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Author Topic: Barco projectors shaking Michal Matys Film Handler Posts: 70 From: Prague, Czech Republic Registered: Nov 2014 posted 05-12-2015 06:10 AM                    Hi guys, I wanted to ask if anyone of you have experience with shaking Barco projectors. You can see it on the subtitles, sometimes less sometimes more. We have several units which have this issue, I have checked if there are any faulty fans or something, its not the issue. The exhaust fan is not the issue as well since we have it hang on the ceiling. Anyone ever had those issues with Barco projectors? Thanks in advance for your ideas.  |  IP: Logged Edgar Prass Film Handler Posts: 32 From: Tartu, Tartu county, Estonia Registered: Mar 2013 posted 05-12-2015 06:22 AM                     Our 20C is rock solid and it's standing in a frame, which hangs down from the ceiling. The frame allows it to move a bit, so it's not completely fixed to the building itself. What's the direction of the shake? Horizontal? Vertical? Random? And what's the model?  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 05-12-2015 08:32 AM                     This is a known issue with the "B" series projectors. Any structural vibration is picked up by the weak lens mount - I've seen this when trucks drive by a theatre or when anyone walks by the projector, even when patrons are moving around. The fix is to set the projector pedestal on compliant mounts designed for the unit's weight: this makes them more prone to shaking if someone touches the projector or pedestal but eliminates the vibration from structure movement. On a solid concrete floor in a good rigid building they are dead steady, image shake shows up in wooden or less rigid buildings. The C and S projectors do not have this problem, so if it's not a B then look elsewhere.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 05-12-2015 02:22 PM                     Yep, Barcos lens vibration issues have been discussed a couple of times on this forum. There is a stabilizer retrofit kit from Barco. It doesn't solve the issue entirely, but for some projector/lens/throw combinations it seems to work. - Carsten  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-12-2015 06:10 PM                       I have had experience where the base feet lock nuts were not tightened. It was not the first place I looked but it solved the problem.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-12-2015 09:44 PM                     I've found that the current B-series lens stabilizer fixes the problem as well as any other projector, at this point. The current one uses a linear bearing to effectively prevent any lateral shake or vertical shake as well as ensure that the focus can only move in/out without any rise/fall. Now there was an earlier stabilizer that used a set of ball bearings that tried to press down on the top of the lens mount...that had varying degrees of success and it all depended on the down angle and the weight of the lens sticking out of the front. Generally, with Invision lenses, you are a gonner! They are quite heavy and stick way out of the front. The Minoltas never were as bad...they are much lighter and they don't really stick out that much on the B series.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 05-14-2015 07:42 PM                     I haven't seen that kit. The lens mount should have had linear bearings from day one. The rooms we had big trouble with have InVision lenses, the compliant mounts worked there after the first Barco "fix" didn't.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 05-15-2015 10:05 AM                     Here's the solution we found:  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 05-15-2015 12:09 PM                     What's that - burnt waffles? - Carsten  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 05-15-2015 12:50 PM                     I don't have the spec with me. We went to a vibration engineer and gave the system (projector + pedestal + server etc) weight. It is 3 layers of some specific rubber isolating pad material. I've used similar stuff under speaker cabinets but I think this is a different material.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-15-2015 02:06 PM                       I believe Mason make a whole range of isolator pads. I've bought similar devices on McMaster Carr. Pity a $50,000 projector that shakes that bad without resorting to burnt waffles.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-15-2015 02:12 PM                     The Barco part number for the current "kit" is R5905599. Watch out, Barco likes to try and charge for it. However, it is worth making your case that the problem is caused by faulty design to get it covered by warranty.  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 05-15-2015 03:16 PM                     I used B and C series on some open air venues where you can't put projector on normal rack stand, but must use some wooden crates and similar solutions......even, newer had this isue. Could it be that they improved this on latest machines which come out from factory? And Steve's point is wright, this would be definitly need to be covered by waranty!  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-16-2015 08:06 AM                     This part has only been out for about a year or so. I would suggest rejecting any projector that arrives without it. I can't imagine that they wouldn't be using it on all new projectors now. It isn't all that complicated/expensive and it does seem to address the issue reasonably well. I've seen shake on all projectors and sometimes it is really caused by the platform the projector is sitting upon causing it...that isn't the projector's fault. The B-series mount, however, due to the spring loaded bottom design without any real support for the lens just highlights the issue. Depending on the projector down-angle and the weight (and center of gravity) of the lens, you have a system that is "under-damped." You are less likely to notice this on the Minolta lenses since they are plastic/lightweight and don't put all of their mass out in front of the projector...but the Invision lenses...those things are VERY heavy and put the weight about a foot in front of the lens mount.  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 05-20-2015 02:47 AM                     I ahve one Invision lens on 19B, lens is a BIG one, since it's 2,2-5,3 (or something) ratio, but newer saw issue, and this projector is installed in hometown cinema for two years now, so watching movies often there  |  IP: Logged

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