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Author Topic: HELP, uneven image Martin Risher Film Handler Posts: 13 From: Monroe, Washington, USA Registered: May 2004 posted 06-08-2004 12:26 AM                     Okay, so I'm fairly new at this theater and from what i can tell this is an issue since the projctors were installed, but has (supriingly) never been attended to. Here is the issue. Its simple... i think... The right side of the screen (projecter image) is higher than the left side. A 'angled' image if you will. I took a look at the turret housing to make sure it was locking okay and it checked out fine. I then checked the levels of the projector with a leveler and the entire machine is indeed 'uneven'. This was my first assumption so im not a COMPLETE retard... i hope... As i looked at it, the feet had little nut type things, and i figured they were used to raise or lower the projcteor at four points. I toyed with it a little bit and it seemed to have no effect. INFACT i turned the nut to the point where projector appeared to be 'floating' above the nut. I opened up the door which conseals the Xenon power supply and i found (on either side) a 'rail' guide type system which sort of curved from the top to bottom. It looked like this was attached to the frame of the machine. If I loosened it i feared it may fall and mak the projector much worse. Is there anything i can get to support or stablize it while working on it? So... I dunno if this helps... but i need to know how to lower the projector, or raise it. If it helps, its a STRONG HIGHLIGHT II projector. Can anyone help? Anywhere else I should look.  |  IP: Logged John Hegel Expert Film Handler Posts: 166 From: Lake Mills, Iowa Registered: Sep 2000 posted 06-08-2004 12:36 AM                        Any chance the anamorphic lens is twisted, or is it angled on flat too?  |  IP: Logged Bill Mantz Film Handler Posts: 91 From: Plano, TX Registered: Feb 2001 posted 06-08-2004 01:07 AM                     Is the image uneven on the screen when in flat and scope? If the image is uneven in both flat and scope, then someone has bumped the projector out of alignment. If the image is uneven in just one format then the aperture plate would need to be cut to even the image on the screen.  |  IP: Logged Daryl C. W. O'Shea Film God Posts: 3977 From: Midland Ontario Canada (where Panavision & IMAX lenses come from) Registered: Jun 2002 posted 06-08-2004 01:53 AM                        Nooooooooooooooooooo! Don't touch the plates. If it's just one format it's just a rotated anamorphic attachment or entire scope lens assembly. Even if the problem is with all formats, don't be touchin' the plates.  |  IP: Logged Wolff King Morrow Master Film Handler Posts: 490 From: Denton, TX, USA Registered: Feb 2004 posted 06-08-2004 02:11 AM                        I agree with Daryl. It's most likely a rotated lens. Once we got ours perfectly aligned, we put a little mark on them so as not to lose the exact positioning in the future.  |  IP: Logged Carl Martin Phenomenal Film Handler Posts: 1424 From: Oakland, CA, USA Registered: Feb 2002 posted 06-08-2004 02:22 AM                        yes, that's been bothering me lately on one screen as well, in both flat and scope. i figured toying with those "nuts" on the pedestal would solve it, but i haven't got around to it yet. quote: Martin Risher As i looked at it, the feet had little nut type things, and i figured they were used to raise or lower the projcteor at four points. I toyed with it a little bit and it seemed to have no effect. INFACT i turned the nut to the point where projector appeared to be 'floating' above the nut. did you turn the other nuts as well? it sounds like the center of gravity was such that the projector was just happily standing on 3 points rather than 4. probably not good to leave it that way.... carl  |  IP: Logged Mike Pennell Expert Film Handler Posts: 150 From: Tucson, AZ, USA Registered: Apr 2003 posted 06-08-2004 02:38 AM                     Martin, dont touch those "rails" unless you want to make your auditorium into a planetarium, they evenly move the image up and down on an axis. The weight of the power supply will quickly pull the back of the projector down without someone/something supporting it. If the projected image is indeed uneven and not just a twisted scope lens, adjust the projector by those leveling feet. You're gonna need to lower one side and raise the other. Go slow or even better have your tech take a look at it. on his next visit If you do it yourself level it with the flat lens in and match the aperture image to the masking, the scope should coincide. Or the problem could possibly be turret related .  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 06-08-2004 02:45 AM                     Yank the aperature plate and project an image on the screen. Adjust the frame knob to see if the frame line of the image is parallel with the deck, (floor) or at least parallel to the masking at the top or bottom of the screen. If you do this with a flat aspect ratio and the frame line is not perfectly horizontal, it might be time to make sure the projector is leveled horizontally. If the frame line is horizontal with the flat lense and not with the scope lens, then your scope lens has been twisted as others may have suggested. You can get it fairly accurate by using a frame line, lostening the lens collar and rotating the lens so the frameline is horizontal. But that's only after you checked to see what that frameline looked like with a flat lens. Some day if you would like, I will drop in and see what you have. You are only about 50 miles from me.  |  IP: Logged Martin Risher Film Handler Posts: 13 From: Monroe, Washington, USA Registered: May 2004 posted 06-08-2004 03:27 AM                     -[Deleted]-  |  IP: Logged Martin Risher Film Handler Posts: 13 From: Monroe, Washington, USA Registered: May 2004 posted 06-08-2004 03:28 AM                     Thanks all, I'll poke it around tommarow morning. Im pretty sure the issue remains with both formats, however i think it was more noticable in scope. Dont mark my words, I came in tonight just to check on responses. But yea, so I'll toy around tommarow and let you all know if it worked. I have a feeling the anamorphic lens may be the issue... dun dun dun... stay tuned...  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 06-08-2004 03:40 AM                     Ideally you should let your tech fix this. However knowing how the real world works (often techs are far too overworked to be willing to fix things like this), here's the best explanation I can offer. First off let's assume that the tech who set up this projection system knew what he was doing in at least the most basic sense. This means that he should have leveled the console while projecting a loop of PA35 film through the flat lens and achieved perfect level on screen before he started cutting plates and leveled (by twisting the lens) the scope lens. Assuming he did that properly, the others are correct do not go hacking on the aperture plate! You will only do more damage. You don't really need test film to verify this. Make yourself a loop out of a green band tomorrow. Remove the aperture plate and run the loop on screen through the flat lens. Rack the framing just enough to see the frameline project at the top of the screen. Is it level? Now rack it the other way so you can just see the frameline project at the bottom of the screen. Is it level? It should be. If not, reinsert the aperture plate and adjust the leveling feet of the console until it is. Be careful of two things. First make sure you don't end up with an aperture shadow on the screen when you are finished, and second make sure your console isn't wobbly from having the feet not quite leveled evenly. Now it's time to go after the scope lens. With the aperture removed, project that same loop on screen and perform the same tests. Is that frameline level as it is compared against the top and bottom masking? (Do note it is common for there to be keystoning in the image, especially on curved screens and stadium seating houses near the bottom. The goal is to get it as balanced as possible.) If not loosen the lens mounting screw and gently twist a little bit until it is level. (Be careful to make sure you aren't twisting the anamorphic attachment with the backup/prime lens sitting still.) Now lock it back down and reinstall your aperture. Do you see an aperture shadow? You shoudn't, but you probably will. From this point you will have to make fine tuning adjustments on your turret. You failed to give us any specific information on the projector head (a Highlight II is a lamphouse/power supply, not a projector), so that's about as specific as we can get. Odds are if you have that model lamphouse you have either a Simplex or a Century projector hanging on the front of it. The manuals are reasonably detailed in how to make those minor adjustments to the turret to get rid of the aperture shadow. Bear in mind all of the answers above are good advice (especially the part about the lamphouse angle "falling" if you loosen the bolts) and also that you need to check with your tech before you make any adjustments like this. Either he won't mind you taking care of it, or he will and he can get his butt to your theater and fix it himself!  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 06-08-2004 03:56 AM                     Brad's suggestion is similar to what I mentioned in an earlier post. As far as techs are concerned, tons of independents up here don't have a "tech" to tend to their needs. Techs are extremely rare up here in Washington State. Since Vern Klingman passed away, the only free-lanced techs I know of other than McRae is myself or Ken Layton. I can't speak for Ken, but I usually don't advertize myself as being available. Too much of a pain in the butt for a person my age. McRae is so badly overloaded he can't even see the sunshine anymore. Many theaters have to pull a tech out of ACE in Portland, and the cost is prohibitive because of road time and expenses to fix such a minor problem as you might have. If you have gears laying all over the floor, that's a different situation. Furthermore, sometimes I think Scott is so badly overloaded that it might take a good deal of time to get to you on minor things like you have. Scott does have some good people working for him, and I certainly endorse his company as being a being a reputable organization, and will serve you well. All in all, I know it is something you can do yourself if you know what the cause is. I'll still be happy to take a peek at it for you - at no cost other than maybe a cup of coffee. I'll at least mention what you can do about it. I am a tech. I have built projection booths and serviced projection booths for many years (too many, in fact)and have a very good track record of that. This would make a nice Sunday drive for me, as sometimes I get bored out of my skull. So this would solve two problems...your tilted picture and my being bored for that day. Email me if you want me to stop in.  |  IP: Logged Martin Risher Film Handler Posts: 13 From: Monroe, Washington, USA Registered: May 2004 posted 06-08-2004 01:09 PM                     Yea, I wasn't about to go hacking away at the apature plate, seemed a littl... mm... i dunno. But yea, I made a loop out of a trailer. I figured i could counter-act the 'slightly unevenness of the projector' by adjuting the anamorphic lens. and TADA! All is grand. I also checked out those 'nuts' i was talking about ealier, and lowered a 2nd one on the same side, yeah, the damn thing just hovered above the two... so i thought that was weird. But in anycase, the image looks pretty good now. So thats done and taken care of. Cool... Thanks for the offer Phil, I'll keep your name and email up in the booth incase McRae isnt able to make it out. I'll be sure we keep you in mind. Thaks again Weenie Man. [ 06-14-2004, 01:56 PM: Message edited by: Martin Risher ]  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 06-08-2004 02:38 PM                     You need to check the flat picture and see if it is off level. If it is, your quick fix to the scope lens may have given it the appearance of being level, but vertical lines will be diagonal. That's not the right way to do it.  |  IP: Logged Paul G. Thompson The Weenie Man Posts: 4718 From: Mount Vernon WA USA Registered: Nov 2000 posted 06-08-2004 10:37 PM                     Martin, be sure to do as Brad recommends on his last post. It is an echo of what I said much earlier. If the projector is not level horizontally, you have basically added an error to offset an error.  |  IP: Logged

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