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Author Topic: Stuck Blue Pixels! Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 12-02-2014 04:37 PM                     Would be interesting to see what happens when convergence is adjusted in this case? - Carsten  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 12-02-2014 04:39 PM                     Here you go. They do look like dead pixels (but blue)! These are calibration colours, generated on the formatters. Barco suggested a light engine swap of course. I don't understand why blue has an irregular shape, and the whole thing does not make any sense to me.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 12-02-2014 04:44 PM                     I'm wondering if it isn't something "in focus" but in the light path...input or output of the integrating rod that is obstructing the light...this would make blue be perhaps more out of focus. As to refurbing the light engine...sure, to the best of my knowledge, they all will do that for a fraction of the cost of new...BUT you have to buy that first one or be down while they do the R&R. For some, I hear it can be up to 8-weeks. If you have a fair number of screens...then it would make sense to have a spare light engine...when one goes...put the spare in...get that fixed and put it on the shelf for the next one. Naturally, this scheme works best if you have all of the same model of projector so that the same engine is used in all.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 12-02-2014 04:55 PM                     Steve, Maybe. Had it been a shape with sharp edges, I would have looked on the integrator rod or around it. But exactly the shape of TWO pixels?  |  IP: Logged Gavin Lewarne Master Film Handler Posts: 278 From: Plymouth, UK Registered: Aug 2009 posted 12-02-2014 06:41 PM                     isn't blue the most "out of position" dmd in the light engine? ie, it has to have more convergence adjustment to get it in line with green (fixed) and red  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 12-02-2014 08:33 PM                     quote: Steve Guttag As to refurbing the light engine...sure, to the best of my knowledge, they all will do that for a fraction of the cost of new...BUT you have to buy that first one or be down while they do the R&R. Nope. NEC has them ready to ship out as needed on an RA. You send in a P.O. for 20 grand they ship you the advance replacement prism. Strong also does limited repairs to them as well. But very limited. Mark  |  IP: Logged Marcel Birgelen Film God Posts: 3357 From: Maastricht, Limburg, Netherlands Registered: Feb 2012 posted 12-03-2014 02:07 AM                     This looks like someone shot with a VERY powerful laser at your projector and managed to just burn those pixels, and since blue was a bit out of focus, it hit more of them... Yeah, it's somehow totally bollocks, but it just can't be something else in the light path, which happens to be neatly in focus and perfectly pixel shaped but has another shape for blue than for red and green... Does anybody know if TI implements (hidden) features to alter the behavior of individual (sub)pixels? And just out of curiosity, does this theater, maybe, have a laser show installed?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 12-03-2014 06:51 AM                     So after the 20-grand...then what...do they credit you back once your bad one comes in? It is a R&R or a Repair Exchange?  |  IP: Logged Ioannis Syrogiannis Expert Film Handler Posts: 147 From: Reykjavík, Iceland Registered: Jun 2005 posted 12-04-2014 01:43 AM                     quote: Gavin Lewarne isn't blue the most "out of position" dmd in the light engine? ie, it has to have more convergence adjustment to get it in line with green (fixed) and red If I am not missing something concerning the earlier models, the Barco light engines have no fixed green DMD. Only blue and, in case of the S series, red. I would go for the "burned by a laser" explanation, but it doesn't quite explain the non-exact blue gap. It is true that blue light is hard to focus. Yet, if the pixel edges are distinguishable, so should be the burned micro-mirrors' gap. The possibility of a bended (instead of non-working) micro-mirror, that only sends light for half a pixel is extremely low.  |  IP: Logged Marcel Birgelen Film God Posts: 3357 From: Maastricht, Limburg, Netherlands Registered: Feb 2012 posted 12-04-2014 02:19 AM                     To me the blue pattern still looks like 6 fully dead pixels, but out of focus. It looks like a cross with an extra dead pixel at the bottom right. Maybe the picture itself also is also somewhat out of focus (although the screen perforation doesn't look like it's more out of focus than in the other pictures), which may add to the blurriness. In the two previous pictures, you can clearly see the raster, in the blue one, it's much less evident, so something is clearly out of focus and most probably the DMD, which easily explains the soft edges. It also somehow makes sense (to me at least): If a high power, focused laser beam would enter the lens from the other side, it would focus this beam even more. Since the blue DMD is somewhat out of focus, the beam ends up being broader on this DMD than on the other two. Still, this kind of damage could never come from something like a simple laser pointer. That's why I asked about the laser show. Maybe if somebody was playing around with it and a high energy laser beam ended up shining directly at the lens for a prolonged time (maybe someone even liked how it reflected back from there ), it could be just enough to burn those mirrors in their off position. Although those mirrors clearly can cope with a lot of light and heat, if you do the numbers, you'll see that every mirror only reflects a few mW of light during production. A powerful highly focused laser beam could, potentially, deliver a far higher punch.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 12-04-2014 12:31 PM                     quote: Steve Guttag So after the 20-grand...then what They credit you the difference between the 20 grand and what it cost to repair the one you sent back in that was bad. Average is 6 to 8 grand and 2500.00 cleaning charge if it is full of popcorn oil or crud and has to be completely broken down. Certainly NOT the end of the world type pricing! Marcel... There is always one that ends up out of focus because of physical constraints of the prism. With Christie I believe is the red chip that's in a slight blur. Mark  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 12-04-2014 01:49 PM                     That's an interesting hypothesis. I'll ask for the lasers.  |  IP: Logged Aleksandar Obradovic Expert Film Handler Posts: 125 From: Belgrade, Serbia Registered: Oct 2012 posted 12-05-2014 07:06 AM                     Hi guys, I am reading this conversation and i have some (little bit off-topic) question: Can someone adjust DMD's manually (Barco DP100) if adjustment screws are not enough. Point is that i can not adjust convergence on mentioned projector with provided 6 screws on top of LE because they allow you +/- 10 pixels and i need 40-50 pixels at least. LE was teared apart for cleaning (cooling liquid was spilled inside all over DMD's - broken pipe of cooling system inside LE) and then re-assembled again from scratch. After projector boot-up i have tried to adjust convergence but was unable for earlier mentioned reason. Any good/bad idea? BR Alex P.S. How much do technicians in your area/country charge for this "operation"?  |  IP: Logged Marcel Birgelen Film God Posts: 3357 From: Maastricht, Limburg, Netherlands Registered: Feb 2012 posted 12-05-2014 08:23 AM                     Do you have this misalignment with just a single color or with multiple colors?  |  IP: Logged Aleksandar Obradovic Expert Film Handler Posts: 125 From: Belgrade, Serbia Registered: Oct 2012 posted 12-05-2014 09:05 AM                     Both Red and Green DMD's. Blue one is in place (it is fixed like someone said in one of previous posts) and looks ok. BTW Does someone have information who repairs/cleans LE's, LVPS, etc. in Europe? I am talking about projectors outside of warranty BR Alex  |  IP: Logged

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