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Author Topic: Barco/Kinoton with poor black
Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-27-2016 01:28 AM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
Hi there
I have a Kinoton S2 machine where black is in fact an awful brownish halo on screen. Apparently it's always been like that.
The optics have been cleaned but that did not improve the situation.
I guess there is nothing I can do without a new engine, I was wondering what could possibly cause that issue.
Thanks

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Dave Macaulay
Film God

Posts: 2321
From: Toronto, Canada
Registered: Apr 2001


 - posted 09-27-2016 05:49 AM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
What do you mean by "halo"? A light pattern, or a flat field of brown?
The Barco light engine contrast depends on the DMD chip used. I don't think Kinoton used the small chip systems, so a 2K 1.2" DMD projector should have pretty good contrast and blacks that look like dim gray on screen in a dark room. The 1.4" 4K chip contrast is not as good and black is a brighter gray, same as the .69" 2K ones (these are really 1/4 of a 4K chip).
A "brown halo" sounds like something is screwed up. I doubt if the electronics are doing that, but you can use the TI "ICP and Enigma Control Program" to "park" the mirrors and get the darkest black possible to see if the black pattern is somehow corrupt or one of the various correction matrices is off.
Dirt in the LE optics can cause contrast loss and higher black level: light is scattered by the dirt and some will go out the lens.The Barco design is not prone to internal contamination, though.

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Alan Gouger
Jedi Master Film Handler

Posts: 501
From: Bradenton, FL, USA
Registered: Jul 2000


 - posted 09-27-2016 08:01 AM      Profile for Alan Gouger   Author's Homepage   Email Alan Gouger   Send New Private Message       Edit/Delete Post 
If you run a multi screen momentarily swap the lens from another machine to eliminated lens as the cause. If its not the lens run a separate R,G,B test pattern to see if the issue is isolated to one of the DMDs. If the issue shows up on all test patterns it could be a bad integrator rod or light pipe adjustment. Also check your folding mirror for contamination.

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Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-27-2016 11:14 AM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
Hi,

It's a flat field of brownish grey. Basically the projector has poor contrast and black is in fact slightly brownish.

I did not think of the fold mirror thanks -- I'll have a look.

DMD's are 1.2", so it should be the best possible picture in the DLP world.

Swapping the lens is also a good idea. Unlikely but you never know. You don't want to swap the light engine to find out that is still showing the same issue.

Thanks!

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 09-27-2016 03:12 PM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
I don't remember selling one anywhere around Reading!

Fold and main mirror can be adjusted on a Kinoton, but you really do need the factory tool.

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Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-27-2016 03:34 PM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
isn't the fold mirror the one in the light engine? I've always called the other one 'cold mirror' as it cuts IR as well.

Do you work in Dunfermline only Pete? [Smile]

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 09-27-2016 03:57 PM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
As much as possible, yes, although I'm yanking your chain [Wink]

In the Kinoton lamphouse you can adjust the position of the main (collector) mirror and the cold (fold) mirror, prior to the light engine. It's best to adjust these using the Kinoton factory tool which clips to the light pipe cooling plate.

I can't think how these being misaligned would kill the blacks, but I guess one must be open minded.

I think I'd be looking at light pipe, notch filter, LE condition and lens.

Does yours have the heat filter or condensing lens between the fold mirror and the light pipe?

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Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-27-2016 04:59 PM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
heat filter.
yes, you never know what kind of black optical magic happens inside that block. That said I understand it's been like that since day one (don't ask!) so it should not be anything that has degraded over time. I have the feeling the RED DMD area is contaminated and that is scattering some red light around. It's a shame since as I said those should deliver the best picture in DLP world.
Thanks for your input.

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Pete Naples
Phenomenal Film Handler

Posts: 1565
From: Dunfermline, Scotland
Registered: Feb 2001


 - posted 09-27-2016 05:17 PM      Profile for Pete Naples   Email Pete Naples   Send New Private Message       Edit/Delete Post 
Generally they do put out a stunning picture Marco. It's a shame this one slipped and wasn't sorted.

Last year I attended one in Ireland which hadn't been serviced properly since install, it had been attended to by others who didn't know Kinotons.

When I left, the theatre owner was knocked over. It looked better than his other screens with Barco which were all about 2 years old. The Kinoton was at that point probably 5 years old and hitherto untouched. I'm not suggesting that the Kinoton is actaulyl any better than a Barco, but you're right it has everything going for it.

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Frederick Lanoy
Film Handler

Posts: 88
From: North of France
Registered: Aug 2009


 - posted 09-27-2016 05:43 PM      Profile for Frederick Lanoy   Email Frederick Lanoy   Send New Private Message       Edit/Delete Post 
Marco : is it always bad during a whole movie ? Or does the problem "evolve" (getting better, worse...) ?

I experienced a very troubling problem with a DP3000. The image looked really awful (no contrast, poor colors...) but only during the five first minutes of the trailer. Audience complained then... no problem anymore. Although, i did not fix anything.

Actually, there was a leacking of cooling liquid in the engine. With the heat of the lamp, it had evaporated quickly within the first five minutes of the show. We had to change the engine.

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Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-28-2016 01:30 AM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
Hi Pete
Sure I know the projector should be able to deliver a very high quality picture, that's why it's disappointing to see a picture worse than a the one that a 0.69" can deliver!
Frederick
No, the issue is constant as far as I can see.

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Marco Giustini
Film God

Posts: 2713
From: Reading, UK
Registered: Nov 2007


 - posted 09-29-2016 01:29 AM      Profile for Marco Giustini   Email Marco Giustini   Send New Private Message       Edit/Delete Post 
The lens is not guilty. I tried a different one and the issue followed the engine.

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