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Author Topic: Moving a Projector Sally Ann Burgess Expert Film Handler Posts: 120 From: Queenstown, New Zealand Registered: Apr 2008 posted 08-20-2009 08:37 AM                     Right, on one of our Kinoton FP30 projectors, the image is never fully focussed across the entire screen. If we play a trailer that is letterboxed, the black "bar" at the bottom is taller on the left than on the right. The top bar is even all the way across. I think the projector needs to be physically moved but it won't be easy and I'm a bit concerned about aligning the lamphouse with the projector properly. It's funny because we have another screen the same size and same projector and the same throw, and the picture is always really clean compared to this other one. I have been lent some RP40 to help me out but just wanted to know if there was some advice anyone could give me who has experienced the same thing.  |  IP: Logged Andy Bajew Expert Film Handler Posts: 136 From: Bellaire, Texas Registered: Jun 2009 posted 08-20-2009 08:44 AM                     My theater has issues with pillarboxing where you can tell how uncentered the screen actually is. I am not entirely sure exactly what you mean about only the bottom left being higher but the top being fine. If I am not mistaken, wouldn't something like that be the lens that has become slightly rotated? Sort of creating a more diamond-type shape? However, if it is the moving of the projector you really want to know about, I have done this several times. If you find out you only need to pivot to fix the problem, I typically can use my foot to raise the back of the lamphouse and pivot with my hands. On two occasions I needed to move the lamphouse back and right a few inches--that required me and 3 other guys. You can always get two really strong guys and have them do a pivot thing where they alternate between moving the front and back.  |  IP: Logged Sally Ann Burgess Expert Film Handler Posts: 120 From: Queenstown, New Zealand Registered: Apr 2008 posted 08-20-2009 09:13 AM                     Thanks Andy. What I meant about the height of the black bar on the LHS is just that the bar is slanted down toward to RHS of the screen. And since we are currently showing Inglourious Basterds, the subtitles are sloping down too! The lamphouse is on metal legs but the projector was bolted to the floor. I say "was" because I have removed the bolts. I'll mark the carpet to show the projector's/lamphouse's original positions. Did you move the projector whilst playing a loop of RP40?  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 08-20-2009 09:23 AM                       I'm not familiar with Kinotons, but I've never seen a projector that was actually bolted to the floor. You sure those weren't the levelling feet you removed? They're normally adjusted in pairs, to yaw or tilt the projector by small amounts. You can use them to split the difference in the keystoning on your screen. You'll probably have to re-file aperture plates as well, after you change the levelling.  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 08-20-2009 09:35 AM                    First thing you want to do is project the RP40 using the flat lens. Make sure the bottom horizontal lines of the RP40 are straight and parallel with the bottom of the masking. If your projector sits with an angle you will have a keystone effect at the top lines of the RP40 image. Make all of your projector position adjustments with the flat image. Next use the scope lens and check the horizontal lines on the bottom of the RP40 image. if they are not straight loosen the collar that holds the lens and adjust the scope image by turning the complete lens until the bottom lines are as straight with the bottom of the masking as possible. Once again if you have a angle on the projector you will have a bit of key-stoning at the top of the image. Make sure that you refocus the lens in the barrel before tightening the collar back down. You will also need to cut new plates for flat and scope after doing the adjustments. If your keystone is to severe you can do what Tim says above and split the difference between top and bottom.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 08-20-2009 10:29 AM                     quote: Tim Reed I'm not familiar with Kinotons, but I've never seen a projector that was actually bolted to the floor. You've never worked on the West Coast then... Some locations require it by code for earthquake reasons.  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 08-20-2009 12:38 PM                        What Darryl said. Bolting the machines to the floor is code in Massachusetts, but I've never actually seen it done in practice. Actually, I have never seen a fully code-compliant booth here. Some don't even follow the basic safety requirements. Of course, the new ones all follow the handicapped accessibility requirements, right down to braille lettering on the doorplates. If I were going to pick and choose which codes to follow, I would personally pick the safety code over the handicapped code, but that's just me....  |  IP: Logged Andy Bajew Expert Film Handler Posts: 136 From: Bellaire, Texas Registered: Jun 2009 posted 08-20-2009 12:56 PM                     quote: Sally Ann Burgess Did you move the projector whilst playing a loop of RP40? Both times I moved the projector I left the lamphouse off--I was too worried about the bulb suffering damage or exploding if any of the movements were too rough on the housing. I did all the final adjustments, focus and mirror adjustments after the projector was moved near the spot I needed it to be.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 08-20-2009 01:24 PM                     I move the projector with the bulb and machine going-not going to hurt anything. How you gonna find center without any visual guides? But true, get the RP going without aperture plate and mark the center of the screen to align up with the center vertical line of the RP-40 display that is being projected on the screen. Then use a prybar at the rear of the base so you can lift the rear end a shad to pivot the rear end around to get front to center.. But, do the RP first to see where you're at before your Herculean employees want to excersize their muscles -Monte  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 08-20-2009 02:52 PM                     Sally, is this a changeover house? What you describe is the left projector in a 2 projector setup...or your single port window is not centered with the screen. There is little you can do. Inglorious Basterds is a scope movie, so there is a good chance your anamorphic lens has slipped in it's mount and simply needs to be rotated back level. There is a quick and dirty way to make this look decent (assuming the system was originally setup properly). Run a FLAT letterboxed trailer and re-level the feet on the Kinoton so that the bend is equally off on top and bottom (again when running a FLAT letterboxed trailer through the FLAT lens). That will get your projector leveled as best as it can. Then use a scope pillarboxed trailer and run through the scope lens and physically rotate the lens until the side bars are parallel to the side masking as best as possible (a similar effect will be seen, meaning not truly parallel, so just balance it as best you can). At this point you will see if your aperture was cut poorly and might require a tech to re-cut it, but the lenses will be dangerously accurate without having to use test film.  |  IP: Logged Sally Ann Burgess Expert Film Handler Posts: 120 From: Queenstown, New Zealand Registered: Apr 2008 posted 08-20-2009 04:05 PM                     Thanks for all the advice, fellas. Very much appreciated. Brad it's not a changeover house. I have a couple of flat letterboxed trailers I could use, not sure about scope pillarboxed ones but am on tonight and will have a rummage and play with the lens as best I can... Cheers.  |  IP: Logged Sally Ann Burgess Expert Film Handler Posts: 120 From: Queenstown, New Zealand Registered: Apr 2008 posted 08-21-2009 11:50 PM                     OK so I needed a bit of help levelling the feet of the projector today, I used some cardboard and now the line at the bottom is straighter than it was. I played a letterboxed trailer loop and adjusted the lenses to get them as focussed as possible, we don't have anything pillarboxed or scope. There is quite a lot of bleed onto the RHS of the masking (nearly a foot) and on the LHS there is a black shadow that comes into the picture by about 6 inches or so.  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 08-22-2009 02:20 AM                        Just aim the projector a bit more to the left. But before you do, make sure the aperture plate is seated properly.  |  IP: Logged Andy Bajew Expert Film Handler Posts: 136 From: Bellaire, Texas Registered: Jun 2009 posted 08-22-2009 02:25 AM                     The shadow you describe seems like it would be caused from the filing of the aperture plate. I had to file down one of my aperture plates just earlier for the exact same problem. Usually it's caused by the back part of the aperture not being completely straight with the front--filed at an angle. The bleeding on the masking, I would double check the position of the projector. If it is minor, try just shifting the back of the projector right(pivot on the front right - if you are looking at the back), or just move the entire projector to the left some-that would solve both problems.  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 08-22-2009 02:52 AM                     It's not possible to eliminate aperture shadow completely. That's why the picture always projects a little bit onto the masking, to hide the aperture shadow. Aperture shadow arises because the aperture is not in the focal plane of the film. It is some distance closer to the lens than the film itself (depending on the projector model...). Yes, it can be reduced by "backfiling" aperture plates, but that's not a a good idea for the inexperienced (plus, it's hard to recover from a mistake). Try to center the image on the screen. If you have 6" of shadow on the left and 12" off on the right, then it sounds like you'd be perfect if you shift the image 6" to the left. Then you'd have your 6" of shadow projecting on the masking (where it belongs!) on the left, and if you have the same amount of shadow on the right (as you should), that will also all be on the masking. --jhawk  |  IP: Logged

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