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Topic: Lamp Question

Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 04-24-2007 11:50 AM

Just a follow-up. I received a replacement bulb from LTI and have installed it. The lamp burned for several hours with no problems thus far. Now hopefully I can get at least 2400 hrs out of this one. [Razz]

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-24-2007 01:16 PM

quote: Jeremy Weigel
Now hopefully I can get at least 2400 hrs out of this one.

.. not a good sign when you're hoping to get this amount of hours on an LTi esp. when the warranty of these Helios is only set at 1500 hrs.

(Think on getting your company to switch to Christies - warranty is 2000hrs and life expectency well garnishes over 4khrs..saving some money there in the long run...)

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 04-24-2007 03:31 PM

Actually they prorate up to 1800 hours with 100% up to 900 at least that is what I was told by my supplier. I switched from Osrams to the Helios just to try them out (1 1/2 years ago) and so far I've been relatively pleased with their overall performance say for this bulb and a previous one that exploded with just a couple of hours on it (which was the first exploded bulb I've ever had). The warranty claim process went very smooth with the first bulb and so far this one has gone smooth. The only major drawback I've seen is that they don't have as long a life, which I'm guessing is due to less gas in the bulb?

As far as switching to Christies, I actually just ordered one last week to try it out after reading several posts on here.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-26-2007 01:34 AM

Hmm....Let's do a comparion below and you be the judge:

LTI - (LTIX-2000w-HEH) taken out with 2315 hrs. Bulb suffered hard striking, cloudy envelope and hard flickering on removal due to massive cracks in the anode plug. Just managed to get past warranty to consider this a bust and a throwaway. Cost of bulb from dealer $435.00 new

Christie (CXL-20R) taken out with 5400 hrs. (and actually hated to pull this out since I had clean strikes, clear envelope, pleasant light and started to lightly flicker due to the ripple "horns" on the anode plug..). Cost from dealer $495.00 new

I have this Christie listed as a spare if needed. You ought to see the pile of LTI's (standard LTI's, not the Helios variety) that I have in storage waiting to be busted..and sadly, none of them made warranty, but just had hours on them to not make the pro-rate worthwhile.

As we can see how the math runs then - who is more valuable.

quote: Jeremy Weigel
which I'm guessing is due to less gas in the bulb?

The gas is the same in all makes of bulbs-they have to have a certain pressure for operation.

The big problem with other makes of bulbs outside of Christie and Osram is that they don't use the most purest tungsten for both the anode and cathode pieces in the bulb.

True, they use the purist form of Xenon gas, but the quality of the tungsten has to be on that same plateau. Tungsten quality is dependent on bulb longetivity. If the tungsten isn't pure, it breaks down after a certain amount of age due to decaying factors-like the cracks in the anode plug of an LTI bulb.

..- Monte

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 04-26-2007 03:08 AM

Assuming that LTI uses the same quality of tungsten in both their standard bulbs and helios why rate the helios to 1500hrs while their standard bulbs are rated to 2400hrs (which is the same for Osram last I checked the paper work). Just looking at the helios it appears that there is less cubic space which would take less gas to reach the same pressure in the bulb.

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Chris Slycord
Film God

Posts: 2986
From: 청주시, 경북도, South Korea
Registered: Mar 2007

posted 04-26-2007 03:24 AM

Why would you assume they use the same quality of ANYTHING in their cheap bulb?

If they put the same quality of it into the bulb it would most likely cost about the same to make (they have to make a profit). So the more expensive bulb is expensive because it costs more to make. One area you can save $ when making a bulb is in using a lower grade of tungsten.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-26-2007 03:34 AM

quote: Jeremy Weigel
it appears that there is less cubic space which would take less gas to reach the same pressure in the bulb.

Nope. Helios uses the same volume amount per say (sorry, should have said this above - "volume of xenon gas" - which all bulbs have per given wattage instead of comment on pressure.. my bad there). Thus, with the smaller envelope, the gas pressure is higher at cold. Also, the quartz is a bit thicker to handle the increased pressure at hot.

Why the warranty is lower on a Helios than a standard LTI bulb of the same wattage.

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 04-26-2007 05:55 PM

Ah, I see. Well, I took the proration on this one since it cheaper to do so since the proration peeriod had just started. I have a Christie on order and if it stays as clear and stable as the one you have for that long (5400 hours would equal roughly 2 1/2 years of use for us) that would be awesome! I usually barely get 3000 hours out of an Osram and they are usually extremely cloudy. In fact, the one Osram I have left in service right now has just over 1500 hours and is clouded up fairly well already, but the arc is stable and has decent light output.

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-26-2007 07:01 PM

quote:
....5400 hours would equal roughly 2 1/2 years of use for us - that would be awesome!

Gee, wish we could make bulbs last that long, but when you're doing daily matinees 7days/365/yr, this bulb with 5400hrs on it was in the console for 13 months.

I saw one Christie 2k bulb in a Christie SLC consoles with over 8k hours on it. Was installed 6 yrs ago when he bought the console...and still had great light. I did recommend to the owner on a replacement real soon, in which he did the following month.

Course, we need to back one step on how is your exhaust system? Is there enough draw coming out of the lamphouse area where the bulb ends aren't darken due to low airflow? If you had an airmeter, the CFM's drawing out should be almost at 1000CFM's for a good exhaust flow out of the lamphouse. Are the bulb end blowers doing their thing, or is this airflow at an hinderance?

Thus, wonder if you have a weak exhaust system why the cloudiness of the Osrams since they can be extremely sensitive to the cooling factors..

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Louis Bornwasser
Film God

Posts: 4441
From: prospect ky usa
Registered: Mar 2005

posted 04-26-2007 07:11 PM

FYI: On Osram, the warranty period is the point in the design where light loss equals 20%.

Most bulbs try to "match" Osram in terms of actual warranty and per cent of pricing. (Your actual mileage may vary, etc.) Louis

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Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 04-26-2007 08:10 PM

quote: Monte L Fullmer
Gee, wish we could make bulbs last that long, but when you're doing daily matinees 7days/365/yr, this bulb with 5400hrs on it was in the console for 13 months.

I saw one Christie 2k bulb in a Christie SLC consoles with over 8k hours on it. Was installed 6 yrs ago when he bought the console...and still had great light. I did recommend to the owner on a replacement real soon, in which he did the following month.

We only run one matinee and one evening show when our local schools are in session during the week, one matinee and 2 evening shows on Fridays and full schedule on Sat and Sun and we don't even start a show unless someone actually buys a ticket during week aswell (that cuts down on wear and tear too).

quote: Monte L Fullmer
Course, we need to back one step on how is your exhaust system? Is there enough draw coming out of the lamphouse area where the bulb ends aren't darken due to low airflow? If you had an airmeter, the CFM's drawing out should be almost at 1000CFM's for a good exhaust flow out of the lamphouse. Are the bulb end blowers doing their thing, or is this airflow at an hinderance?

I have scheduled for our yearly HVAC check-up and have requested them to also check the CFM on the consoles as well. As for the end blowers, I found out that my Super Highlight consoles have a X-60 lamphouse design if that give you any idea on how the end blowers are set up.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 04-26-2007 08:48 PM

quote: Monte L Fullmer
I saw one Christie 2k bulb in a Christie SLC consoles with over 8k hours on it.

There is a Christie CXL-20 in St George, UT at 19,480 hours and counting (in a Christie SLC Console).

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 04-26-2007 09:06 PM

acording to several sources there is only one source for the tungsten in the electrodes to start with and all but ushio(christie) use the same doping of thorium
so it is an issue of quality build that and cost compared to life expectancy is an issue
yes some lamps last almost for ever, but is the business model that everyone uses or is that the one most want
there is often more in numbers than meet the eye
so buy several cases of 7mx9" neg and 8mmx14 positives and move into the next level [Big Grin]

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Jon Miller
Jedi Master Film Handler

Posts: 973
From: San Diego, CA, USA
Registered: Sep 1999

posted 04-26-2007 09:59 PM

quote: Mark Gulbrandsen
There is a Christie CXL-20 in St George, UT at 19,480 hours and counting

I'm sure the lamp is regularly cleaned and rotated and I'm fully aware of the SLC console's lamp longevity reputation, but why would they want to hang onto a lamp some 14,000 hours past the Russian-roulette stage? [Eek!]

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 04-26-2007 10:12 PM

quote: Gordon McLeod
so buy several cases of 7mx9" neg and 8mmx14 positives and move into the next level

(..now that's good light to experience - natural arc light from earthen materials within the rods....)

quote: Jon Miller
but why would they want to hang onto a lamp some 14,000 hours past the Russian-roulette stage?

Yes, that is amazing that a bulb can last that long, but just wondering if the owner is just plain cheap to buy a new one, not educated on the dangers of the "Russian Roulette" syndrome upon removal, or just plain logical in seeing as to leave it alone as long as it's functioning normally with no problems...

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