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Author Topic: Picture not square on screen?! Joseph Muggio Film Handler Posts: 9 From: Dauphin, PA, USA Registered: Oct 2006 posted 11-26-2007 09:59 AM                     I first noticed this issue quite a while ago, but never thought to ask about this! As you are probably aware, as per the studio insert in the can of Enchanted, the first 11 minutes (the animation sequences) appear in the 'flat' aspect ratio, then changes to scope. During the 'flat' part of the film, the right side of my picture on screen has an inward slope, from top to bottom and makes the presentation look poor. It looks a little bit like a lopsided keystone, but the left side is straight and the right side isn't. Any ideas what might be causing this and how can I fix it?  |  IP: Logged Mitchell Dvoskin Phenomenal Film Handler Posts: 1869 From: West Milford, NJ, USA Registered: Jan 2001 posted 11-26-2007 10:34 AM                     Most likely cause is the projector is not dead center to the screen, and/or you are projecting at a angle. Rotating the entire lens will straighten out the right side, but will probably screw up the top/bottom so the picture keystones off the screen. You are probably better off leaving well enough alone.  |  IP: Logged Mike Blakesley Film God Posts: 12767 From: Forsyth, Montana Registered: Jun 99 posted 11-26-2007 10:39 AM                        We have this exact same problem and that's correct, it's probably because your projector is off center. When we plattered the booth and took out one projector, the techs took out the wrong one....the other one was much closer to the center of the screen. (Our booth has 3 ports, one for a slide projector.) I looked into rearranging the booth to put the projector into the middle port, but (as Mark G. would testify) it'd be a huge pain and cost thousands of dollars. I'm saving the money for the digital conversion because the problem is not noticed by 99.9% of the audience anyway.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 11-26-2007 10:40 AM                        Joe, is your projector located directly in the center of the screen or are you off-center by any amount? Especially if your throw is short, an off-center position will cause keystoning that is not even. The cinemas where a single screen has been twinned and the original booth is used to serve both screens will suffer seriously from this condition. About the only thing that can fix this would be if you had movable side masks -- you could start the opening "flat" sequence of the film with the mask close in to mask out the keystone edges. Just as the image goes to full width, open the mask to the scope position. If you don't have movable masking (typical of cinemas thrown together from single screens on the cheap), you're going to have to live the glaring reminder that the projector is badly off-center. But the one good thing this shows: your concern for presentation values -- good show my friend. If only more booths were populated with this kind of projectionist!  |  IP: Logged Blaine Young Master Film Handler Posts: 477 From: Kirkland, WA, USA Registered: Sep 2006 posted 11-26-2007 10:48 AM                     Motorized side masking fixes the issue, except whenever you get prints that do this, the studio always 'suggests' that you leave the masking open so as to not block the speakers. One has to wonder why this isn't a concern on flat 1.85 films. Of course, the entire point is rendered moot at the multiplex where I work. 16 houses and all screens maintain the same width for Flat and Scope, but actually lower the top masking for scope creating a SMALLER image! This practice has always ticked me off.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 11-26-2007 11:29 AM                        Good point Blaine --our masks are designed so that only the leading edge is constructed of a hard piece of masonite covered by ultra-black (a special, highly light-absorbent rayon plush fabric that makes any amount of light that spills on it almost totally disappear). The rest of the mask is made of black china silk, a material that is very acoustically transparent. The speakers are placed so that the hard edge does is not fall in front of them in any format position. The china silk is so acoustically transparent that the RTA shows only a negligible change in the very high frequencies when it is in place, so small a change that you can't hear it. Of course both the ultra-black and the china silk are much more expensive than the much cheaper velour that most theatres tend to use, so you generally won't find it used much. Which goes to the question: do the techs eq the house for the mask set in front of the speaker or not? Or do they split the difference?  |  IP: Logged Thomas Pitt Master Film Handler Posts: 266 From: Leeds, West Yorkshire, UK Registered: May 2007 posted 11-26-2007 01:51 PM                     We had a similar discussion with side masking on the beginning of The Simpsons Movie - people were suggesting you leave the side masking set to flat until Homer points at the audience and then move it out. Of course, this would only work with fixed-height screens. However, there was an insert in the Enchanted can saying that the masking should be set for scope for the entire duration of the movie (even the flat part at the beginning) In many cinemas, I've seen 'flat in scope format' pictures have a noticeable keystone on both sides of the image, regardless of whether they use horizontal or vertical masking! I've seen the following kinds of masking in use at cinemas: Side masking - two blinds moving in from the side Top masking - single blind moving down from the top Fixed width - two blinds moving in from the top and bottom Four-way masking - two vertical AND two horizontal blinds moving! No masking - flat films leave unprojected areas on the left and right!  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 11-26-2007 02:27 PM                        Yup, we've talked about masking before; in general, fixed height is the golden ideal. The whole concept of Scope is for the picture to get wider, not squat-er. Making it smaller is counter-ideal and should be relegated to theatres that are designed around physical constraints that make fixed height impossible, or for theatres designed by archetechs who've only designed gymnasiums. But if it is impossible to have fixed height, then top AND bottom masking is best of all evils. As for having both top and side masking, that seems over-kill if 70mm isn't involved. Of course the really sweet thing is to have lenses and a masking stop for 1.37 so that you can go from a square Academy cartoon or short to a full scope width, preferably with a Fox feature and the Fanfare playing. Making THAT switch will give even the most jaded projectionist an erection.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 11-26-2007 04:35 PM                     What kind of projector do you have, and do you have a lens turret on it? Often you can eliminate this with adjustments to the turret, just like how you can eliminate left to right focus problems. Non-turret machines can have keystone correction implemented as well, but it's not "free" like a turret.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-26-2007 09:12 PM                     Find the center of the screen, put a piece of masking tape on the bottom black masking (or a small strip of black tape if have floating screens..) border at dead center, get some PA-35 (RP40)test film, roll it in the projector with apertures out, shoot it through a flat lens and the vertical centerline of the PA-35 should hit the tape marking for machine center. If not square, you got some machine scooting to do, then recut new apertures to fit both formats. Now, if you got Centurys, there is that lens adjuster that can be used to center the lens to screen. And turrets are easy to get things to center. Thing with the scope lens is that you got to do a bit of multiple adjustments to get that lens to center - with azmuth along with vertical and lateral adjustments.  |  IP: Logged Robert E. Allen Phenomenal Film Handler Posts: 1078 From: Checotah, Oklahoma Registered: Jul 2002 posted 11-26-2007 09:35 PM                     Hey Guys: I've only scanned the responses so I don't know if anyone has addressed the issue but is it possible that his scope lens is not seated properly in his lens mount? I could get the same effect with a B&L in a single lens machine if I did not "rack" the lens in the right direction.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 11-26-2007 09:48 PM                     My fault in not reading the initial topic to his condition: Yet, a simple trick to find Scope center: Roll the FRAME a touch to where the frameline just barely shows up at the bottom of the screen. One will notice the convex curve of the frameline across the bottom of the screen. If one side of the curve is higher than the other on each corner of the screen, loosen the lens in the mount to roll the lens to make each end of the curve equal in height at each corner of the screen. If this is the case, then this should bring that right side to more square in the image. In fact, when the Scope lens to square, both sides should be just slightly angled out due to the keystone effect (trapezoid look) of the downward angle of the throw.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 11-27-2007 12:37 AM                     Sort of Monte, but not quite. Level the machine first using the flat lens!!! (Just rack a film out of frame if you don't have PA35 test film, but rack it from the bottom a foot, level the machine, then rack it a foot from the top and verify the leveling is still equal...if not split the difference.) Then and ONLY then rotate the scope in the lens holder if it is not level. That may be close enough to solve your problem, although don't be surprised if the apertures then are suddenly lousy. (There is more to it than this, but that is the basic procedure in trivialized form.) Also if your machine is indeed off center, that old fashioned trick of putting tape in the center of the screen is useless...unless you like cropping part of your image! Think about it. If your machine is off center to the left by a few feet and you have that white tape dead centered left to right on the physical screen, you will have more width on the right side of the projected picture than the left. As such if you go by that tape, you will end up cutting off a bit of information on the right side of the picture. I've never understood why everyone is so damn set on using that silly tape method, especially 2 projector changeover setups! Just use the markings on the projected PA35 and compare the left edge to the right edge. It is far more accurate. Anyway Joseph, can you possibly take a digital picture of your screen during that first 11 minutes? Alternatively if you are afraid the feds will knock on your door for posting an image shot off of the screen while you are trying to improve that movie's presentation, find yourself one of those scope trailers that have black matting on the left and right sides and make a loop out of the green band and photograph that. Being able to see how much it is off will help diagnose better. Also take a picture of your projector so we can see what you are running so the help will be more specific to your equipment. If you have a turret you are so in luck, because in a nutshell (again I am trivializing here), you can square off the projector to the booth wall (trivializing here people) and adjust the lens so the image is moved left to right or up and down to minimize or totally eliminate that keystoning. I ALWAYS go through this when setting up a new installation and then fine tune things with a fresh piece of PA35 and a set of binoculars to tweek all 4 corners to resolve the same lines. (Scope astigmatism should also be done through the lens and via binoculars to minimize chromatic aberration).  |  IP: Logged Frank Dubrois Jedi Master Film Handler Posts: 896 From: Cleveland, OH Registered: Mar 2005 posted 11-27-2007 11:16 AM                    Why do they even do this?? Didn't they do something like this with Galaxy Quest too?? Personally I think it looks bad having exposed screen. We even have ushers that close the masking because they don't know any better. In my opinion, it's simply not worth the effort for studios to be doing this.  |  IP: Logged Blaine Young Master Film Handler Posts: 477 From: Kirkland, WA, USA Registered: Sep 2006 posted 11-27-2007 01:07 PM                     "Galaxy Quest" and I think the entire first reel of "The Horse Whisperer" and all of the 'non-brain scan' sequences of "Brainstorm". The Widescreen LaserDisc of that one is a trip, bouncing back and forth the entire film.  |  IP: Logged

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