Film-Tech Cinema Systems
Film-Tech Forum


Post New Topic  Post A Reply
my profile | my password | register | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum   » Operations   » Digital Cinema Forum   » What is the Recommanded christie bulb light intensity

   
Author Topic: What is the Recommanded christie bulb light intensity
Alexander Tarakin
Film Handler

Posts: 18
From: Israel - Ramat Gan
Registered: Aug 2012


 - posted 06-05-2018 11:27 AM      Profile for Alexander Tarakin   Author's Homepage   Email Alexander Tarakin   Send New Private Message       Edit/Delete Post 
Dear all,

Can someone please advice on what is the recommanded light intensity for Christie bulbs in a christie projector CP2220, CP2230, CP4230.

CDXL3,000
CDXL4,500
CDXL6,000

Thank you.

 |  IP: Logged

Dave Macaulay
Film God

Posts: 2106
From: Toronto, Canada
Registered: Apr 2001


 - posted 06-06-2018 01:05 AM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
Not sure what you're asking.
I think the number you get for "lamp brightness" in lamp alignment is undefined. Since this number is only used as a data point for light-loc there's no reason for Christie to calibrate it to a measured light level value in the light engine. As far as I know, they do not.
I don't know the typical value one might get from a given lamp. I've seen a fairly wide range but I've never noted the readings.
If you mean screen brightness values, these have no consistency unless the screen size and gain - plus projection geometry with a gain screen - are identical.

 |  IP: Logged

Alexander Tarakin
Film Handler

Posts: 18
From: Israel - Ramat Gan
Registered: Aug 2012


 - posted 06-09-2018 01:52 PM      Profile for Alexander Tarakin   Author's Homepage   Email Alexander Tarakin   Send New Private Message       Edit/Delete Post 
Hello Dave,

Let me explain please...
I have two christie projectors CP4230 with a CDXL-6000 bulbs.
The projection geometry and screen size are almost identical.
One projector is with an intensity of 54,000 and the other with 30,000.
The one with the 54K intensity projects a much sharper, clearer and more colorful image.
The one with the 30K is projecting a darker and less sharper and clearer image.

So, is there a chance that a reflector / UV filter / integrator rod or any other optics related parts should be replaced? or maybe the image quality difference is due to some other reason?

thank you.

 |  IP: Logged

Dave Macaulay
Film God

Posts: 2106
From: Toronto, Canada
Registered: Apr 2001


 - posted 06-09-2018 03:40 PM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
It may be that the prism is dirty. I haven't had problems with a Christie integrator. And "almost identical" means what? A modest change in screen HxW can mean quite a change in area.
Is one older than the other? Is one closer to a doorway where popcorn smoke wafts up from the lobby? I see a big difference in filter loading when popcorn smell gets to a booth, with the systems closest to the source markedly worse. Christies can get their light engine optics coated with this stuff, the LAD filter is pretty good but some gets through.
Inspect the collectors and folding mirrors, these get unfiltered air and soil faster than the prism.
Dirty prism and DMD surfaces drop brightness, contrast, and color saturation

 |  IP: Logged



All times are Central (GMT -6:00)  
Post New Topic  Post A Reply Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
 - Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.

© 1999-2018 Film-Tech Cinema Systems, LLC. All rights reserved.