Film-Tech Forum ARCHIVE: Laser projection

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Posted by Gary Lightfoot (Member # 8842) on 05-28-2015, 06:31 AM:

I've seen you guys mention you have laser projectors in some of your installs, and now they're becoming available in the home, some people are asking about about grey scale calibration - are any of you here noticing any colour drift from the phosphor or any problems with the phosphor wheels? It's being advertised as potentially only needing one calibration for it's life, and no need for light source replacement, but of course people are wondering if this is true in the long term or should they stick with lamps (UHP usually for domestic) for the time being.

As your projectors will have had more hours on them than any domestic versions, I was thinking that it would be people in the profession that will be seeing any teething problems that the new tec may throw up.

I guess the design of the pro kit would be such that it should be more robust than domestic, but sometimes the same problems occur, only after many more hours on the pro gear.

Cheers

Gary.

Posted by Marcel Birgelen (Member # 6801) on 05-28-2015, 10:41 AM:

First of all keep in mind that all current cinema systems are not phosphor wheel based but use native RGB laser sources.

Some smaller phosphor based machines might make it to the market in a later stage, but that's not yet the case.

From the handful installs out there, nobody can really tell you for sure how long those RGB sources will actually last and if the manufacturer claimed durability can really be achieved.

Posted by Gary Lightfoot (Member # 8842) on 05-28-2015, 11:21 AM:

Hi Marcel,

Thanks for the info, much appreciated.

Gary

Posted by Stephan Shelley (Member # 8587) on 05-28-2015, 12:21 PM:

The NEC NC1100L is a blue laser/yellow phosphor machine and is currnetly on the market. Again still to soon to have any history.

Posted by Steve Guttag (Member # 268) on 05-28-2015, 12:25 PM:

Marcel,

The NEC NC1100L has been shipping for over a year and is phosphor based.

Posted by Marcel Birgelen (Member # 6801) on 05-28-2015, 12:33 PM:

You're right, THAT NEC machine... Although I don't know anybody around here actually using it.

Posted by Carsten Kurz (Member # 5396) on 05-28-2015, 03:51 PM:

Yes, some NEC 1100L are in operation for a couple of months, but that is too early. Even if there is phosphor aging, just with these machines it won't become known too early, as hardly anyone will do frequent checks on machines where the manufacturer quotes a 20.000hrs light source life. If there are no catastrophic failures, it will take a long time... plus, compared to other parts of light engines, the phosphor converter will probably be rather cheap to replace.

- Carsten

Posted by Steve Guttag (Member # 268) on 05-28-2015, 04:52 PM:

The target user of these machines are also such that exact color balance is not at the high end of the priority list! How many years did we live with film theatres where NOBODY checked or adjusted color? There should be a reality check on just how important it is in a non-grading/critical environment.

Posted by Mark Gulbrandsen (Member # 72) on 05-29-2015, 09:25 AM:

The thing about the NC-1100 is that NEC doesn't really have a firm price on replacement of the laser components yet. This very question was posed to the NEC higher up's at the last CinemaCon. And as such I have completely shied away from that projector. They also do not know the true life span of those components yet. Laser is still five years off IMHO on any scale, at least as far as my customers are concerned. Once economical drop in replacement lamphouse's are available... then fine. I also really dislike the idea of being stuck with JUST laser.

Mark

Posted by Carsten Kurz (Member # 5396) on 05-31-2015, 04:41 PM:

At least in europe, they state a life span of 20.000hrs, and issue a warranty for 10.000hrs. From what I hear, color reproduction is not the best. I don't consider the NC-1100L an attractive offer. Power consumption is even higher than that of the NC900C. Brightness and contrast is the same as well.
The higher price is not nearly justified by the savings in UHP lamp replacements. As the lamp changing is a piece of cake, and there is fault redundancy in the Dual-UHP NC900C as well, where's the beef?

- Carsten

Posted by Gordon McLeod (Member # 33) on 06-01-2015, 09:06 AM:

"Wheres the beef" I have had only one UHP lamp make it to warranty most are failing between 300-700hrs

Posted by Scott Norwood (Member # 30) on 06-01-2015, 09:24 AM:

Stupid question: how do the laser machines fail? Do you lose brightness slowly over time as with LEDs, or does a laser fail completely, causing loss of a color? Does it work like a CRT, where most of the picture is actually produced by the green gun (laser), or is the wear on the three colors equal?

Posted by Carsten Kurz (Member # 5396) on 06-01-2015, 09:45 AM:

@Gordon - the NC900C lamps failing prematurely is done, they fixed it.

@Scott - both is possible. The 20.000hrs spec is based on gradual light loss, so, no failure, but expected degradation. Beyond that, of course, any lightsource can experience a full defect any time. The NEC 350W UHP lamps are warranted to 3000hrs, the NC1100L laser unit is warranted for 10.000hrs. The NC900C with it's dual lamps offers another redundancy path, at least if both lamps are actually operated. Wondering how much it would take NEC to implement automatic failure switch-over for one-lamp-operation?

- Carsten