Film-Tech Forum ARCHIVE: Lamp compatibility with 35mm

This is topic Lamp compatibility with 35mm in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Bob Healey (Member # 1003) on 02-17-2012, 09:48 AM:

Not sure if this belongs here or over in the film forum since its relevant to both.

I've been helping the cinema at my old college do research in converting from 35mm to digital cinema over the coming summer (Swank has supposedly assured them they'll be able to get the content). What I'm wondering is if it is possible to use the same XBO 2000W/HSR Xenon lamps that are currently in the 35mm units (its still reel to reel) that they have a decent stock pile of in any of the current production D Cinema projectors.

I've been looking at NEC, Barco, and Christie's offerings and haven't seen a lot of detail regarding lamps, at least not the level of detail I'm accustomed to when dealing with halogen stage fixtures.

Thanks for any advice.

Posted by Steve Guttag (Member # 268) on 02-17-2012, 12:11 PM:

Christie 1.2" machines can use the CXL-20, CXL-30...etc lamps in their projectors. One may need a suitable adapter to get the spacing in the right range.

For the .98" offerings, Christie "made" though I don't know if they still do now, an adapter to allow the CXL-16SC lamp to fit. Christie now offers lamps in the 1400, 1600, 1800 as well as 2KW models for the CP2210 so they may not offer the adapter anymore.

Barco, on the DP90, 100, 3000 and the 32B can use an "HS" lamps from 2KW on up.

NEC projectors can use 2KW+ HS lamps in their machines (they supply an adapter).

Note, using Cinema lamps in DCinema may require altering the + lug of the lamp or constraining it since the cable length is often much shorter than for film systems.

Nobody publishes specs for how many lumens you will get from the Cinema lamps in a DCinema application either.

Posted by Bob Healey (Member # 1003) on 02-17-2012, 12:50 PM:

Thanks a bunch. Looks like Barco/NEC are the two main contenders at the moment.

Its currently 2KW XBO/HS in Xetron lamp houses - there's a stock pile of 3-4 of them at the moment. The 35mms aren't going away, all the policy snips will remain on 35mm for instance, and the money people would prefer to not have to keep 2 different stocks of $700 lamps, especially since at the present the 35mm lamps are run 24 hours/week max (struck an hour before first show, doused after final reel), and the digital I imagine will be run even less since the lamp won't be left on between showings.

Posted by Louis Bornwasser (Member # 3063) on 02-18-2012, 08:40 AM:

If (when) you go digital, $700 will feel like chicken feed. I woundn't worry about using up old bulbs. That will be the least of your expense and is a bad reason to buy a particular "system." louis

Posted by Bob Healey (Member # 1003) on 02-18-2012, 08:42 AM:

What other recurring expenses are associated with the operation of the projector?

Posted by Phil Ranucci (Member # 3820) on 02-20-2012, 04:39 PM:

I see that you're not really going to be using them that much, so bulb life isn't really an issue. Using the same lamps is a good idea, but not a deal breaker.
I hope you don't leave the 35 lamp on during a digital show just for policy trailers.
As to expenses, if you have an NEC or Christie the air filter replacements every lamp change will add up. Roughly $100. New Barco filters are cleanable. Remember that with digital you shouldn't go past warranty on the bulbs.
But at 24 hrs/wk, you'll only be changing bulbs every 2 years.

Posted by David Zylstra (Member # 4230) on 02-20-2012, 04:50 PM:

With quality lamps you should be able to get 25% over warranty (we use Christie lamps and have had zero issues with going +25%), if you look at the lamp charts from Christie they also show higher than warranty "expected" life from some of their CDXL lamps in certain projectors (of course going over warranty means no coverage for a damaged reflector if a lamp explodes).

Other costs include parts - while digital can be similar to 35mm in terms of reliability, if there are issues it could cost a lot more in digital parts vs. 35mm parts. You could also opt for a long term parts and/or service contract that gets you a fixed yearly cost for any repairs.

Posted by Bob Healey (Member # 1003) on 02-20-2012, 05:33 PM:

Thanks for all the info.

This is just a single screen, student run college cinema at a school with no performing arts/film program. I'm a sysadmin employed by the school doing research for the club due to having retained more knowledge of how the 35mm system worked 10 years ago than the current projectionist roster collectively knows. Currently working on questions to ask the vendor reps. If anyone's curious, the current setup is a pair of reel to reel Century units with a custom changeover relay system on pedestals with Xetron lamps + rectifiers, a Dolby CP-65 with DTS XD-10, and sufficient amp channels + crossovers to eventually bi-amp L/C/R. The plan is to buy 2D now, and upgrade to 3D when funds become available.