Film-Tech Forum ARCHIVE: Anyone else see a 15K do this @ 500 hrs?

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Posted by Stewart Anderson (Member # 1809) on 04-26-2004, 06:37 PM:

This is a Ushio 15K that dimmed very suddenly at about 540 hours [Roll Eyes]

... Anyone seen this happen before or know why [Confused]

Posted by Jon Miller (Member # 163) on 04-26-2004, 07:11 PM:

Looks like it suffered a gas leak from seal failure. The blackness is from the electrodes burning up from lack of xenon pressure and the resulting air infiltration. I experienced that with a 2K over a decade ago; the lamp turned a marble-ish blue and black color. Better to go "pfft" than "blam!"

Edit: this is the lamp...

[ 04-26-2004, 08:25 PM: Message edited by: Jon Miller ]

Posted by Brian Michael Weidemann (Member # 2243) on 04-26-2004, 07:53 PM:

I think I've seen that before in a PerkinElmer 15K, dimmed and blackened, utterly useless. We had one once that blew some seal somewhere and filled with water (a miniature aquarium with no fish!). And then there was the one explosion that happened at less than 100 hours (that was a fun clean-up!) ... all three of these were PerkinElmer lamps, as I recall.

Never had one problem with an Ushio, though! (Knocking on the proverbial wood.)

Posted by Phil Hill (Member # 371) on 04-26-2004, 10:07 PM:

Yeah, definitely a gas leak/seal problem.

I also have always had great performance and "luck" with Ushio 15k & 20k lamps. Wouldn't give you a plugged nickle for Duratest. Had many spring water leaks into the bulb and then blow up...ususally taking the liquid-cooled refector with it.

>>> Phil

Posted by Paul Mayer (Member # 355) on 04-26-2004, 10:17 PM:

Looks like I've had the opposite experience to Phil's. Duratest 15Ks never gave us a problem at the Caesars Palace Omnimax. Had one blow up on me during my time there--about 30 minutes after a bulb change and IMAX service. Nice slushy clean up job but fortunately it didn't take out our reflector or cold mirrors.

Posted by Mark Gulbrandsen (Member # 72) on 04-26-2004, 10:30 PM:

Stewart,
These failures sometimes do happen with any lamp but are VERY frequent in the Perkin Elmer club. Hopefully your boss in charge has not resorted to buying from Perkin Elmer. Using their lamps a sure guarantee to more down time and less profits(no joke!). I'd stick with Ushio lamps for your operation.... you had been getting 1200 hours easily out of them and thats pretty darn good for a 15K lamp. You will see occasional failures like this once in a blue moon.
Mark

Posted by Stewart Anderson (Member # 1809) on 04-26-2004, 10:32 PM:

Makes me wonder how much time it would have taken this lamp to blow-up [Eek!]

...

Posted by Mark Gulbrandsen (Member # 72) on 04-26-2004, 10:48 PM:

A lamp that looses a seal generally does not blow up because all of its internal pressure has escaped very rapidly. I suppose that if conditions of gs pressure and seal wekining are just right that it might but I can't ever remember a lamp that has lost a seal and then blown up.

Mark

Posted by Gordon McLeod (Member # 33) on 04-28-2004, 09:23 AM:

Mark the original post says it was a Ushio that failed and that is rare
Also never had any problems with the durotest 15K lamps
The ushio offers a bit more light but I find it has a hot spot that doesn't defocus as well also the water pressure must be a lot higher

Posted by Richard Fowler (Member # 893) on 04-28-2004, 09:28 AM:

Perkin Elmer bulbs are no more. the division was sold last summer. The new owner is ASP with the bulbs made in China.

Posted by Mark Gulbrandsen (Member # 72) on 04-28-2004, 10:02 AM:

"The ushio offers a bit more light but I find it has a hot spot that doesn't defocus as well also the water pressure must be a lot higher"

Gord,
Have done setups of that system with the USL light meter getting 28fl plus or minus 3 fl at the edges and corners(3D system). Thats pretty darn good IMHO and thats with the lamp running at 12kw. I would suggest that your mirror and or optics are at fault as far as the hot spot go, perhaps just not functioning together too well. Ths CDC system has optics of much newer design than many of the old IMAX systems. Also from what I've seen of the SLC IMAX so far the CDC optics are also much much sharper corner to corner.

So far no problems anyplace that I am aware of with running the USHIO at the reccomended water pressure levels. All CDC machines and most Iwerks 15/70 installs all run USHIO lamps. If the water circulation system is properly designed in the first place that is nothing to worry about.

Mark

Posted by Dennis J. Losco (Member # 1374) on 04-28-2004, 12:56 PM:

Just in case some you do not know, Superior Quartz Products, Inc. purchased all of the assets from the defunct xenon division of Durotest in 2000. We revamped all of the equipment replacing vacuum pumps etc. Through production new quality check points have been put into place, along with overall improvements to the lamp. Average life is 1200 hours and we have less than a 1% return rate.

Stewart - Regarding the lamps that failed no need to worry about an explosion with this one. When a lamp turns blue and black it means that the lamps has gone to air while hot. There should be no pressure inside of this lamp.

Posted by Gordon McLeod (Member # 33) on 04-28-2004, 08:52 PM:

Mark we never had a hot spot with the DUroTest or superior quartz lamps just the USHIO and another 1570 had two ushios that the electrodes location was incorrect

Posted by Floyd Justin Newton (Member # 1316) on 04-29-2004, 06:54 PM:

It's been my understanding that 500 hours is the 'life limit' on
a 15KW xenon lamp.

fjn
Local 295 Ret. [Smile]

Posted by Dominique Replogle (Member # 2387) on 04-29-2004, 07:00 PM:

Floyd, you will be fine quite a bit longer than that. We typically go to about 1500 hrs before changing over and have been fine.

Posted by Floyd Justin Newton (Member # 1316) on 04-29-2004, 07:08 PM:

OK [uhoh]

fjn
Local 294 Ret.

Posted by Brian Michael Weidemann (Member # 2243) on 04-29-2004, 07:21 PM:

In my experience with our 15K Ushios, the warrantee runs out at 1000 hours or 250 strikes, whichever comes first. And for no reason at all are they to exceed 1200 hours. This has been a good working model, as we change them out RIGHT at 1000 hours.

Posted by Dominique Replogle (Member # 2387) on 04-29-2004, 08:57 PM:

I will pass that on to the museum director. Thanks Brian.

Posted by Robert Stawiarski (Member # 1842) on 04-29-2004, 09:07 PM:

Dominique: That information is also contained (almost verbatim) in the IMAX manual. You can e-mail or call Ushio (ask for Bob Fujihara) or IMAX directly for something more "official" to give to your theatre director. We change them out every 1000 hours as well. I know of theatres that run 1200 hours or more consistently, but it is not worth the potential risk of a lamp degassing in the middle of the day -- or worse -- a lamp explosion out of warranty.

Posted by Mark Gulbrandsen (Member # 72) on 04-29-2004, 09:20 PM:

Guys,
They are only running the 15K's at 12KW and going to 1200 hours in leiu of running at the top end, which is not needed anyway, has been most sucessful in all of the CDC and Iwerks installations. No explosions that I know of anyplace. This museum is also on a tight budget that they have to follow. If they have a lamp de-gas in the middle of a days run they will switch to running a 2D print of which there is usually one or two around.

Mark

Posted by Adam Martin (Member # 641) on 04-29-2004, 11:56 PM:

The blue color is from the tungsten electrodes reacting with the influx of oxygen to create a tungsten odide residue on the quartz envelope. The oxide may also be yellowish in color.

Posted by Paul Mayer (Member # 355) on 04-30-2004, 12:42 AM:

At Caesars the Duratest 15K's were warranted and pro-rated at 1,000 hours. That's the interval we used for changing out the lamps.

Posted by Carl Martin (Member # 1146) on 04-30-2004, 06:04 AM:

quote:
the warrantee runs out at 1000 hours or 250 strikes, whichever comes first. ... we change them out RIGHT at 1000 hours.

so if you haven't accumulated 250 strikes, that means you're doing 4+ hours per strike. is the bulb left on between shows? i'm surprised you can do that with a 15k. not that i know too much about imax... just curious.

carl

Posted by Darren Briggs (Member # 1071) on 04-30-2004, 08:09 AM:

I had a few problems with Osram short 2k lamps recently, both had broken seals, you could see parts of the glass seal in the envelope. The lamp was also blue.
Superior quartz seem to have re-designed there short 2K lamps and now last as long as they should do! Had a few instability problmes with the old design. Ligh5t going very flickery after 1500 hours.

Darren

Posted by Dominique Replogle (Member # 2387) on 04-30-2004, 11:23 AM:

We run our projectors from ten in the morning to about ten fifteen in the evening six days a week. We do not turn the lamps off between shows because we only run 15/70 alternating from 3D to 2D each show. At times in the slow season we might not sell a show and just leave the lamps on. Assuming that Carl's question was directed toward me, that is what we do. Do you guys recommend we turn the right eye lamp off for the 2D shows and when we do not sell a show? Our time between shows back to back all day runs around fifteen minutes.

Posted by Robert Stawiarski (Member # 1842) on 04-30-2004, 11:42 AM:

The general rule is that if a lamp is not going to be used for two hours or more, then turn it off and restrike it later. If you are running a 2D show and have a 3D show an hour later, leave both lamps on for the 2D show. Of course, only certain 3D systems can do this. IMAX, for instance, has a split-dowser system on some of their GTs that allows both lamps to be on for a 2D show, but many GTs have the single large dowser and only one lamp can be on for 2D.

It sounds like you have a similar split-dowser setup, and since you said you alternate from 3D/2D for most shows, I would leave both lamps on.

Posted by Brian Michael Weidemann (Member # 2243) on 04-30-2004, 02:07 PM:

We run the split-dowser GT system. Our current schedule is:

11:00am Sacred Planet 2D
12:30pm NASCAR 3D
1:50pm Sacred Planet 2D
3:10pm Sacred Planet 2D
4:40pm NASCAR 3D
7:00pm NASCAR 3D
8:20pm NASCAR 3D
9:40pm NASCAR 3D

We strike the one lamp in the morning, the other for the 12:30pm, then we shut off the lamps and re-ignite just the one for the block of 2D's, then the second one again and leave them on for the whole night, including the hour+ break before 7:00pm. (Then we alternate which deck we run the 2D on every few weeks.) I think this is the most efficient use, keeping both hours and strikes low.

A couple months after Matrix Revolutions opened, we were running that movie one show at 11:30am and another at 6:00pm (with a 35mm show in between), so of course every show got its own lamp strike and 2.5 hours ... those lamps lasted eight months before we had to change them out, because of schedules like this!

Posted by Dominique Replogle (Member # 2387) on 04-30-2004, 02:20 PM:

Brian,

we are looking at bringing in Sacred Planet? Good Film?

Posted by Gordon McLeod (Member # 33) on 04-30-2004, 10:23 PM:

We run our lamps 1200Hrs and they are left lit all day (unless there is a split morning and evening type schedule
Between shows they are on standbye of 275amps

Posted by Brian Michael Weidemann (Member # 2243) on 05-01-2004, 05:16 AM:

Hey Dominique. I believe you saw my review of the film in the reviews section. To summarize: pretty looking film, kinda slow, overall good and traditional IMAX grade documentary stuff.

As for the topic at hand, is there any evidence that standby mode extends lamp life? It was my impression that it was mainly for cooling reasons that the lamps go "to half" when the dowsers are closed (even though there wouldn't be any benefit anyway to have them at full when not on-screen).

Posted by Steve Guttag (Member # 268) on 06-19-2004, 06:30 AM:

Darren,

There are at least two popular forms of 2K short lamps. There is the standard 2000HS that is in the 2500HS package. It is more popular and is offered by several lamp maufacturers (the 3000HS also uses that package).

Then there is the bastard 2000HS in the 1600HS package. This one has the threaded pin on the cathode. OSRAM, SQP, and Ushio make this one, as far as I can tell. Note Christie doesn't offer it under a CXL marking...only Ushio with a UXL (I think it is UXL-21SCB or some such thing).

Anyway...I was just working a with a pair of Osram's version and one was okay but the other had this pulsating flicker that was quite annoying.

Steve

[edited to show actual Ushio xenon lamp number]

[ 06-20-2004, 12:21 AM: Message edited by: Steve Guttag ]

Posted by Gordon McLeod (Member # 33) on 06-19-2004, 04:31 PM:

The dowser in some lamphouses would have an issue with the lamp left at full for extended periods and the dowser closed