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Author Topic: Mission Impossible 4 in wrong aspect ratio? And more... Peter Castle Expert Film Handler Posts: 220 From: Wollongong University, NSW ,Australia Registered: Oct 2003 posted 02-03-2012 10:19 PM                     Unfortunately the vertical resolution is not 1080, as the original source material (the file) is only 848. The server (or the projector) has to scale the vertical dimension by 1.25 before the anamorphic stretches the horizontal physically. Of course if the files were anamorphic - in readiness for expansion horizontally - then we'd get that full vertical resolution (not likely). So we'd end up with 848 vertical spread over 1080 DLP pixels electronically, and 2048 horizontal pixels stretched by 1.25. I agree you gain on brightness but you might lose out on sharpness - although many on this forum seem to think that this sharpness is a bad thing.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 02-03-2012 10:28 PM                     1) OK Brad, we get it: you hate screens without masking. At least you've changed from "it reduces contrast" to "perceived by the human eyes as a lower contrast" which claims that even after the actual contrast difference was measured (with no difference - proving your old theory wrong), we nevertheless perceive less contrast... what reputable studies did you base this allegation on? 2) I haven't worked on (or even seen) a D-cinema system with an anamorphic adapter, but I've seen the lenses in brochures. Are digital scope movies made available in 2048x1090 anamorphic DCPs? no  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 02-03-2012 10:37 PM                     Yes Dave, I DO hate screens without masking. It is simply improper and for those that play by the book, against DCI spec. It is "digital done wrong". ALL ambient lighting (including screen reflected light) reduces contrast which affects the sharpness and color saturation. Pick the specific wording apart all you like, but the fact remains. Even John Pytlak has spoke of this in the past if you care to do your research. I first noticed it in the early 90s. I was working at a theater where the two large auditoriums had different curtains and masking, but were otherwise identical. I always noticed #4 had a significantly better looking image than #5. Since they were the same, I flipped lenses one night thinking it was the lens and wanted to prove my theory correct. Nope, the image that had the "pop" to it remained in #4. So then I tried opening the port windows thinking it was that. Nope again. I wrote it off to lamphouses/reflectors. A few years later new systems were installed there. Yet again magically even with different equipment, #4 looked noticeably better than #5! It wasn't the lamphouses or anything else, that AUDITORIUM was better. Must've been the screen surface, right? Nope, they both got new screens after that and AGAIN #4 looked noticeably better than #5! That's when I put more attention on the curtains since that was the only difference. You see #4 for whatever reason had all black curtains up front, where #5 had colored curtains right up to about a foot surrounding the screen. I wrote it off to the curtains and ambient light. My theory was proven correct a few years later when the auditoriums were re-done during a theater remodel. I had all of the auditoriums spec'd so the first 15-20 feet permitted nothing but black curtains. Once that was done, ALL of the auditoriums had that magic spectacular look! After that I did some testing just looking at images with the curtains open and with curved screens. The contrast simply wasn't there. Neither was the sharpness or color saturation. I used the term "perceived" because I didn't want some snooty person coming in and making a big stink about how they could measure that it didn't make a difference to try and enforce the fact that all that matters is what the human customers see with their own eyes. Also I have 2 systems using anamorphics. Yes they exist. No the files are not made "squeezed" like 35mm, but if you care to read what Victor and Steve posted above, you will find your answer.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 02-04-2012 02:36 AM                     ...as Victor mentions, (paraphrasing) " Image stretched to fit the chip.." ... just an elongated image and not squeezed.. Then, taking the "elongated" image, shooting it through the 1.25:1 anamorphic attachment to expand to a true 'scope image as the results. Okey, learning more....thx.  |  IP: Logged Justin Hamaker Film God Posts: 2253 From: Lakeport, CA USA Registered: Jan 2004 posted 02-04-2012 04:13 AM                        One point I would add about the masking is that it results in a clean lines and a sharp frame around the picture. Whether this results in any measurable change to the picture, I don't know. One way to illustrate this is comparing the difference between my indoor screens and the drive-in screen. Obviously the quality of the picture is different between the two, but it can be quite distracting how the flat picture does not fill the screen side to side at the drive-in. The effect is especially noticeable under a full moon when the sides are well lit. This is anecdotal, but it would tend to suggest the ambient light reflecting back from the unmasked portion of the screen does alter the perception of the image on the screen. We also get complaints at the drive-in from customers who think they are not seeing the full picture because it doesn't fill the screen side to side. The scope picture fits the screen almost perfectly side to side, and leaves a very narrow unlit portion at the top of the screen. While the flat picture fits perfectly top to bottom, it obviously leaves a white letter box effect on the sides. One interesting note since we went digital. In a couple cases we had to make the choice showing the full scope image and leaving some screen uncovered, or completely filling the screen and cropping the image. What I found is that because the digital picture has crisp edges, it doesn't seem to be distracting to have small amounts of the screen uncovered and unlit.  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 02-04-2012 08:13 AM                     Once again you're telling me what I see. Wrong, I don't. I don't see any difference in contrast with or without masking. The unlit screen doesn't bother me. In the unmasked rooms I work at, nobody has complained - some have asked about the "missing" picture but when informed that this is normal, there's no problem. Just like with trailers for the other format. A deeply curved screen will absolutely reduce contrast. The unlit part does not contribute to that, it just shows the black level achievable. That's the only thing anyone will see on the unlit screen: the "absolute black" for that screen. True full black in the image area will be brighter from the projector (film or D-cinema) because of light still projected in "black" image areas and from contrast loss in the lens. After reading a previous rant about this "problem" I measured actual image contrast "with" vs "without" masking. There is no measurable difference. So you dislike it. I dislike Celine Dion "music". I don't invent snake-oil theories to convince other people that they are wrong to like it.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-04-2012 08:37 AM                     A straight multiplication sort of scaling (it is always done in the projector for DCinema) is the simplest, least intrusive sort of scaling. The actual resolution is NOT increased, of course. The light efficiency is what is gained. One is throwing away 23% of their light to merely zoom the lens. Another benefit is that if once ceases to zoom the lens (and refocus) and instead uses the anamorphic, the stability of the focus and positioning is greatly increased. I've yet to find any of the systems that will hold their focus settings (or position) over the course of a month...the creep is so small (except with NEC on InVision lenses), that most don't notice the drift. Put up a good focus target (Barco has the best and it can be loaded onto any DLP projector) and you will really see how far off it becomes over time. Again, anamorphics only benefit those with movable side masking screens where scope is wider than flat. -Steve  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 02-04-2012 10:11 AM                       To Dave's point about Celine, I wonder how anyone can stand her. As to masking or not, I disagree. If nothing else, there is some light leakage and reflections within and around the lens which end up on the screen. Masking helps with this. The problem is not as bad as with film but it's there. There are situations where bare screen is unavoidable, but I don't think we should encourage no making.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 02-04-2012 11:06 AM                     Dave, I predicted this. You are the technician for and possibly also had a hand in designing a masking-less theater, so that means there is nothing wrong with it. It is clear now. "Nobody has complained". Clearly that means your theater did the job as best as possible and everything is just spectacular. After all "nobody has complained" should always be the benchmark for judging how well we all achieved a goal. Let's face it, people are stupid. We all know this. That's why you can simply tell them "its supposed to be that way" and they go back to the herd. Its simple (and cheaper). Bare unlit screen "doesn't bother you". I get where you are going with this. Clearly everyone else shouldn't be bothered with it either since you aren't. I guess since some people aren't bothered by people talking on their cell phone during a movie that means we shouldn't be bothered by it either...or does the "not bothered by" rule only apply to you? Might I recommend you leave your house lights up during the movie? After all why bother spending money on that dimmer? Lights wouldn't affect the contrast anyway. Masking in DCI spec is there for a reason. Just because one idiot somewhere designed an Xtreme screen auditorium wrong doesn't mean everybody else should.  |  IP: Logged Mike Blakesley Film God Posts: 12767 From: Forsyth, Montana Registered: Jun 99 posted 02-04-2012 03:44 PM                        The question of masking is something I struggled with when we went to digital. Our screen is 15x30 and wall to wall, is slightly curved, and has fixed masking. With our film system, we had cropped the scope picture so it fit the screen exactly. With digital, we decided to fit the whole picture onto the screen, which of course leaves about 15" un-lit at the top and bottom. It drives me nuts, and I agree the picture looks better when it's masked on all sides, but I really don't want to go back to cropping the picture again either. But, there's no way to install movable masking on our screen without ripping the whole front end out and redoing it (ask Gulbrandsen, he's seen it), so here we are. The fact that "nobody complains" does carry a little bit of weight when you have a decision to make. Usually, if an owner is paying attention he knows what must be done without having to hear complaints. But there are also compromises that need to be made based on the amount of money you have available. I would have loved to install movable masking (and a curtain!) when we put the digital in, but I have to make the business pay, too. I have a long "want list" of things I would like to improve, and movable masking and a stage curtain are definitely on that list.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 02-04-2012 04:24 PM                     ..unless you made your own moveable masking - course, it would be manual - with a roll of dubetene, 1/2" conduit pipe and a nylon pulley system for the upper masking, and just the conduit pipe and peg stops for the lower...  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 02-04-2012 04:27 PM                     Mike, have you considered moving the image in scope up to the top and bringing in something that sits in front of the screen to mask the bottom 30" off for scope movies? When we do installs, we setup the projector for the largest possible image on an empty screen, then we leave the target pattern up and have the masking guys mask to the target. The result is flawless aspect ratios, and the masking crews we have worked with appreciate having the "line" to go by, as it keeps their work straight and makes it a no-brainer.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-04-2012 04:59 PM                     Oh Mike...this is so easily solved...go into the screen file, increase the anamorphic ratio until the height is filled...sure people will be tall/skinny but they are used to F@$%@ed up images on their televisions so you'll get "no complaints", fill your screen and yet crop nothing!  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 02-04-2012 05:32 PM                        What if the screen masking gets both shorter _and_ wider for scope (vs. 1.85)? Is the anamorphic lens still a win for light output, or is it strictly for common-height screens? As for the "no masking" argument. I have two words: "exit signs." Given how badly designed most theatres are, do you really want the unused screen area to have a red glow (usually brighter on one side of the picture) during the movie? As a patron, this would drive me nuts (more so than overbright exit signs already do).  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 02-04-2012 05:42 PM                     The anamorphic benefit is directly corresponding to how much more screen area scope uses. If your theatre has both maskings and scope only gets a little bit bigger, then the light benefit will be proportionally less. The theoretical MAXIMUM benefit is 25-26% in light...actual practice shows it is closer to 23% (nothing is free in this world). This is a huge benefit in larger lamps and will go a long way to extending lamp life, improving brightness for scope, especially for 3D processes like Dolby. -Steve  |  IP: Logged

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