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Author Topic: Flickering on the picture Gronw Roberts Film Handler Posts: 60 From: Y Felinheli, Gwynedd, Wales Registered: Oct 2015 posted 09-06-2016 10:06 AM                     We got a new Ushio DXL-40SN2 lamp in our NEC NC2000C projector a couple of months ago and has been working fine until recently (the lamp has around 650 hours on it). When a still image is on screen (snack adverts etc) you can see the picture flicker a bit, sort of like the effect of candle light. I've watched the light come out of the projector lense and you can see it flicker. It's not really noticable on moving pictures but something is definitely going on. Any ideas? Thanks.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 09-06-2016 11:44 AM                     There are quite a few of those lamps running in NC-2000's around here, mostly for 3-Dee. And I have had almost zero issues with them. What is the percentage of current in Flat & Scope mode, 3-D Modes?? You never want to run a lamp really high, so be sure that's at a reasonable level. The flicker is likely caused by arc wandering. First be sure your exhaust system is performing adequately. 1000 CFM or more at least. If that's up to snuff then try rotating the lamp and see if it settles down. While in there rotating it examine the electrodes to see if there is any pitting or buildup on them. Some times from rotation of the lamp you will find a happy point where the arc doesn't wander around and you'll make it to the number of hours. Otherwise you can pull it and send it in for warranty claim. This will take some time after which you'll get an answer back as to if the lamp was bad or is ok. Mark  |  IP: Logged Gronw Roberts Film Handler Posts: 60 From: Y Felinheli, Gwynedd, Wales Registered: Oct 2015 posted 09-06-2016 12:53 PM                     Thanks Mark. Is the % current the figure under the hours on the display? If so the Scope film running at the moment says 132%. Where do I find the readings for the exhaust system? We dont have a tube taking the hot air out, it just vents into the room. I contacted the installers and they suggested testing the lamp alignement, I was going to try that tomorrow.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 09-06-2016 02:34 PM                     Whoa! The percentage on the display IS the percentage of lamp current. You can see in this picture the lamp hours used is above the percentage of current readout. So if yours is reading 132% then you are way-way over the top end rating of this lamp. In fact I am surprised the firmware will allow you to run it up that high. Honestly, I never tried to see how high it can go. So, first be sure that you have the correct lamp selected and entered in Lamp & Lamp Setup in DCC. Then I'd be turning that current down to the low 80% range to where it SHOULD BE. Its also remotely possible your Xenon supply is bad and has gone to full output on you. Making sure the lamp adjusts correctly will answer that question. Be sure to "SAVE" your lamp settings after you adjust them or they will go right back where they are now. I am assuming you are venting straight out the top of the NC-2000 with no aux blower on it. Also, exhausting that heat into the room is asking for more trouble with rising temps. a 4kw puts out quite a few BTU of heat. IDK the exact amount of CFM the NC-2000 provides on it's own, but it's no where near enough for a 2kw lamp in a closed in room, let alone a 4kw lamp. If the ambient air vs. the exhaust temp gets too warm the projector will sense this and shut down the lamp. Also, if you do't have enough light at the 80% level with the lamp you are operating now then you need to switch to the 650 hour DXL that has sooper dooper high light output. A picture of your system would also help see how its installed... Mark  |  IP: Logged Gronw Roberts Film Handler Posts: 60 From: Y Felinheli, Gwynedd, Wales Registered: Oct 2015 posted 09-06-2016 03:24 PM                     I mentioned the % to our installer and he didn't say anything! That's rather worrying. I'll take some pictures for you tomorrow, I'm showing a film at the moment so probably shouldn't be setting off a flash!  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 09-06-2016 07:23 PM                     Just to solve my own curiosity I remoted into a projector thats running a DXL-40SNL and the highest on percentage it would go is 100%. If I tried to take it any higher I get a returned "It Failed In The Adjustment Of The Lamp" error. However, the top end capability of the projector as you can see IS 138 amps. So the maximum setting is definitely software limited on this projector provided you select the correct lamp. So lets be sure we are on the same page here with amps as displayed in DCC and percent of amps as indicated on the NC-2000 side panel display. DCC displays both of those by the way. Mark  |  IP: Logged Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 09-06-2016 07:28 PM                        Exactly, and I find that as the bulb gets older, "it failed in the adjustment of the lamp" happens at lower and lower percentages. For the 3kW bulbs we use in our 3240, they are warrantied to 1,200, but after around 700 hours you can only crank them up to about 90%, which just gets us 14ft-L on 'scope. So for that reason, we have to replace the bulbs after around 900. The only explanation I can think of for the NEC software letting Gronw crank up his bulb to 123% without "it failed" is that the software thinks that a lower rating of bulb is in there than is actually the case, e.g. a 30SN. If Gronw's bulb has done 650 hours and really has been overrun by 23% relative to its maximum designed amps for all of them, then no wonder it's flickering: essentially, it's buggered.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 09-06-2016 07:45 PM                     So Mark, you are using a 1920 PCF file? On a series 2? Why. I don't know if the 40SN will allow "overdrive" but if it does, it could explain it. He may also be reading the ampere value rather than percentage.  |  IP: Logged Gronw Roberts Film Handler Posts: 60 From: Y Felinheli, Gwynedd, Wales Registered: Oct 2015 posted 09-07-2016 12:39 PM                     Here's the pictures and screengrabs. The lamp should be installed correctly, it was put in when the installers came to teach us how to change the lamp. They checked everything, I'm a bit puzzled.  |  IP: Logged Leo Enticknap Film God Posts: 7474 From: Loma Linda, CA Registered: Jul 2000 posted 09-07-2016 01:54 PM                        I'm a bit puzzled, too. 95.8 amps is nowhere near 132% of the bulb's capacity. The correct bulb type has been entered into the software, so the 132% isn't being caused by DCC thinking that you've got a smaller bulb installed than you actually have (which is what I suspected earlier). 2,630 watts is 65.75% of 4kW, and if anything a bit on the low side (I've heard it said that 70-80% of amp capacity is the ideal for a digital projector bulb to run at). As you can see from the information tab, you're good to go up to 138 amps on that model of bulb. I'm wondering if the flicker might disappear if you crank it up to 3kW-ish. If you're getting 14ft-l of peak white with that power, you might like to consider going down to a 3kW bulb at your next change: the burn cost per warranty hour is significantly less (cost less to buy, and warranty to 1,200 hours rather than 1,000).  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 09-07-2016 09:58 PM                     I agree Leo, it is weird. I remoted into two locations with NC-2000's this morning and tried purposely to over power the lamp, and at both locations I could not go over 100% power. If I tried it said "Failed In The Adjustment Of The Lamp". Unless the DX-2 lamp does allow over drive (which still doesn't jive with the percentage-current reading) then something here doesn't seem quite right. Bad lamp, wrong lamp selected, or bad Xenon rectifier?? Mismatched DCC and Service Pack during Firmware updates can and does cause havoc too. Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 09-08-2016 02:20 AM                     You all missed it. This was not a factory setting of the lamp. This was a user creation. Note the "nominal" wattage was 2KW. That is why the percetage is reading high. Also note the high value is 4.5KW. One way to avoid all of that is to use the factory settings (the low entry numbers in the list. Even better is to use the "Cert Code". In each Ushio box is a slip of paper that has the Cert Code (long number with hyphens between the number strings). When putting in a new lamp, use the cert code bot OMIT the hyphens and the projector will select the correct lamp.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 09-08-2016 12:11 PM                     I rarely get to change lamps, generally only install them at time of projector installation, or if the customer asks me to do it while on a service call. IN most of those cases you are just re-selecting the same lamp again. I never use the cert code myself, just the lamp number on the setup list and I;ve never had any issues. Hyphens or not, there was a time when the Cert Codes did not work up until a certain service pack. And why someone wold create a "user lamp setup" is beyond me. That would very likely void the lamp warranty on any claim when Ushio looks at the logs. You set the projector for the wrong lamp and they are gonna send you that lamp right back. Mark  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 09-08-2016 05:46 PM                     The cert code isn't compulsory. However, by using it, nobody can deny you anything since you are using factory settings and the serial number will be tracked by it. Personally, I do find the Cert Code thing a bit of an extra step that nobody else has seen fit to offer. But they all do things differently. But yes, if a factory setting exists, then USE IT.  |  IP: Logged Manny Montes Master Film Handler Posts: 270 From: United States Registered: Feb 2010 posted 09-08-2016 08:37 PM                     Just tried cranking a 4k lamp that low for fun and it immediately started flickering, I'd try using the factory lamp settings as said above (never tried the cert code but will from now on though) instead of whatever user settings you have. It may fix the flicker when you're driving the lamp with more than 65% of what its rated for.  |  IP: Logged

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