Angles Of View
Vol. VI, ©Da-Lite Screen Company September 2000
Home Theater - The Big PictureThe reason all of us enjoy going to the movies is that in some often unconscious way we are transported into other worlds where, for two hours or so, we are encouraged to share and experience loves, lives, adventures, and characters that are otherwise extraneous to ourselves. The cinematic techniques which comprise this experience are as numerous and varied as the degree to which their results are successful. However, whenever the purpose of the finished product is our entertainment, it will depend greatly on the convolution of two fundamental attributes: illusion and immersion. The accomplishment of the first, of course, generally determines the extent of the second.
Developing these concepts of illusion and immersion so that they acquire particular focus, we can see that whatever success they may have as a result of the software seeking to stimulate them (the movie) can be grossly undermined if not destroyed by the environment of their presentation. Beginning to watch a film in a theater where the management has forgotten to extinguish the house lights is an experience no one finds satisfactory. Neither do we appreciate for very long listening to a suddenly silenced soundtrack.
To state these conditions positively, when we go to the movies, we expect to view the projected software in zero ambient light and to have its images in focus and its soundtrack in synch. Many of the other attributes of the visual display are, if not exactly ignored, typically taken for granted. Even we in the A/V industry are not likely to comment on the resolution or contrast of a film that we have just seen. Nor are we able to say anything qualitative about the color values that informed its various scenes.
True, we might as readily appreciate its photography and the content of its soundtrack as we simultaneously appraise its acting and its plotline, but none of these has anything whatsoever to do with a film's presentation. If the projection lamp is bright enough and if the print being shown is in synch and unscratched, if the sound system is adequately amplifying and properly "playing" the soundtrack, and if the house lights are sufficiently low, then the presentation may be termed effectual. Presentation values improve, then, in precisely inverse proportion to the degree to which we notice them.
Now, what about when we seek to take the experience we have enjoyed so many times at the movies home with us? What will it take to enable us to go to the movies without, as it were, going to the movies?
Broadcast television has for years been beaming movie programming through our sets and, thus, into our homes. No one, however, was ever tempted to confuse what she was watching on whatever "...Night at the Movies" with the real thing. If we worked very hard at ignoring the increasing frequency of intrusively interruptive commercials, we might be able to muster some slight feelings of illusion, but immersion from, at least, a 19-inch television set and its single, tinny speaker was never even a possibility.
That was the first medium through which movies were seen at home. The second, of course, was the VCR which, while not much better looking than TV, at least got rid of the commercials and thereby increased the illusion factor by restoring to the movie being watched its original continuity. Nevertheless, even though the diagonal of its tube might have increased to 27 inches, we were still watching a TV set.
The advent of 3-gun CRT video projectors enabled, for the first time, the conversion of a TV into a PTV (projection televison) and the age of the at-home big screen began. In their first iterations, PTVs had 67- inch diagonal screens and while by today's standards that's hardly huge, back then it was a non-trivial 500% bigger than its tube based predecessor. And if, once that device was set up in your living room or den, you didn't move your chair any farther back from where you were accustomed to watching your old TV, your home screen for the first time filled enough of your visual field to look actually "big." The trouble was even though the size of your picture had grown more closely to resemble the scale of the movies, that very enlargement allowed other, much less welcome artifacts to pop out of the picture and annoy you.
Five-hundred and twenty-five raster lines, for instance, get a whole lot easier to notice if they are scanning across a screen that's no longer 16 inches high but 40. NTSC television, with those 525 lines of resolution, required a viewing distance of about 10 screen heights if they were not to be discernable. If you sat before your new PTV at what was now only a distance of about four screen heights, those lines were, as it were, in your face.
One other obvious point is worth mentioning here. The aspect ratio of your PTV screen was still the TV- inspired (but hardly inspiring) 3:4 and few, if any of the movies then being made were shot in that antiquated aspect ratio. So you watched even on your new big screen imagery that was severely truncated from its original shape.
But then came laser discs and they did have resolutions higher than the TV signal and they were able to exhibit their source material in its original aspect ratio, albeit at the cost of cropping the top and bottom of your screen into various "letter boxed" rectangles. They also contained audio information which was capable of being distributed into a five- channel sound system which really was capable of surrounding you.
Maybe the picture you were watching still didn't really look like it would have in a movie theater, but it now began to do a pretty good imitation of sounding just as convincing as the movies themselves did. The helicopter did sound as though it were flying in from behind you from the left and then did sound as though it were thundering off in front of you to the right. So while hearing may not be believing, surround sound was a big boost both to illusion and immersion.
Nevertheless, we do not speak of going to "hear a movie." We speak of going to see one; so, of the two, the visual part of the experience will always dominate the audio. And if the reference standard for what we can reproduce at home is film itself, the bar we have to surpass is high indeed.
Film, of course, is an analog medium. This means that its resolution, its capacity to display very fine detail, is neither low nor fixed. It also means that there aren't any raster lines or pixels making up its images and that its dynamic range (the available differential between its brightest brights and its darkest blacks) can be very large. Regrettably, when film gets transferred to video a lot of these virtues can become significantly compromised.
Video, of course, is not an analog medium. Its resolutions are fixed and its raster lines countable. But also because it's not analog, video (or what we are here loosely calling video) can be manipulated electronically in some crafty and extremely helpful ways. There are black magic boxes which can multiply those raster lines such that they're harder to see and much harder to count.
For the whole host of new projectors which are not CRTs, the thresholds of brightness and resolution routinely being crossed are increasingly impressive. And, where once it was the CRT and only the CRT that had the ability to display accurately a wide range of resolutions, the deployment of the new magic boxes, the scalers, are permitting devices with fixed resolution to display quite commendable imagery whose own native resolution is other than theirs.
That being so, it doesn't take much percipience to predict the eventual disappearance of CRT projectors altogether from home entertainment environments. The DLP and LCD alternatives are already a whole lot brighter and, as their innate resolutions inexorably grow to XGA and beyond, the pictures that they project (scaled or otherwise) are looking, these days, extremely good.
So if you get yourself a dark room and you shine one of these new projectors at a good sized Da-Lite screen and you play a good quality DVD with a soundtrack that will envelop you through your five speakers and can rattle your breastbone through your sub-woofer, is there at last as much illusion and immersion in your home as you'd get from seeing the same movie in a theater?
The answer is, pretty close. For sure, you have to have bought high quality equipment and you have to have taken quite a lot of care with its setup. Even then, the quality of the audio portion of your experience is very much the more reliable. And it should be, as the physical properties of the sound waves issuing from your speakers need differ hardly at all from the sound waves generated by a real helicopter. Whether the levels of illusion and immersion are as adequate to convince your own visual system of a comparable reality depends, of course, on its particular pair of i's