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Author Topic: Pulse lamps........ Pete Evans Film Handler Posts: 11 From: Church Stretton, Shropshire, UK Registered: Aug 2003 posted 10-13-2003 05:03 PM                     In the early 70's when I was working at the NFT I was asked to help out at the nearby Queen Elizabeth Hall, which ran occasional films, on this occasion I had to run "Metropolis". The QEH was equiped with Philips DP70's with Pulse lamps, I was wondering whether anyone is still using these, I know that the Classic Piccadilly was also using them at the same time, but I wasn't that impressed and haven't come across any since.  |  IP: Logged Erick Akers Arse Kicker Posts: 201 From: Dallas, TX, USA Registered: May 2001 posted 10-13-2003 05:18 PM                     What are pulse lamps? I've never herd of them.  |  IP: Logged Hugh McCullough Expert Film Handler Posts: 147 From: Old Coulsdon, Surrey, UK Registered: Jan 2003 posted 10-13-2003 05:53 PM                        Pulse lamps were a Philips invention, and I remember using them at the ABC Croydon when we were testing out the, then, new FP20 projectors in the late 1960s. The projector was not fitted with a flicker shutter, instead the lamp flickered on and off, being on when the film was stationary in the gate, and off when the film was moving to the next frame. The idea may have seemed good, but did not work as the lamps life span was not very long, and the constant on-off-on cycle weakened the filament. They were also not very bright, at least not on our 135ft throw. After about 18 months we installed a flicker shutter, and went back to our Peerless carbon arcs. The last time I saw one of these lamps in use was on a Philips slide projector sometime in the midd 1970s.  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 10-13-2003 05:58 PM                    A filament? How could one possibly have a filament flashing at the necessary rate? I could see doing this sort of thing with either a strobe or some sort of pulsed arc but I don't see how it would work with a filament.  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 10-13-2003 06:01 PM                     At one time Philips made projectors which, rather than a continuous light source with a shutter to cut of the light during the pull down used a light source which gave pulses of light. The lamps were much smaller than xenons, and I think they may have been water cooled. I think they were some sort of mercury lamp. I've never seen a set-up using them, but I have seen pictures. I seem to remember that Bernard Tonks had experience of them.  |  IP: Logged Hugh McCullough Expert Film Handler Posts: 147 From: Old Coulsdon, Surrey, UK Registered: Jan 2003 posted 10-13-2003 06:12 PM                        Ok. Maybe the lamps did not use filaments, but thats what the engineers called them. They were much smaller than a xenon being only about 6ins long by about a half inch in width. I do not know if they were filled with any type of gas. They were not watercooled. Both the machines and the lamps were prototypes that we were testing.  |  IP: Logged Pete Evans Film Handler Posts: 11 From: Church Stretton, Shropshire, UK Registered: Aug 2003 posted 10-13-2003 06:22 PM                     I think you are right Stephen, I seem to recall they were water cooled, and if I remember correctly they were installed in pairs so that when one failed (as they did often) the other would drop into place, not altogether satifactory. As others have said the flicker shutter was removed, and the lamps flashed on and off. As I only worked on them for one day about thirty years ago, I can't remember much more, getting old you know!  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 10-13-2003 06:31 PM                     How widely used were these things? The first time I heard of them was at college in about 1974, where one of the lecturers happened to mention them. He had used them somewhere, I don't know where, but wasn't very impressed, for the same reasons you gave, Hugh, short life and low light output, also poor colour. He said they were replaced by carbon arcs. Since then I have heard of them several more times, but have never heard very good reports of them. The two projection lecturers were Ted Church and Harry Court; did you know either of them? Hugh wrote: quote: They were not watercooled. But Pete wrote: quote: I seem to recall they were water cooled Hugh also said that his lamps were prototypes; maybe the water cooled ones were a later development, to increase the available light output. Pete, I'm quite surprised that these lamps were still in use in the '70s, maybe as the QEH only ran film on an occasional basis they didn't think it was worth replacing them with something better. I would be very surprised indeed if any were still in use today. Philips, and later Kinoton were always very innovative, with such things as long run film handling, automation systems, single projector systems etc, and later, of course, platters. Philips are also a very major producer of discharge lamps of various types, so it is not surprising that they would have developed these. They also made a remarkable projector, with two mechanisms, one above the other, and four 2000 foot spoolboxes. Two projectors in the space of one.  |  IP: Logged Per Hauberg Jedi Master Film Handler Posts: 883 From: Malling, Denmark Registered: Jul 2000 posted 10-13-2003 06:43 PM                        The pulse lamps were, if I am not all wrong, presented together with the first FP20's at the 1956 Photokina exhibit in Cologne, Germany, as Philips' go for automation. Two FP20 projectors with pulse lights and 6000 feet reels automatic change-over was the future small and medium cinema. At the very same exhibition the DP70 was showing "The Miracle of Todd-AO". The pulse lamps were water-cooled, and due to the short lifetime of the bulbs, a spare bulb was mounted with the one in use, changing automatically to the new one, when the first burned out. Black-out, yes - but the change was quite fast and the lamphouse just "cute". The Philips trade paper "The Elagraph" had an article with pictures from the occasion. Maybe Thomas Hauerslev has got this in his archives to share. p.  |  IP: Logged Hugh McCullough Expert Film Handler Posts: 147 From: Old Coulsdon, Surrey, UK Registered: Jan 2003 posted 10-13-2003 06:50 PM                        I seem to remember that the FP20 projector weas advertised, at least in the UK, as the first shutterless projector, due to them using the Pulse lamp.  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 10-13-2003 07:02 PM                     It wouldn't surprise me if they did claim that, but there were shutterless projectors going back at least as far as the '20s.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-13-2003 07:16 PM                     The lamms made by Phillips were actually a pulsed Xenon lamp. Each lamp was in a water jacket and also there were two of them in a turrett assembly that allowed you to rotate to a fresh lamp of the one being used failed. Unfortunately they had a short life and as a result interest died out early on. I suspect that this technology could easily be perfected today though. If anyone knows of one of these machines as being available for purchase please contact me at work. Mark @ CLACO 801-355-1250 or cinerama84106@yahoo.com  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 10-13-2003 07:23 PM                     Since I probably ran the last pulse light around this was the scope The lamp was a capiliar mercury lamp with to small electrodes and an ignition filament on the envelope They ran in a quartz tube that water was pumped through and there were 2 of them on a rotating drum so when one failed the other could be droped in They synced to the projector via magnet on the intermitent flywheel on some and others had a opto through a sloted disk The pulsator was a tyrotron device with a rotating commutator The light output was poor and the colour rendition made the early Marc300 look like a futura 2 in comparison they were very bluey green I ran a pair of them for years in the late 70's on the back of a pair of FP16's  |  IP: Logged Larry Shaw Expert Film Handler Posts: 238 From: Boston, MA, USA Registered: Mar 2000 posted 10-13-2003 09:33 PM                        We have one of these systems in our inventory. Quite a few were in use in Canada until we were no longer able to get the bulbs. It may not have been the finest light, but once again I'd suggest if compared with what else was going on with image illumination technology in the 50's it was very advanced thinking.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 10-13-2003 09:37 PM                     The other problem with them was that there was always a small amount of dual travel gosting both up and down at the same time from the glow of the ignition wire  |  IP: Logged

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