Film-Tech Forum ARCHIVE: Dimming on a chrstie 2210,2220 and 2230

This is topic Dimming on a chrstie 2210,2220 and 2230 in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by David Gibbons (Member # 10887) on 07-30-2019, 09:31 AM:

So I currently work on 26 projectors all ranging from 2210s to 2230s and they have begun to dim so my quick question is what are some possible solutions. After reading the manual for them it says that I need to run FL calibration after every lamp change but currently dont have acsess to a light meter at this time what are some of the ones you all use

Posted by Marco Giustini (Member # 4544) on 07-30-2019, 10:33 AM:

First question that springs to mind is: how do you know they are getting dimmer? The Christie fL reading is basically useless as it's not calibrated per format.

Posted by David Gibbons (Member # 10887) on 07-30-2019, 11:54 AM:

Just observation oner time really

Posted by Marco Giustini (Member # 4544) on 07-30-2019, 01:03 PM:

do you ever get your projector serviced? Is your service engineer carrying a colour meter?

Posted by Frank Cox (Member # 6258) on 07-30-2019, 04:53 PM:

Are your screens getting grubby and covered with crap?

Are your lamps being run over-powered or until they're good and dead?

Are you running the automatic lamp focusing program that's built into the projector whenever you change a lamp?

Posted by Carsten Kurz (Member # 5396) on 07-31-2019, 10:04 AM:

Hi David - if you are responsible for 26 projectors, it is probably a good idea, and the money should be there, to buy a decent light meter. For the job to check brightness over time, different solutions are available, some may cost only a few $, while a decent 'real' light meter is probably around 500 US$.

- Carsten

Posted by David Gibbons (Member # 10887) on 07-31-2019, 10:57 AM:

Ok sorry about not getting back to anyone but here we go

1 yes lamploc is run as part of the new Lamp install

2 lamps run at 100% power and only till warranty hours

3 yes we are looking at getting a light meter and was just wondering what other people use

Posted by Mark Gulbrandsen (Member # 72) on 08-02-2019, 08:19 AM:

I believe you answered your own question. One NEVER runs brand new lamps at 100% power until warranty. Any new lamp will grow dim quite fast. You are supposed to select a lamp so you can start off at ~70% give or take and increase the power gradually based on hourly usage over the warranty life to maintain screen brightness. Lamp Loc is supposed to do what I said above but in auto mode, but you should be starting out at much lower current and let it maintain brightness from there! I actually had a site with a 6KW lamp exlpode because of Lamp Loc. I set it at about 75% of max and the firmware did not tell us it was ACTUALLY AT full power. Right at its rated hours... K-Boom. Christie did cover the damage in all fairness, but I no longer trust Lamp-Loc. At least get a cheap Harkness or similar brightness meter and get yourself OUT of Lamp-Loc and above all get your replacement lamps properly sized by a qualified Tech! Your current tech isn't doing his job right.

Mark

Posted by Marco Giustini (Member # 4544) on 08-02-2019, 01:07 PM:

Aren’t you referring to Lite-LOC?

Lamp-LOC is the mechanical adjustment.

Posted by Mark Gulbrandsen (Member # 72) on 08-02-2019, 09:29 PM:

Yep!

Posted by John Thomas (Member # 6509) on 08-02-2019, 09:56 PM:

Yes, always run LampLOC, which is Christie's automated mechanical lamp focusing system. Not a bad idea to take a glance at the x, y, and z values LampLOC ends up with after it finishes. If you see any of them maxed out in the positive or negative direction it could be a sign that your reflector is misaligned.

Also take a look at your reflectors and dust them off safely. The reflective coating does degrade over time which will cost you light output.

As already stated, dust your screens and/or have them cleaned.

LiteLOC gets a bad reputation because people don't use it properly. Get a light meter and use LiteLOC.

For optimal lamp life, you should set your LiteLOC target after installing a new lamp: Once it's installed and LampLOC has been run, manually set the power somewhere between 75%-85%. If you are not getting 14fL (measured using a light meter -- NOT what the projector says) in this power range, you should be using a different size lamp. Set the LiteLOC target here and save the lamp file.

A xenon lamp's electrodes degrade over usage time. By setting the LiteLOC target in the 75%-85% range you are giving the lamp 15%-25% "room" to maintain good light as it degrades.

Make sure you when you save the lamp file, that the channels (flat, scope, etc) you regularly use are referencing that file. This is commonly missed.

Posted by Stephan Shelley (Member # 8587) on 08-02-2019, 10:34 PM:

If you have access to Christie's website they do have a couple of tech bulletins about this. Mostly about cleaning optics.

Posted by Mark Gulbrandsen (Member # 72) on 08-03-2019, 10:25 AM:

quote: John Thomas
LiteLOC gets a bad reputation because people don't use it properly. Get a light meter and use LiteLOC.

It also got a bad reputation all on its own because of firmware bugs! [Eek!]

Mark

Posted by Steve Guttag (Member # 268) on 08-03-2019, 10:51 AM:

Christie's implementation of Light-lock is wanting...its own douser fools it! When the douser opens and it can see the light again, it goes crazy trying to get it back in range. You'd think that it would put in checks that if the douser is closed/lamp is off...etc to not adjust the light. Additionally, it shouldn't worry about the light for a few minutes after it is turned on since the stability of the lamp has to be established first. Hopefully, the level it was at prior to turning off is close to where it needs to be when it comes back on.

Barco really wins on the "CLO" feature (constant light output). Theirs works and works well. Barco's automatic lamp adjustment is expensive and miserable in performance. It takes 15 or so MINUTES and never gets it as good as a human can in about 1 minute.

Conversely, Christie does win on automatic lamp adjustment where it gets it 95-100% right, 90% of the time (every once it a while, I've seen it get confused).

NEC...well...they win at providing a number that has no bearing on actual light output whatsoever! The higher number may or may not mean it is brighter or more even. More often than not, it will lead you down the wrong path. They don't have auto lamp adjustment either.

I have definitely noticed the light output degrading over time on all of the projectors. Cleaning those reflectors, even if they look good to the eye, really can make a difference. And, over time, depending on your environment, you might need to go through the entire optical chain to get some light back.

Posted by Mark Gulbrandsen (Member # 72) on 08-03-2019, 12:31 PM:

Steve,

All of which is why I say leave the dam light loc or what ever your favorite projector maker calls it.... turned off.

If you have a big plex get a simple light meter and compare it to your techs meter and maintain your brightness levels using the appropriate test pattern on a monthly basis.

Digital Screen Checker

Posted by Dave Macaulay (Member # 813) on 08-03-2019, 02:06 PM:

Barco CLO is effective on C and B projectors but more or less useless on S models. I can't understand how, but it senses the light level of the image - the sensor is at the light pipe folding mirror before the light engine just like the big boys. So when it activates, apparently only for a minute or two after a macro executes, it will crank the power to 100% if it's projecting a dark image.
Agree that Christie light-loc is barely useful.

Posted by Steve Guttag (Member # 268) on 08-03-2019, 09:06 PM:

Interesting...I don't sell the "S" models, as a rule. They have miserable contrast, were notorious for getting dirty internally, are inefficient on light, don't allow UPS to keep the electronics going. The DP2K-12C was our bread-n-butter projector...and Barco killed it. We're putting in the last ones off the line.

We're giving the SP4K-12 a strong look now but it is significantly more money.