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Author Topic: Barco DP2K Lamp not striking Antti Nayha Master Film Handler Posts: 268 From: Helsinki, Finland Registered: Oct 2008 posted 05-20-2014 09:57 AM                     Here's an earlier thread about this. quote: Paul Maxon I have one that is starting to miss strikes now, but is stable once lit. But it is the 3D house so the lamp power is changed when the format is changed, so that could have something to do with it. I've had the dreaded Barco strike problem with several Ushio lamps, and this was in a house where we used to run 2D flat at minimum power and 3D at maximum power. I think it's pretty much accepted knowledge that going back and forth between the extremes is not exactly good for any xenon lamp... And as Pete suggested in the previous thread, particularly running at minimum power may cause strike failures in the long run. Even when you're only using CLO to even out the difference between 2D flat and 2d scope on a common height screen, the power difference is quite substantial - let alone between 2D and 3D. Since I've found no way to restrict the CLO minimum and maximum power to something more conservative than Barco's presets, I've started to rely less on CLO and more on manual power settings. For example, the aforementioned house uses an Ushio DXL-30BAF/L, which Barco's CLO happily runs at 1800-3000 W. I've now disabled CLO and set it up manually to always run 2D flat at 2000 W and 2D scope at 2800 W. Both 3D formats are also now being run at 2800 W. The projectionists then focus the bulb z-axis manually to get maximum light output for 3D shows, and defocus it down to 14-16 fL for 2D. (The light uniformity is pretty good despite defocusing, although of course it would be nicer to have another lamphouse for 3D...) This way, the lamp is never fed either extreme minimum or extreme maximum power. And although I lose about 0.3-0.4 fL in 3D (measured through glasses) because I run the lamp at 2800 instead of full 3000 watts, I guess this is evened out towards the end of bulb life, since avoiding maximum power makes it lose its brightness a bit slower. So far so good, although it's a bit early to tell. Would be interesting to know if any of you guys with dozens of screens have tried something similar to combat strike problems.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 05-21-2014 11:33 PM                     quote: Antti Nayha The projectionists then focus the bulb z-axis manually to get maximum light output for 3D shows, and defocus it down to 14-16 fL for 2D. (The light uniformity is pretty good despite defocusing, although of course it would be nicer to have another lamphouse for 3D...) I like this phrase if held true if projectionists are still in hire. But, with locations run by "suits" and floor staff, can one see any member of the above personnel perform these above techniques on a regular basis? Thus, for this "new system of operation" we have nowdays, what would be the simplest "KISS" method to use to have the most effective usage with these BARCOS (since I have 15 of them and no booths to speak of.. ?) EDIT: On this same topic of bulbs in general with these BARCOS: We all know that a xenon bulb works the best when in operation at 80% of it's rated wattage, then gradually work upwards when age gets on bulbs. Now, in the CLO mode, the light sensor file has been set at a certain foot lamberts so the bulb ramps up automatically when age is gaining on the bulb itself. Yet, with some FL readings, that the bulb is operating way below the 80% run (e.g. a DXL-30BAF/L is only operating just about 2200 watts with a 14fl setting in the sensor file) making me wonder if I'm actually killing the bulbs running this low of wattage where I wish I was using 20BAF/L bulbs, but have too big of screens for this smaller bulb. ..or, am I just worrying about nothing and these bulbs can handle this lower wattage and still be effective throughout its warranty life. -thx Monte  |  IP: Logged Antti Nayha Master Film Handler Posts: 268 From: Helsinki, Finland Registered: Oct 2008 posted 05-22-2014 02:35 AM                     I suppose that starting at 70–75% power and gradually raising by CLO should be OK for a 3000 W lamp. See this Manice article and Christie's "Best Practices" document. If you have common-height screens, you're still faced with the problem of evening out the light levels between flat and scope without huge current changes. Cue Steve G with his recommendation to use automated anamorphic lenses to deal with that. For 3D, I suppose the best low-maintenance option is to dedicate some of your auditoriums completely to 3D if programming allows that. Or use a dual-projector system, which has other advantages. Then there's always RealD XL, which helps you even out your 2D/3D light levels due to its superior 3D light efficiency - it's not without its problems, though.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 05-22-2014 02:56 AM                     Thx for this added info from these two sites. Makes sense even though I've seen some BARCO units never ramp up the amperage when bulbs get the age on them, but actually decrease amperage to where, in the service window to monitor the bulb run, the power scale is below the minimum wattage range. This is when I'll take it out of CLO and go standard to manually ramp up some more power get some more light out of the bulb.  |  IP: Logged Antti Nayha Master Film Handler Posts: 268 From: Helsinki, Finland Registered: Oct 2008 posted 05-22-2014 03:05 AM                     Sounds like incorrectly calibrated or non-calibrated LSC files to me. I've never heard of that kind of problem with a correctly set up Barco CLO - not saying it's not possible though.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 05-23-2014 12:27 AM                     After reading David's and Steve's post on adding multiple ignition cues, I tried it tonight prior to my late showings of X-Men:DOFP. In the SPL build and before the lens cue, which contains the "lamp on" command, I added a 10sec Black MOS clip prior to this and added a "Lamp On" cue with a one second delay at the beginning of this clip to cure this hard strike issue with my 32B unit. Works like a charm.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-23-2014 12:54 AM                     Monte, Note, you can put the multiple lamp strike cue right in the projector macro too. If you have an automation that will do macros...again, one can add multiple lamp strike cues in there.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 05-23-2014 01:02 AM                     Well Steve, Barco service said non-pleasant things to us about putting the lamp on command more than once in a projector macro...even though their very own training school recommended it. If you're going to put it more than once in a projector macro, at least add a delay in there before the second one.  |  IP: Logged Marcel Birgelen Film God Posts: 3357 From: Maastricht, Limburg, Netherlands Registered: Feb 2012 posted 05-23-2014 03:07 AM                     quote: Brad Miller Well Steve, Barco service said non-pleasant things to us about putting the lamp on command more than once in a projector macro...even though their very own training school recommended it. Putting a few seconds between strikes sounds reasonable in all aspects, but... Besides support just being support and bitching about some procedures only they know, what could be the potential problem with that? Are they afraid you damage either the lamp or igniter circuit in doing so? That might be the case if you put like 10 or 15 or so of those cues in a sequence, which would be pretty useless anyway. But it's not like it will try to strike again when the previous strike was successful...  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-23-2014 07:59 AM                     Barco support actually recommended it to me. But yes, with a delay...I forgot to mention that but it should seem obvious that it be multiple attempts, not just some idiot hitting the elevator call button successively. -Steve  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 06-22-2014 02:09 AM                     Back on topic on hard strikes: UPDATE - I did make contact via email (support.digitalcinema.usa@barco.com) with BARCO on this hard strike issue. Reply back was that they sent an .pdf attachment pertaining to the arc stabilizer magnet located in the lower half of the module. That stabilizer magnet was known in copper rod, non-rotating carbon arc lamphouses to push the flame upwards from the gap for an even arc by increasing flux lines in the negative rod. For if the magnet wasn't there, the flame would just "ball" in in the arc itself. Plus, the alignment was to keep the flame in the middle and not tilted off-center of the rod layout. Same with xenon bulbs - flame must be pushed upward for proper operation and if magnet reversed, the flame will just gather around the electrodes and cause irregular burn. BARCO will send the user a bar magnet with one end painted to recognize the North end of the stick, and the South end of the stabilizer magnet is to be on the left side facing the user for correct placement. One moves the red end of the test magnet to the left end to determine attraction or repel of the bar magnet. One can prob do this with a compass to check magnet polarity placement - red end of the needle swings towards the magnet end for proper field attraction. Some info to share - thx, Monte  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 06-22-2014 03:08 PM                     Are you saying Barco are sending magnets to users?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-22-2014 05:54 PM                     It is news for me. Normally, they would have an Info-T on such a thing. Then again, they should have an Info-T on the B series lens mount shakes too since there is an improved mount now.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 06-22-2014 06:29 PM                     They did. InfoT1160. I'll email it to you.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-22-2014 07:03 PM                     How did you get it? I don't see it on "My Barco" with the rest of the InfoTs.  |  IP: Logged

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