Film-Tech Forum ARCHIVE: USHIO DXL-xxBAF/L Lamps

This is topic USHIO DXL-xxBAF/L Lamps - Is the "L" worth it? in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Monte L Fullmer (Member # 2797) on 06-30-2014, 11:58 PM:

Little help here:

Question to ask: What's the advantage of these "Long life" lamps outside of gaining "x" amount of extra hours?

?What did they do to these lamps: add extra gas, higher constructed tungsten electrodes, and similar?

Not too impressed since they can fail just like a standard "BAF" lamp. I had to pull a 40BAF/L that just broke standard 1000 hr warranty with huge three "ripple horns" on the anode electrode and with over 300 strike counts.

This lamp was experiencing hard strikes were we had to strike this lamp manually in our 23B Barco and had to do the pull (and hate that 6inch brass cathode end extension adapter one has to use in a 23B).

thx - Monte

Posted by John Roddy (Member # 7348) on 07-01-2014, 12:28 AM:

Are they worth it? I'd say yes. From what I've seen, they don't cost more than the standard life bulbs, and they're no less reliable. Yeah, it's true that some of them do crap out a little earlier than they're supposed to, but that's a standard feature of all lamps out there. It's a lottery when it comes to build quality.

That being said, I have changed lamps that made me feel guilty. They were past their insured hours, but still looked to be in perfect working condition. No flickering, no hard strikes, and power output that was still well within acceptable range. The only reason to change them is because they weren't insured anymore. The L-series bulbs seem to just help out in cases like that. Longer insured life means that good quality bulbs can comfortably be used for an extended time. And should they not hit that time, it's a bigger window to throw a warranty claim at 'em.

I've been using almost exclusively L-series at my site, and the vast majority of them haven't had any trouble reaching their insured hours. At the very least, they come pretty close before they start giving trouble.

Posted by Steve Guttag (Member # 268) on 07-01-2014, 04:03 AM:

For one thing, the "L" series has replaced the standard lamps so it isn't like there is a choice in the matter.

But if you look at the lamp decay curves...you'll find that the "L" series holds its light levels longer too. The decay is much shallower. That said, the "L" starts with a little less light than the original lamps but after about 25% of the life, it has more for the rest of the life.

The whole electrode design thing seems to be an evolving art in how to get the arc more stable and the heat dissipation better. You really can see it in the larger lamps.

I agree on the BAF style lamps in the larger "B" lamphouses...the long lamp adapter seems like an awful lot of weight on hte end when you are installing. That said, the "B" series lamphouse/and light engine really does get you quite a bit more light than the same lamp in a "C" series.

Note too...the new DXL-16BAF for the S2K projectors can be used in the C and B projectors and it is awesome in its light output...it is so much better than the DXL-12BAF...which seems to have a rather steep decay to its life. The DXL-16BAF has a much shorter arc since it was designed for the smaller aperture...but this efficiency helps out the larger systems too. The latest Barco firmware 1.12.160 adds this and the DXL-22BAF to the other projectors too. That could be handy if you have a DP2K-12C that seems a little undersized for the screen it ended up on.

Speaking of the new Barco firmware...1.12.160 also is attempting to improve the whole lamp striking and life thing again...again, they are working on the power supply algorithms.

Note, on Christie you still have a choice on their lamps...a Christie "SP" lamp is their long-life...however they do cost more but they start out with as much light as the standard lamp...they end up with more light at the end. The cost per hour is cheaper on the SP lamps too.

Posted by Monte L Fullmer (Member # 2797) on 07-02-2014, 12:59 AM:

Thx Steve for your comments, for now it really helped to clear things up with this issue.

I'll ask our techs on the 1.12.60 firmware upgrade since we're still on the older one in these units

I do believe, in an earlier comment that you posted, that the 65BA2 has a longer life brother being the 60BA/L. I'd like to get a bit more info on this lamp so I can present it and see if this can be suitable for a 65 ft wide screen, but with a short throw of less than 80 feet - house is more wide than long.

thx - Monte

Posted by Antti Nayha (Member # 4980) on 07-02-2014, 03:37 AM:

See this Ushio page. As you can see, the DXL-60BA2/L has 800 warranty hours compared to DXL-65BA2's 500. There's almost no price difference, so the 60BA2/L is a good choice unless you really need the few extra lumens.

The 60BA2/L is slightly less bright, but the light output should be more stable during the bulb's age.