Film-Tech Forum ARCHIVE: When to swap a bulb?

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Posted by Andrew Thomas (Member # 7000) on 01-30-2015, 01:18 PM:

I have 4 Christie series 2 projectors (1 CP4220, and 3 Solaria Ones).

We get 14+ FTL on screen with new bulbs at the lowest output setting, and still get 14 FTL at about 80%. The bulbs are past their rated hours (at about 3000 on CDXL30, and 3800 on the CDXL-16Ms) but I haven't even had any issue with any of the lamps failing to strike (except at about 1500 hours on on the Solaria Ones after a bad software update) and as I said, the image is still plenty bright.

So do you do changes at specific hours, light levels, when errors start?

Thanks.

Posted by Gavin Lewarne (Member # 5397) on 01-30-2015, 02:37 PM:

I change lamps no later than 100-hours-to-warranty, which for us happens to always be every year.

I would never, ever, take any lamp in a digital projector past its warranty hours. Doing so, is frankly, stupid.

Not sure what the exact lamps you have are but those hours are way beyond any warranties hours for any lamps I know and I would change them PRONTO

Posted by Marco Giustini (Member # 4544) on 01-30-2015, 05:48 PM:

It's a matter of math.
If a lamp exploded in a Christie then you have to replace the whole reflector - and you lose shows.

I heard a reflector is about 4 grand. Plus engineer and loss of revenue.

Is that worth the savings on the lamps? Your call.

Posted by Stephan Shelley (Member # 8587) on 01-30-2015, 07:40 PM:

In addition to the two parts of the reflector the UV filter will be shattered as well. If you are very unlucky on the 4220 you could nick the integrater rod or the cold mirror on the solaria ones. none of this stuff is cheap.

Posted by Andrew Thomas (Member # 7000) on 01-30-2015, 08:01 PM:

None of this has been a cost question, I just have no idea and we are still on the original bulbs that were installed when we opened 13 months ago.

So you guys typically change at around the warranty hours? Is there a particular reason for that as opposed to the average hours listed on the Christie bulb pages?

Posted by Stephan Shelley (Member # 8587) on 01-30-2015, 08:10 PM:

If the bulb explodes during the warranty hours the bulb manufacture covers the cost of the damage as well as the bulb.

Posted by Buck Wilson (Member # 5885) on 01-30-2015, 08:11 PM:

If a bulb blows within warranted hours, the bulb manufacturer will cover the cost of any damage done to the projector.

Posted by Justin Hamaker (Member # 2165) on 01-30-2015, 08:14 PM:

With regard to the bulb its self, the question is whether you are in warranty on you projector and whether the bulb is still performing as expected.

If your projector is still in warranty, then you should never run a bulb past the rated life. This can void warranties. If the projector is beyond warranty, then it's a cost/benefit decision as long as the bulb output is still bright and stable. In this case it just comes down to whether the savings from running a bulb past warranty is worth the potential cost of replacing parts in your projector, and the associated down time.

If a bulb is lasting you a full year, that means you are running a fairly limited schedule. My theatre runs a minimum schedule during the school year, but the rated life on a bulb still only gets us about six months. The cost of a bulb once a year is probably far less than any projected equipment replacement costs. Plus the savings of squeezing an extra 6 months from a bulb is minimal.

Posted by Andrew Thomas (Member # 7000) on 01-30-2015, 08:59 PM:

Thanks for the wise council! We will be swapping all the bulbs in the next week anyway, but we will move to a replacement policy at the warranty hours. Again, cost doesn't make much difference to me...as has been mentioned, the difference is pretty minimal anyway.

Posted by Ram Melegrito (Member # 8652) on 01-31-2015, 01:04 AM:

Our supplier is giving us a warranty for our bulbs of 1,000 hours. We have about ten hours worth of shows everyday; we replace the bulbs every three months.

Is the 1,000-hour limit correct? There are only two suppliers for all cinema projection equipment here in the Philippines, and one is exclusive to one of the major local chains. I feel as if they're setting a 1,000 limit so that we order more often, given the lack of choices for suppliers.

Posted by Leo Enticknap (Member # 534) on 01-31-2015, 01:30 AM:

quote: Ram Melegrito
Is the 1,000-hour limit correct?

Depends on the manufacturer and how big the bulb is. Across our two sites we use three types of bulb in total: a 3kW which the manufacturer warranties to 1,200 hours; a 6kW to 600 and a 7kW to 500.

Before I started to work with digital projectors, the general operating practice in pretty much every theater I worked in was to try to run bulbs to at least double the warrantied hours. For example, at one place we ran 1.6kW bulbs in most of the projectors. The warranties were for 1,500 hours, but with quarter-turn rotations every 500 hours and regular checks to ensure that airflow wasn't degraded (e.g. as the result of clogged intakes or failed fans), it was very unusual not to get 3,000 hours (ish) out of them before they started to flicker. It was when they started to flicker and the flicker couldn't be eliminated by rotating them that we tended to replace them.

No-one who supervised me, who I worked with or later, who I supervised believed the risk of explosion to be significant. Techs with decades of experience assured me that the spontaneous explosion of a xenon bulb while burning simply hadn't happened since the 1970s (except for a once-in-a-blue-moon freak event), thanks to improvements in the manufacturing process. Therefore, running the bulbs way past warranty hours was considered a risk worth taking, and we took it. I have only ever witnessed one bulb blow up while lit, and that was as the result of a very damp atmosphere and something like 90% humidity air being sucked into the lamphouse (the theater in question was in its first day of reopening after a huge flood).

In the digital world, however, comments such as those above represent what I've heard from everyone I've talked to: don't run your bulbs one minute over warranty; the risk isn't worth it. Is this just because the consequences of one exploding are so much greater (the reflector is a lot more expensive to replace in a digital lamphouse and other components, in closer proximity to the bulb than is typically the case in a film projector lamphouse, are also at risk), or are the xenon bulbs designed for digital projection more prone to spontaneous explosion in use when excessively worn than those designed for film lamphouses?

Posted by Carsten Kurz (Member # 5396) on 01-31-2015, 05:14 AM:

The risc of a bulb blowing increases with lamp type and wattage, and operating current. Also, digital bulbs have a different design (smaller etendue for digital projectors), increasing the risc even more. Then the cost for mirror+parts replacement in a digital projector is much higher than for film lamphouses.
We probably all know those places running 1.6kW lamps in their 35mm lamp houses for thousands of hours. These would simply 'never' blow, only become dimmer and dimmer.

- Carsten

Posted by Marco Giustini (Member # 4544) on 01-31-2015, 05:33 AM:

Carsten,

In my experience most of those 35mm had metal reflector which had the advantage of not shattering if the lamp exploded.
I've seen so many badly damaged metal reflectors in old 35mm. The customer thought it was ok. The light output would pay the consequences of course but that was apparently ok for the average cinema.

Posted by Dave Macaulay (Member # 813) on 01-31-2015, 10:17 AM:

Generally, each xenon lamp type from each manufacturer has an hour limit for the replacement warranty, pro-rated for lamp replacement: at 50% life, a failed lamp will be replaced for 50% of the new lamp price. A few lamps actually do have a 1000h warranty, many do not. Smaller wattage tends to be more, higher wattage less. Ushio has extended hour lamps that have over 2000h warranties.
Lamps also have a service life warranty, higher hours than the replacement warranty: if a lamp explodes within it, the ensuing lamphouse damage repair cost is paid by the lamp manufacturer. Past that and, yes, you have to pay for replacement glass mirrors and probably the UV plate: these are not cheap!
Some large chains, maybe some large distributors, buy lamps without warranty - considerably cheaper but they have to pay for early-failure lamp replacement and explosion damage repairs.

I would check on the manufacturers website for the official warranty conditions for your specific lamp.
Something is fishy if your supplier is giving a 1000h warranty on all lamps.

Posted by Leo Enticknap (Member # 534) on 01-31-2015, 12:08 PM:

Thanks Carsten - that was the explanation I suspected and am grateful to have confirmed. Digital bulbs = different design increasing the risk of explosion, plus higher cost of repairing collateral damage.

Yet another example of how the transition to digital has shifted the up-front cost of technical presentation from the studio/distributor to the exhibitor. Assuming that you don't perpetually take, and get away with, the risk of running your bulbs significantly past replacement warranty, then the cost per hour in bulb time for DCP presentation is significantly higher than it is with film (all the other relevant factors being equal).

This is because, as you say, in the film days, you could more or less take the warranty length and double it for what the realistic bulb life actually was, and pretty much everywhere did; but the risk/benefit analysis for a digital bulb comes out against doing that, and so a digital house has to budget more per hour of screen time for xenon bulbs.

Posted by Stephan Shelley (Member # 8587) on 01-31-2015, 01:50 PM:

For another example of warranty life. We have 1.6 kw with a 3000 hour warranty, 2 kw with 2400 hours, and a high performance 3 kw with only 1000 hours. A theatre I service uses a 1.4 kw at 3000 hours, 1.8 kw at 1750 hours and a 3 kw at 1500 hours. All of the above 100 % replacement of the bulb and explosion damage for the full hours. Most manufactures have abandoned the prorated stuff. None of these have the service warranty. But I have seen service warranties on bulbs for Barco. The above are for Christie and NEC.

Posted by Monte L Fullmer (Member # 2797) on 01-31-2015, 05:26 PM:

I'm running USHIO 65BA2's in my two 32B Barco units and I've only got 500 warranty hours with these 6500 watt bulbs. My wattage run on these bulbs are only 4700 watts due to the settings in the Lumen output.

I'm trying to get 60BA2/L lamps since these are long life bulbs that has extended the warranty to 800 hrs, with the slight percentage of light loss due to a slightly less wattage of lamp.

Thus, when the counter hits to pull, I pull pronto even if the bulb has no flicker, clear envelope and no hard strike.

Thing missing in this discussion is that full efficiency of any xenon lamp is within the first 300 hours of operation. As the lamp ages, so does the brilliance of the light itself making the image on the screen look so flat and dull looking even though there are no issues of hard strikes, flickering or seal ends going tarnish due to lack of cooling.

-Monte

Posted by Martin Murray (Member # 162) on 02-02-2015, 01:56 AM:

Monte, what are you doing with those good bulbs you are pulling? I would like to have them.

Posted by Marcel Birgelen (Member # 6801) on 02-02-2015, 03:32 AM:

quote: Leo Enticknap
In the digital world, however, comments such as those above represent what I've heard from everyone I've talked to: don't run your bulbs one minute over warranty; the risk isn't worth it. Is this just because the consequences of one exploding are so much greater (the reflector is a lot more expensive to replace in a digital lamphouse and other components, in closer proximity to the bulb than is typically the case in a film projector lamphouse, are also at risk), or are the xenon bulbs designed for digital projection more prone to spontaneous explosion in use when excessively worn than those designed for film lamphouses?

Besides the fact that the specific, compact and high power design makes them more prone to explosion, there's also some effective scaremongering amongst manufacturers, maintaining their lock-in scheme which isn't anything different from razor blades or ink cartridges. The big difference: Not only are the blades expensive, the razor is mighty expensive too. So, they do have an effective means of forcing you to change the blades, even if they would be good for a few weeks worth of shaves. Continuing to shave with worn blades, might irreparably damage your uber-expensive razor too.

Keep in mind that Christie for example, is a wholly owned subsidiary of Ushio. Christie essentially sells the expensive sockets to burn expensive lamps. Barco, another of those big four DCI projector players, is squarely in bed with OSRAM.

There's no real incentive in the current industry players to offer an exit out of the current cycle of rather short-lived Xenon bulbs. Yes, there's laser now, but considering the costs of such a system, you can burn a whole lot of bulbs before it starts paying itself back. So, none of those players will be interested in offering a bunch of lamps that offer a dramatically increased in life span at roughly the same costs.

The best hope for an improvement here are probably the Chinese, with their copycat Xenon bulbs. If they reach comparable quality levels of current de-facto standard bulbs and will offer the same or better warranty conditions as the big name manufacturers, this market might finally be moving in a direction more favorable for the exhibition industry.

quote: Andrew Thomas
None of this has been a cost question, I just have no idea and we are still on the original bulbs that were installed when we opened 13 months ago.

If you're on VPF, you might want to check your contracts as they usually require you to change those bulbs within the warranty timeframe. Failing to do so, can have severe consequences, especially if a damage does occur.

Posted by Steve Guttag (Member # 268) on 02-02-2015, 06:50 AM:

I disagree on the "lock-in" theory as well as the shot life claim.

Almost all of our Barco customers use Ushio and ditch the worthless "free" Osram either after that first lamp or on right on installation. Our customers use Ushio because they are simply the best lamp out there. They hold their light better than the others and get you more light per watt in most categories.

As for lamp life...in film, a 2KW lamp (nice middle of the road lamp size at neither extreme), we had a 2400-watt rated life that was pro-rated for the bulk of film's life. With digital, depending on projector manufacturer, that same size lamp is now a 3200-hour with 100% coverage...hardly a short life lamp. Oddly, if you swing down in the 1400-1600 watt range we went from the 1500-hour "Film" lamps to 3000-hour "digital" lamps.

With film lamps, the arc gaps were larger and tended to just run providing that the number of strikes were kept to a minimum and they were fed good power (low ripple and low in-rush). With digital, the arc gaps are much shorter (which is one way they get them more efficient...the ideal light source is a point-source). One characteristics of these super-short arcs is that once that gap opens up past a certain point...the lamp stability drops like a rock. It isn't unusual for a lamp to be stable one day and flckering bad the next. Combine that with the lack of shutter to "hide" the flicker, digital lamps tend to look "good" for less hours than film lamps...not so much because they are actually performing worse but because their performance isn't being masked, to a degree.

As for going over warranty...get out your spread sheets and do the math (the same with lasers). That is, how many reflectors can you "eat" versus the odds that a lamp will let-loose out of warranty. Which lamp manufacturer you choose will play into this because some are more prone to explode than others. What projector company you use also factors in. If you use Barco, and you do "allow" a percentage of lamp explosions, you can have a spare lamphouse on site already loaded with an aligned lamp in case a lamp does explode. But lets say you adopt a policy of warranty plus 25% or +50%...at what point do you find yourself with too high a potential of damaged equipment versus cost savings on the lamps? You also have to factor in customer satisfaction in there too...you WILL lose customers if your shows don't always run. But you would lose them if the lamp was in warranty too. With Ushio lamps, I think you'll have unacceptable light before you start to worry about explosions. We definitely have a customer that changes lamps on "demonstrated need" and they routinely get 50-100% extra life and they use a mixture of Ushio and Osram. They have yet to have to buy a reflector. They have had lamps that go off mid show though.

Posted by Marcel Birgelen (Member # 6801) on 02-02-2015, 08:39 AM:

quote: Steve Guttag
I disagree on the "lock-in" theory as well as the shot life claim.

I never claimed things were so much better for "film", yet again, they didn't exactly improve a whole lot and I'm giving some reasons for this. Also, there isn't a whole lot of choice out there. Its either Ushio, Osram and maybe Philips and if you're adventurous, some Chinese knock off.

I don't really agree on Osram being totally rubbish though, their small and mid-size lamps usually perform well up into the warranty period, although I agree that Ushio seems to be more stable in the whole run. But for some reason, nobody but Ushio really seems to get the high end bulbs right.

quote: Steve Guttag
Combine that with the lack of shutter to "hide" the flicker, digital lamps tend to look "good" for less hours than film lamps...not so much because they are actually performing worse but because their performance isn't being masked, to a degree.

On this I totally agree and it is part of the "problem" of digital. The absence of a shutter in the system increases the visibility of lamp flicker considerably, an unstable lamp will therefore be almost instantly noticed.

quote: Steve Guttag
As for going over warranty...get out your spread sheets and do the math (the same with lasers). That is, how many reflectors can you "eat" versus the odds that a lamp will let-loose out of warranty. Which lamp manufacturer you choose will play into this because some are more prone to explode than others.

I doubt there aren't many in the position to do this kind of math right, since there aren't really many trustworthy numbers to do the math with. It's also not like the manufacturers are so forthcoming with those statistics, as they could hurt their bottom line.

So, whenever you're pushing a policy of going over the warranty hours, you're really just guessing. The uncontained explosion of a Xenon bulb is quite rare nowadays, for any given big name manufacturer. But even with a considerable sample size, like your own customer base, it might be just guesstimating in the wild and not basing your decisions on any statistically profound basis.

I guess, in the end it's just better to be safe than sorry. For all operations running a normal, profitable, healthy business, swapping the bulbs on time and within warranty should therefore be the standard operating procedure.

The situation might change in the future and depending on your mode of operation. If you're running your operation on a bunch of refurbished projectors and you've got a whole bunch of spare parts lying around, you might be able to "afford" a busted lamp house or two. In this mode of operation, you could also save quite a few bucks with running your lamps to till they drop dead or flicker so much, it's more like going to the disco than to a movie theater...

Posted by Steve Guttag (Member # 268) on 02-02-2015, 10:18 AM:

In the USA...I haven't seen the lamp manufacturers change much in terms of who can supply what. Now, your brand of lamp may not show up on the "list" of approved lamps but nothing is stopping you from putting in your "favored" lamp and putting its information in. NEC merely reserves space for its "certified" lamps but leaves more than abundance of room to put in "your" lamp. Barco allows for one to make their own "custom" lamp type so again, you can put any lamp in if you know its parameters.

Christie has historically only recognized Christie lamps (look on the back of their film console/lamphouses...they always put the CXL number they wanted). But you could still put in that "HTP" lamp if you liked other brands.

As for Osram...complete junk and quite explosive...had them explode too many times in both digital and film lamps to ever trust them again. They also are the most difficult to owning up to their defective crap. If you like them...use them...but I wouldn't inflict that crap on people myself. That said, thus far, the NEC versions have performed better than the other versions for whatever reason.

As for the spread sheet...no you aren't going to get hard data from the lamp manufacturers...any hour beyond warranty is an "on your own" condition. Christie does list their "Average Life" which is typically a bit beyond their warranty life.

However, a chain or theatre could certainly experiment and start to run 25% over and see how the lamp is performing or merely change lamps at demonstrated need and keep track of hours versus lamp model and converge on what a good prediction of lamp life is. Once they have that they can factor in the savings in lamps versus potential risk to equipment and customer good-will (the toughest part of the equation).

Posted by Monte L Fullmer (Member # 2797) on 02-03-2015, 12:52 AM:

Martin: I sent you a PM on your inquiry - please read. thx-Monte

Posted by Martin Murray (Member # 162) on 02-03-2015, 02:46 AM:

I replied Monte thanks.

I usually run my 4500 w bulbs 2300 hrs average.
My 6k and 6.5k usually average 1400 hrs. I have pushed 16-1700 out of a few.
I know that I go against the grain but I'm getting close to the same hours that I used to get on 35mm projectors. I pull bulbs when there is noticeable light loss, flickering, or hard to strike. I've been running them this way for years probably have saved 60-70 k in bulb cost in that time. I own all of my equipment and I'm responsible if something goes wrong. I don't recommend anyone running their lamps as long as me unless the fully understand xenon lamps, the risk involved, and don't have any warranties or contracts that would be voided for running lamps past warranty.
This is my results, your mileage may vary.

Posted by Steve Guttag (Member # 268) on 02-03-2015, 06:25 AM:

And there you have it...even if Martin were to have a catastrophic failure, the money he saved over the time thus far could certainly buy the repair of many reflectors/UV filters or even integrating rods...heck, it could buy another projector...even at 4K resolution.

All is not cut and dried and it is a policy that each theatre owner has to come up with for themselves.

Posted by Marco Giustini (Member # 4544) on 02-03-2015, 11:28 AM:

quote: Martin Murray
My 6k and 6.5k usually average 1400 hrs. I have pushed 16-1700 out of a few.

I'm sure you have plenty of light at 1400 hours on a 6.5kW - flickering won't be a problem either.

Posted by Carsten Kurz (Member # 5396) on 02-03-2015, 05:29 PM:

The interesting question is: If Martin had experienced an explosion and a 4k bill on his first or second bulb - would he have proceeded with his scheme?

- Carsten

Posted by Andrew Thomas (Member # 7000) on 02-03-2015, 06:33 PM:

quote: Carsten Kurz
The interesting question is: If Martin had experienced an explosion and a 4k bill on his first or second bulb - would he have proceeded with his scheme?

From the limited time I've spent with Martin, probably [Razz]

Posted by Marcel Birgelen (Member # 6801) on 02-03-2015, 06:55 PM:

quote: Steve Guttag
In the USA...I haven't seen the lamp manufacturers change much in terms of who can supply what. Now, your brand of lamp may not show up on the "list" of approved lamps but nothing is stopping you from putting in your "favored" lamp and putting its information in. NEC merely reserves space for its "certified" lamps but leaves more than abundance of room to put in "your" lamp. Barco allows for one to make their own "custom" lamp type so again, you can put any lamp in if you know its parameters.

Next time I will try some wrapped up aluminum foil, shouldn't be so difficult to get the parameters right [Wink]

.

I highly doubt the lamps in the USA are any different from the lamps in Europe or the rest of the world. The market for those specialty lamps surely isn't large enough to justify producing them in multiple plants around the world.

quote: Steve Guttag
As for Osram...complete junk and quite explosive...had them explode too many times in both digital and film lamps to ever trust them again. They also are the most difficult to owning up to their defective crap. If you like them...use them...but I wouldn't inflict that crap on people myself. That said, thus far, the NEC versions have performed better than the other versions for whatever reason.

Maybe there's a difference after all, the US versions must come with some sort of nitroglycerin doped cathodes [Smile]

.

I have not experienced an exploded Osram bulb yet. As a result, I also have no experience in how well they treat warranty cases with equipment damage. In my opinion, Osram isn't as consistent as Ushio, but far better than Philips in general. Ushio also happens to be the most expensive option around here. But, what is it for you then? Ushio or Ushio?

quote: Carsten Kurz
The interesting question is: If Martin had experienced an explosion and a 4k bill on his first or second bulb - would he have proceeded with his scheme?

That's the whole problem right there. You're essentially playing a game which is potentially worse than Russian roulette, because you have absolutely no clue what the odds are. A few years down the road, once there will be a somewhat lively aftermarket for DCI gear, the situation might change, but unless you're running a major chain and do have the means to experiment, optimize and balance risk on a larger scale, I wouldn't want to expose my über-expensive gear to such odds.

Posted by Steve Guttag (Member # 268) on 02-03-2015, 08:08 PM:

Sort of... Ushio or Christie [Razz]

I think you misinterpreted my response to how the rules are in the USA versus other parts of the world. I don't ever presume that the rules remain the same (like our warranty hours here versus in another part of the world)...it is entirely possible that there are legal ramifications that are different in other parts and the fact we get 3200-hour 100% credit warranty on a particular lamp size may not be the same in another country.

As for Osram...you know my view point on them. If you read various comments here on Film-Tech...you'll find that I'm not alone with my distain for them and truly resent that they come in most of the Barco projectors (every once in a while you get an Ushio...particularly in the DP2K-10S).

Posted by Leo Enticknap (Member # 534) on 02-03-2015, 08:25 PM:

I have to confess to being a little surprised at Steve's consistently bad experience with Osram. I've never used their digital bulbs, but I spent around a decade using their film bulbs, and probably went through several dozen 1.6kW and 2kW units during that time. Apart from the one that exploded shortly after a flood in an extremely humid booth, none of them ever blew up and most lasted to double their warranty hours before starting to develop a flicker. Maybe the alternatives would have been even better, but that buying decision wasn't mine to make.

Posted by Monte L Fullmer (Member # 2797) on 02-04-2015, 03:01 AM:

I worked at another multiplex where we had 4 Barco 20C units and we were using OSRAM XBO4000DHP bulbs.

My only bad experience with these bulbs is that they were hard striking after 800 hours and one bulb took out a unit's SPG (igniter) due to multiple strikes.

After all of these issues with Osram, we finally swung over to USHIO and their DXL-40BAF bulbs and issues of hard strikes disappeared.

One of our sister location lost two reflectors - one in each module- due to Osrams letting go before warranty.

Posted by Steve Guttag (Member # 268) on 02-04-2015, 06:17 AM:

Leo...I've had Osrams blow up in the box in shipping (both film and digital)...I've had an Osram XBO-3000W/HTP arrive with its anode rolling around in the envelope yet not exploded (and they wanted us to file a claim with the shipper, not them). They suck and they have sucked for a long, long time.

Every lamp manufacturer has their good and bad batches. I'm not expecting 100% all of the time. But with Osram...35-years of personal experience with them have driven me to the conclusion that they are just an unreliable lamp with way too much hassle on warranty. If they work for you, more power to you.

Mind you, I've tried a great many lamp brands over the years...when I was with a chain, we would put lamps "head-to-head" in identical systems and tried to draw conclusions as to which performed the best...including down to the cost/hour. I've tried X-Cel (Marble), Conrad-Hanovia, Osram, Christie (Ushio), ORC (eventually now ASL), Superior Quartz, Goldberg (more explosive than any of the above) and Phillips (LTI). Christie/Ushio isn't just a little better...it is a LOT better than the alternatives.

I had a customer that only wanted Osram but was disappointed with the life with them, particularly in one of their consoles. They let me put a Christie in there and it made him a believer and has been on Christie/Ushio since.

Of the low-cost lamps, honestly, ASL has been the best we have used. There have been a few explosions (depends on the model lamp...they seem to do better with some than others or perhaps they had bad batches) but they are wonderful to deal with and don't fuss on warranty. Some of their lamps stand toe-to-toe with Christie/Ushio...the XM6000HS/G, for instance, puts out identical light to the CXL-60SC and lasts at least as long. The XM4202 is also a winner with a lot of light for a 4KW. I haven't played too much with their digital lamps though. They only have a couple of lamps on the Barco list and I don't think any on the NEC certified list (and Christie only recognizes their lamp, officially). Thus far, Ushio (Christie) have really just proven themselves to our customers as a hassle free lamp (about 99% of the time...there is that odd one that doesn't go the distance).

Posted by Leo Enticknap (Member # 534) on 02-04-2015, 10:47 AM:

Maybe the pattern we're starting to see is that Osram's smaller bulbs are OK (e.g. the 1.6es and 2s), but the bigger ones simply aren't as consistent or reliable as the competition? At my current workplace, we use Ushios in our two NEC digital projectors: 6kW in one, and in the other a 3kW for 2-D projection and we swap in a 7kW one for 3-D shows, plus whatever comes built into the cradles of our iS8-2K in our smallest screen. One pair of film projectors uses 6kW Christie bulbs and Osrams (4kW) are in the other. I'm not sure if these are a conscious choice, the only brand our supplier carries in those ratings and configurations or just the way things have always been done.

I have noticed that while the Ushios and Christies tend to make it to warranty hours and still look good, the Osrams quite often don't get that far before starting to flicker. As I say, I never had that problem with the much smaller Osrams I used in England in the '80s and '90s. But there again, I haven't been here long enough to be clear in my own mind whether this is a consistent, long-term pattern, and if it is, whether the bulbs are the only relevant factor.

Posted by Paavo Mardi (Member # 4962) on 02-04-2015, 12:53 PM:

I also have bad memories with Osram. First two Barco projectors we had came with Osram and both lamps failed before warranty hours. Last year 4 Barco 20C units were installed in my booth. Barco communicator showed that all lamps are Osram. But these lamps kept running and all passed warranty hours. I already thought that Osram is now worth to buy until I pulled the first lamp out - Ushio, Made in Japan.

Sorry for offtopic.

Posted by Steve Guttag (Member # 268) on 02-04-2015, 01:14 PM:

Sorry...Leo...the 2KW Osrams sucked too...Osram will just never touch a Ushio on either quality or longevity. Sure you'll find that odd one that may be atypically good/bad but if you are a betting person, only a fool would take the odds of Osram versus Ushio.

Posted by Monte L Fullmer (Member # 2797) on 02-04-2015, 07:29 PM:

Just something happened when Osram got mixed in with Sylvania and Osram just went downhill after the merger.

True: ORC/Perkin Elmer/ASL equals very bad medicine.

Had one new LTi that also had the anode that broke off rolling around in the envelope as well along with another new LTi with the quartz broken around the seal and the gas has leaked out.

Posted by Ron Curran (Member # 3631) on 02-06-2015, 12:57 AM:

We always replace bulbs at or close-to rated lifetime, then immediately order a new one to go into the cupboard. When it arrives, we dispose of the used one.
Last week we installed a new bulb which ran full Wattage but showed just 7.73 ft lumens for Scope. Never had a low-lumen bulb before. So we had to go through the whole instal number again with the newly-arrived bulb which is perfect.
The low-lumen bulb is physically fine so it will just have to play an absolute emergency role.

Posted by Carsten Kurz (Member # 5396) on 02-06-2015, 04:50 AM:

A nearby small 5plex uses all OSRAM, 3*6kW and 2*3/4kW. Never had issues. All Kinoton projectors. I asked them a few times wether they would consider USHIO, but they replied 'Why?' You can imagine, how many bulbs they run through with all these systems (all 6kW running Dolby 3D). The projectionist says they have no trouble getting to the warranty hours.

KINOTON in germany always promoted OSRAM bulbs, for what reason ever...
Maybe their lamphouses deal better with bulbs.

- Carsten

Posted by Steve Guttag (Member # 268) on 02-06-2015, 06:45 AM:

Osram is the lamp of Germany, isn't it? I could see it promoted on that reason alone. I normally like German cinema stuff (Kinoton, ya know)...but not for lamps and it isn't like I didn't give them their due. For me, the best always wins...It doesn't matter if it was Kinoton projectors or Christie/Ushio lamps.

Posted by Marcel Birgelen (Member # 6801) on 02-06-2015, 08:23 AM:

Maybe it's like with the French and their wine. They drink all the good stuff themselves and the rest of the world has to do with the inferior stuff that's leftover afterwards [Wink]

.

But well, yes. Osram is a household name around here and in general a well respected manufacturer of bulbs and lamps. Osram usually isn't the cheapest choice, but also not the most expensive. Ushio/Christie usually is the most expensive option, but that surely may also depend on your volumes and negotiation skills.

Posted by Carsten Kurz (Member # 5396) on 02-06-2015, 08:59 AM:

Cinema Technology Magazine published lab visits for all major Xenon manufacturers and you could see how different their manufacturing processes were and how delicate Xenon manufacturing still is. Quite interesting read.

Here's the one covering OSRAM:

OSRAM lab report

Here's Philips in LA:

Philips lab report

I can't find the one on Ushio right now.

OSRAM can't be as bad as Steve suggests - they would have left that market behind long ago - with the same replacement and burst coverage warranties like Ushio and Philips, no Xenon bulb manufacturer can deliver substantially bad quality.
The site I mentioned has piles of Osram only boxes in their booth, they run through 15-20 bulbs a year, it's an owner operated business, they would change to Ushio if they wouldn't be satisfied with OSRAM. They can't be the only lucky ones.

That said - if we'd operate Xenon machines, I would opt for Ushio, too, as they also offer a nice product variety.

Hmm, as a matter of fact, we do, as we have no choice ;-)

- Carsten

Posted by Steve Kraus (Member # 476) on 02-06-2015, 11:55 AM:

I had good luck with Osram film bulbs for 35mm at my screening room and ran them until there was arc wandering flicker. They were 1600W but run at the lower end of current range. One of the bulbs in place when I took over had something like 5000 hours on it and was running fine. I inherited a couple more pairs of Osram bulbs when I took over and later, given the lesser risk on a film lamphouse, even successfully put in some picked up cheap on eBay.

With digital I went with an NEC NC1200C and have been running a 2000W Osram film bulb (XBO 2000W/HS OFR). It'll soon be at 1900 hrs (over about 2.5 years) so time to replace. I have another Osram on the shelf ready to go in but discussion here makes me wonder if I should go buy an Ushio.

It does not seem like I would have much to gain from a digital bulb. We have too much light as it is and have the aperture in place to enable keeping the current up to levels good for the bulb. Greater hours might be nice but at my level of usage that's hardly a factor and if digital bulbs undergo the greatest change or risk of hard or non starts then maybe I should just stick to a film bulb. So the question would be whether to hope my luck with Osram holds out or maybe spring for a Ushio film bulb like a UXL-20SC.

Any difference in colorimetry if I change from what I've been using?

Posted by Brad Miller (Member # 2) on 02-06-2015, 12:08 PM:

I would throw the Osram in since you've already bought it and buy an Ushio as a spare. Just watch the Osram closely. I could see them fighting a warranty due to it's age, so I would not leave it on the shelf as a backup to the Ushio. It's usually quite the struggle to get Osram to make good on their warranty replacements.

Posted by Steve Guttag (Member # 268) on 02-06-2015, 12:14 PM:

Steve, Ushio makes 1200, 1500 as well as 2000-watt lamps for your projector. The smaller lamps come with a 3000-hour warranty (100%) too. Since they are more efficient, your electric bill should go down too.

If you already have the other lamp, and it has warranty in it...go ahead and use it (tough to throw away free money). Otherwise, I'd go with the smaller Ushios.

Posted by Steve Kraus (Member # 476) on 02-06-2015, 04:49 PM:

Thanks; that's what I'll do. And keep the old one with a hundred warranty hours left as the spare so there's not money sitting on the shelf. But for the future Ushios, would you agree to stick with the film bulbs?

Posted by Steve Guttag (Member # 268) on 02-06-2015, 05:14 PM:

Nah...I'd go to the smaller digital lamps. As I said, either the DXL-15SN or the DXL-12SN, depending on the size of screen you have. They are more efficient than "film" lamps (shorter arc), designed for the optics of your projector, have a longer warranty life and don't decay in light as fast as film lamps (typically at about 1/3 the rate).

Posted by System Notices (Member # 2357) on 05-08-2018, 10:17 AM:

It has been 1186 days since the last post.

Posted by Steve Kraus (Member # 476) on 05-08-2018, 10:17 AM:

I'm bringing up this thread because at long last I need to order my next bulb (only the third since going digital in Sept 2012---business is dead slow).

As stated, I've been running the Osram 2000W film bulbs. This is with the aperture / iris thing in place to cut output so that the bulb can run a sufficient current to keep it happy. We are common height so Scope needs the most light; we're running 95-98%. I'd have to look to see the actual current.

Given the low esteem Osram (Sylvania?) seems to have now I will go with Ushio. The question is whether a bulb like the DXL-15SN (1500W digital bulb), with aperture removed, will be adequate.

Projector is the NEC NC1200C. Scope picture is about 7.5 x 18'. The screen is a Hurley with very slight gain. I don't recognize the type but here is the tag:

I can always just get a UXL-20SC and just stay the course.

Using one unnamed vendor's prices the digital bulb @ 3000 hrs costs $.2375 per hour while film bulb @ 2400 hrs costs $.2295 per hour which is only trivially different.

There would be some savings on the electric bill but by my estimation, including demand charge dropping by .5kW, probably not more than a few dollars a month. So that's kind of a wash as well.

BTW, I pulled the first bulb at 1950 hrs because I thought the warrantied hours was 2000 and wanted a usable spare. It's not worth the effort but in theory I could put it back in and run it out to 2350 hrs. That's 90 dollars worth right there!

Posted by Steve Guttag (Member # 268) on 05-08-2018, 12:34 PM:

That is a Hurley SuperGlo. Depending on the day made and the dirt on it, between 1.5 and 1.8 gain.

Given that lamp warranties expire in 2-years, regardless of hours, that is probably what you'll be up against.

Posted by Carsten Kurz (Member # 5396) on 05-08-2018, 03:00 PM:

@Steve (Kraus): Where is that aperture/iris positioned?

It may do you good contrast-wise, as the 1200C is a 0.98" DLP and would benefit slightly from the increased contrast due to the iris in the light path. Not a game changer, but reduced electricity bill is just one side of that medal. And, as I remember you operate a screening room, a little bit of extra punch may be good.

That said, you may be okay WITH a smaller USHIO bulb AND the iris left in place. Because a digital bulb will be optimized for a smaller etendue light system, while the previous film lamp probably wasted more light than necessary in a 0.98" DLP.

- Carsten

Posted by Steve Guttag (Member # 268) on 05-08-2018, 07:59 PM:

Carsten, NEC includes the IRIS with the NC1200/NC2000 projectors. It goes right by the fold mirror. It is a single iris (aka "cats eye") as they don't make sets. Ironically, NEC is the least light efficient to begin with.

If you have access to the NEC NC2000 "Installation Manual", they call it the "Small Iris" and that section is not translated into languages other than English.

Posted by Steve Kraus (Member # 476) on 05-08-2018, 08:34 PM:

Screen is from 1994. Surprised it's not original (1985).

The aperture thing went in on the left side when facing the screen. Some of you know James Bond and he did this when setting color etc. He opened the left side, and had me hold some part of the cooling system while he put it in.

I guess there is no way to assure that a 1500W bulb will be sufficient based on the greater efficiency of the digital bulb and with the aperture removed until one tries it.

A third option would be a 2000W digital bulb at only a very slightly higher price. The aperture would stay in but one could experiment with it removed and see what current level is needed for proper brightness. (Probably too low for the bulb to be happy long term.) If the current level is within the proper range of the 1500W digital bulb, that would be useful information for the future.

Posted by Mark Gulbrandsen (Member # 72) on 05-08-2018, 09:13 PM:

Digital lamps are seemingly more critical of adjustment, so you may be able to defocus the 2kw lamp just slightly to compensate. Note that if you ever do actually update the projector your choice of lamps increases considerably in size and brands. There are now 1200 and 1500 watt Ushio DXL lamps available.

Ushio DXL Lamps

Both Osram and Ushio claim their 2kw digital lamps have a range of 1400 watts to 2000. Osram hasn't been the most reliable though. Supposedly they have gotten better.

Mark

Posted by Bob Ezra (Member # 841) on 05-08-2018, 10:46 PM:

"Given that lamp warranties expire in 2-years, regardless of hours"

is this true? news to me

I just changed a 3200 hr Ushio (it lasted 4 yrs.).With the backup
bulb I bought in 2014. Does this mean it is already out of warranty?

Posted by Steve Kraus (Member # 476) on 05-09-2018, 09:43 AM:

That's a further reason to favor the bulb with the shorter hours.

If one is going to run the bulb to the end of what would otherwise be warrantied hours, if not for the 2 year limit, better to replace at 2400 rather than 3000 as the "beyond warranty" operation would be less. And if one did replace the bulb regardless of hours just because it's 2 years old, the wastage would be less.

Between that and not knowing for sure if 1500W digital / no aperture will suffice I guess that decides things for me.

Posted by Mark Gulbrandsen (Member # 72) on 05-09-2018, 10:24 AM:

Running these lamps past warrenty is stupid unless you have an extra 4 grand laying aorund to buy a new mirror and heat filter. I don't have a single customer running lamps past rated warranty and lamps are an expense write for many of them anyway.

Mark

Posted by Mike Blakesley (Member # 26) on 05-09-2018, 12:12 PM:

quote: Bob Ezra was the last to post
Given that lamp warranties expire in 2-years, regardless of hours

Is this true?? Around here I change the bulb about once every year or maybe up to 15 months depending on how many shows we run. I do like to keep a spare bulb on hand.... but if they expire based on purchase date, what am I supposed to do...run without a spare and risk losing a couple nights of shows if a bulb goes out prematurely?

If this is true, it's a classic example of companies writing their policies based only on high quantity customers. Every purchaser should be able to depend on the warranty.

Posted by Steve Kraus (Member # 476) on 05-09-2018, 01:10 PM:

If it's purchase date not install date then my current bulb went out of warranty in November 2014! Low hour users may not have much choice but to run out of warranty lest their cost per hour quadruple.

Posted by Bob Ezra (Member # 841) on 05-09-2018, 03:18 PM:

I was quoting what Steve Guttag said in his post after the - It has been 1186 days since the last post- message

I called Ushio , and was told, whatever the warranty hrs are, that is how long the lamp and damage are covered.

sorry for needlessly stirring the pot

Posted by Steve Guttag (Member # 268) on 05-09-2018, 05:51 PM:

I'll look it it up but yes, there is a use-by date. Otherwise, one could be seeking a warranty claim many years past manufacture. I'm reasonably sure it is 2-years though it may be 3-years.

[EDIT] just got an update from one manufacturer, Ushio, and they do NOT have an official dead-date though if it is "really old" then there may be an issue but not for one that is just a few years. So, legally, they may have an issue denying warranty on a lamp based on age on the shelf since "really old" is a non-specific answer. This may vary by country too. I know that EV's lifetime warranty on their microphones was shown to be null and void after something like 20-years though.

Posted by James Westbrook (Member # 3690) on 05-10-2018, 02:22 PM:

I was told, back in the 35mm days, to look at the manufacture date stamp on the xenon bulb box and use the oldest bulbs first, similar to stock rotation at the concession stand.

Posted by Steve Kraus (Member # 476) on 05-11-2018, 10:08 PM:

Here is an experiment I suppose I could do. Pull the iris thing and crank the current down to that of a 1500W bulb. If I can make the proper brightness in Scope at that level, then a digital bulb's greater efficiency should do so easily. Hmmm.

Posted by Marcel Birgelen (Member # 6801) on 05-12-2018, 01:56 AM:

quote: Steve Guttag
[EDIT] just got an update from one manufacturer, Ushio, and they do NOT have an official dead-date though if it is "really old" then there may be an issue but not for one that is just a few years. So, legally, they may have an issue denying warranty on a lamp based on age on the shelf since "really old" is a non-specific answer. This may vary by country too. I know that EV's lifetime warranty on their microphones was shown to be null and void after something like 20-years though.

What's not clear though, is if they'll also honor the guarantee to pay for the potential repair costs of your equipment if one of their bulbs explodes prematurely and if the bulb was past the expiry date. Those costs can be potentially far higher than that of just a new bulb, even without the potential economic damages of lost shows that no warranty will cover.

Posted by Carsten Kurz (Member # 5396) on 05-12-2018, 06:46 AM:

@Steve Kraus: I'd take a shot at the 1500W Ushio digital bulb.

Is that '95-98%' your overall setting for the film lamp, your initial setting, or do you run it close to 100% now near the end of it's life? If you run that film lamp at 95-98% all the time, there'd be no reason to use the iris (lightwise).

Maybe actually look up the current.

If that screen really has a gain of near 1.8 - as a screening room, I'd replace it sooner or later with a lower gain screen - in that case, you may be better off with a 2kW digital bulb. But if you want to keep that screen for now, take the 1500. Ushio doesn't cheat on their performance parameters. The NEC1200 has a small 0.98" imager, so a digital lamp will really be much more efficient. As the 1500W lasts longer, you will also have less light drop over the same time span. I don't think you can loose there.

- Carsten

Posted by Steve Kraus (Member # 476) on 05-14-2018, 11:54 AM:

For Scope I'm presently at 82A. You may be right about pulling the iris. I bet I will end up in the middle of the range for 2K bulb current. But what is the lowest an older 2K film bulb can go without risking arc wandering flicker?

I do wish to replace the screen with either a micro-perf or perhaps a woven non perf screen but with the business very marginal right now there is no plan.

Posted by Carsten Kurz (Member # 5396) on 05-15-2018, 04:25 AM:

You should be fine down to 65-70%.

Again, I'd go with the 1500W Ushio and try to leave the Iris in place.

- Carsten

Posted by Mark Gulbrandsen (Member # 72) on 05-15-2018, 11:19 AM:

So much adoo about nothing... Sheesh! When to change the bulb.... [Roll Eyes]

Posted by Steve Kraus (Member # 476) on 05-15-2018, 02:32 PM:

Carsten, 1500W digital bulb and *keep* the iris?

Or did you mean the 2000W digital bulb w/iris? I was concerned that 1500W would not be enough even pulling the iris, whether increased efficiency of the digital bulb would be sufficient but you're convinced that it would even with the iris? Or was that a typo?

Posted by Carsten Kurz (Member # 5396) on 05-15-2018, 03:08 PM:

Yes, I'd try the Ushio 1500W bulb WITH the iris left in place. Do you have a screen brightness meter? Will you change the bulb and adjust yourself?

- Carsten

Posted by Steve Kraus (Member # 476) on 05-15-2018, 08:50 PM:

Yes, I would be changing the bulb and I have a Harkness Screen Checker to set brightness.

Posted by Mark Gulbrandsen (Member # 72) on 05-16-2018, 11:04 AM:

With the 1500 watt you likely won't make screen brightness after you reach 80% of the rated life. I'd be installing the 2KW with iris... you have 7100 out of the 1500 Lumens vs 9700 lumens out of the 2kw. Not all that much more output (2600 lumens) from the 2kw, but that should be enough to maintain screen brightness. One must also take into consideration that NEC projectors are not as light efficient as Christie or Barco. Hence, using the next larger lamp has always worked better for me over the full rated hours of the lamp.

Mark

Posted by Steve Guttag (Member # 268) on 05-16-2018, 06:23 PM:

Well, for starters, an NC2000C isn't able to output 9700 lumens on a good day, even with a digital lamp. Sure, NEC publishes that it will output 9700 but I defy anyone to measure one outputting that lumen level at the right color temp. With a new lamp, running 100% you might lick up around 9000 lumens, depending on the lens and the way the wind is blowing. It is probably in the mid to upper 8000s.

However, Steve indicated that he is using a "film" lamp (2000HS style with the supplied adapter) so you can knock 20% of the light off right there on the new lamp. And then factor in the accelerated lamp decay (lose another 20% after 100 hours). So I suspect that a DXL-15SN would output as much ore more light than a UXL-20SC (or equivalent) on day 1 and 300+ hours in will likely output more light as it will have a shallower decay.

Posted by Mark Gulbrandsen (Member # 72) on 05-16-2018, 07:27 PM:

He has an NC-1200 Steve, not an NC-2000. And those are the Ushio lamp specs, not the projector specs. Just thought I should let you know. I agree the UXL will have less fall off though. BUt it's also wasting lots of light since the reflector is mismatched to the lamp.

Mark

Posted by Steve Guttag (Member # 268) on 05-17-2018, 06:01 AM:

As far as NC1200 versus NC2000, same projector, different ballast so, as far as this discussion goes, zero difference.

As for the light, no it is absolutely NEC's numbers (I've asked Ushio about this because the numbers are absolutely not real-world). NEC has number inflation on their specs. Earlier NEC sheets only claimed 9300 lumen on the same lamp (DXL-20SN3) and yet magically jumped to 9700 without changing anything. When one specifies an NEC projector, you have to throw away about 10-20% from whatever they publish, that day.

https://www.nec-display.com/global/dlpcinema/lamp/certified-lp.html

In the link above, check it out, the Philips lamp allegedly gets 10,900 lumens. Yeah right!

Note, on the link above, they denote that the lamp-life is supplied by the manufacturer. They make no notes about the lumen output is supplied by them. I guess Osram didn't pay them off because their 2KW only goes to 9000 lumens.

On the bigger (1.2/1.38") projectors they state that brightness was measured with a set of lenses. Again, yeah right. So their 4K and 2K projectors put out the same light? And the light doesn't vary with lens focal length and lens model? Seems improbable.

Posted by Mark Gulbrandsen (Member # 72) on 05-17-2018, 07:23 PM:

Well, thats off this page at Ushio. Its also interesting that Ushio also makes the optical system for those projectors.

Posted by Monte L Fullmer (Member # 2797) on 05-17-2018, 07:29 PM:

Interesting that the bulbs set for the NEC units can muster more warranty hours than the bulbs made for the BARCO of the same wattage.

Posted by Steve Guttag (Member # 268) on 05-18-2018, 07:04 AM:

Yes Mark, it is off that page and those numbers were supplied by NEC.

Posted by Steve Kraus (Member # 476) on 05-18-2018, 07:57 AM:

So where are we at? Is everyone agreeing that the 1500W digital bulb (no iris) *may* not be sufficient over its full life? Then I might as well buy another 2000W film bulb (Ushio this time). The digital bulb has a longer life but costs more thus operating costs are essentially the same so what would it gain me?

Posted by Carsten Kurz (Member # 5396) on 05-18-2018, 11:21 AM:

In germany, we have Ushio representatives that actually come and visit your cinema with a bulb and install it to show you the benefits and convince you to switch brands. Don't know if Ushio offers the same service in the US.

- Carsten

Posted by Mark Gulbrandsen (Member # 72) on 05-18-2018, 01:49 PM:

quote: Carsten Kurz
In germany, we have Ushio representatives that actually come and visit your cinema with a bulb and install it to show you the benefits and convince you to switch brands. Don't know if Ushio offers the same service in the US.

In previous film years I have had both Osram and Ushio come out to investigate some strange recurring problem Osram did find back in the late 90's that Srong 3KW high reactance rectifiers had way too much inrush current. Other than the salesman or Factory Rep, today you would never see them.

quote: Steve Guttag
Yes Mark, it is off that page and those numbers were supplied by NEC.

It's interesting that neither Barco or Christie bother to supply any specs at all.

Mark

Posted by Steve Guttag (Member # 268) on 05-18-2018, 05:33 PM:

Christie does indeed supply numbers. They are in the user manuals and in their xenon lamp literature (what the output is in each model).

Barco supplies lumen specs for their projectors but not xenon brand specific. And it is always just the highest wattage lamp available for that model however, since they have 4 lamphouses over three styles of projectors, one can know what the lumen output is on the smaller lamps by just using the smaller projector. But yes, NEC does provide the most comprehensive lumen chart, though the numbers are rather inflated. Furthermore, note they never provide the "HS" style lamp outputs to compare a UXL-20SC to a DXL-20SN3. They leave that as a homework assignment. It is on the order of 20% less but it varies by wattage/lamp style. Some are closer to 15% less while others are more like 30% less. The other factor on film lamps is that their decay is MUCH faster than digital.

One place where the HS lamps work incredibly well are in the Barco "XL" style lamphouse as used in the DP2K-32B. That optical system really works with the HS style lamps. I was blown away at how well it worked. I had to provide a 2D lamphouse as well as 3D lamphouse and to get the light down low enough, I used a UXL-20SC lamp for 2D and it was STILL on the bright side and is all of the way to the warranty hours.

Nowadays (putting aside the decline of 3D in general), I would use the S/M lamphouse in the 32B and probably go down to a 1600-watt (or less) if need be.

Posted by Steve Kraus (Member # 476) on 05-18-2018, 08:02 PM:

Is there any difference between an Ushio bulb and a Christie bulb?

Posted by Mark Gulbrandsen (Member # 72) on 05-18-2018, 08:20 PM:

quote: Steve Guttag
Christie does indeed supply numbers. They are in the user manuals and in their xenon lamp literature (what the output is in each model).

Not on the Ushio page....

quote: Steve Kraus
Is there any difference between an Ushio bulb and a Christie bulb?

Only in who you deal with if you have a failure....

Posted by Steve Guttag (Member # 268) on 05-19-2018, 11:59 AM:

Ushio owns Christie. In a sense, Christie lamps are re-badged Ushio though that is an over-simplification. People like Jim Dukes have a lot of influence over the design of the lamps that go into the Christie product.

JFC Mark, just what is your point? Ushio isn't supposed to sell Ushio branded lamps for Christie Digital Cinema in North America (or possibly all of the Americas). If you go to the US site for Ushio, do they list CDXL lamps at all or are you going to so site out of your market where even the warranty will be different?

If you go to the Christie site:

https://www.christiedigital.com/SupportDocs/Anonymous/Christie-Xenolite-Lamp-Brochure-English.pdf

Here is the Christie brochure with the lumen specs in there. There is some lumen inflation there too. The specs presume "Over drive" (which can void the warranty) so plan on 10% or so less light than they are showing.

Posted by Steve Kraus (Member # 476) on 06-12-2018, 12:45 AM:

So since we cannot be certain the 1500W digital bulb, no iris, will be bright enough, I will just stick with the 2000W. And since I don't need the greater brightness or efficiency that a digital bulb provides, I am just going to get a film bulb as I have been using. Just to be sure, if I am going with Ushio that would be the UXL-20SC, right?

I was down to the last couple hundred hours on the existing Osram XBO 2000W/HS (film bulb) when I saw it was hitting 100% current just to make spec on Scope (and I usually like to go an fL or two higher). Then I starting noticing just the barest hint of flicker. So much for that bulb.

Fortunately I still had over 460 warranted (hypothetically) hours left on the prior bulb. I put that in, the light looks good and current could go a good deal back down. (More if I pull the iris.)

Here is the bulb I removed today. Not that I'm likely to ever see it but maybe Osram owes me a couple dollars.

Posted by Carsten Kurz (Member # 5396) on 06-13-2018, 07:32 AM:

Oh Steve, come on, that's such a boring decision after such a long discussion [Big Grin]

- Carsten

Posted by Steve Kraus (Member # 476) on 06-13-2018, 09:55 AM:

LOL It just got more interesting as I ordered the Ushio bulb from a vendor with a good price in nearby northwest Indiana only to have them ship some Brand Z equivalent which I'm going to have return when it arrives. They don't even carry Ushio yet have it listed on their site.

BTW is it possible that what I see on that Osram is the result of overcooling?

Posted by Kirk Futrell (Member # 5006) on 06-20-2018, 10:35 AM:

quote: Steve Kraus
I ordered the Ushio bulb from a vendor with a good price in nearby northwest Indiana only to have them ship some Brand Z equivalent which I'm going to have return when it arrives.

Oh no! That sounds like a Brian Vita move...

Posted by Mark Gulbrandsen (Member # 72) on 06-20-2018, 10:40 AM:

You really should be posting that Vendors name on here so others can avoid them....

I don't think Brian is still in business.

Mark