbed viewing/editing table with a CRT TV camera mounted in place of the rear-projection screen, with the camera's scanning being synced to the rotation of the prism somehow. There was, in fact, a broadcast-acceptable version of this that was used at the BBC in the '80s called the Polygon. It's what Kevin Brownlow utilized for his documentaries "Hollywood" and "Unknown Chaplin."  |  IP: Logged Jeff Taylor Jedi Master Film Handler Posts: 601 From: Chatham, NJ/East Hampton, NY Registered: Apr 2000 posted 04-30-2015 04:21 PM                     I've seen articles on a shutterless 16mm JAN the military came up with years ago using an outboard-mounted xenon configuration. That thing must have chewed up a lamp's electrodes firing 24xps!  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 05-02-2015 05:16 PM                     Wouldn't one want the strobe to flash 48 p/sec to eliminate visible pulsing if no shutter was used?  |  IP: Logged

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