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Projectors

Advantages and Limitations

Projectors are sometimes called "front projectors" or "two-piece projection systems" in reference to the fact that a projector is typically used with a separate screen that is either mounted on a wall or hung from a ceiling. However, these days many users of the more inexpensive projectors simply shine the picture on a white wall to save the cost of the screen.

Advantages

Largest possible picture. Front projectors generate the biggest possible image size. You can use them to create the very large screen experience of a commercial movie theater in your own home. In theory, actual image size can go up to 300" diagonal or more. But in reality the size of any given projector's image is limited by its light output. Nevertheless, most projectors produce beautiful images at sizes of 90" to 120" diagonal, which is far larger than anything you can get with flatscreen TVs or rear-projection TVs.

Smaller images a great option also. Perhaps you don't want a huge image, or maybe you don't have space for one. If this is the case, a projector can be used to throw a smaller image, say about 60" diagonal. So it can serve as an inexpensive substitute for a 60" plasma TV. At this image size the picture is usually very bright, and can be used with some of the room lights on. Given the low cost of many entry level projectors, this can be the least expensive way to get a 60" picture on your wall.

Low cost. Believe it or not, a front projector can be the least expensive alternative for big screen video in your home. Some projectors built for dedicated home theater have now dropped below $1,000, making them much less expensive than flatscreen TVs or rear-projection TVs. They can even be cheaper than a regular 36" television. Of course, projectors range in price from very cheap to very expensive depending on a variety of performance factors. But even some of the best ones are now mass market consumer products and much more affordable than they used to be. And measured on a cost per diagonal inch basis, they are clearly the least expensive video products on the market.

Space saving. A small projector that is mounted on a coffee table, a rear shelf or bookcase, or mounted on a ceiling, takes up no floorspace in the room. When not operating, it is largely invisible. Using a projector gets rid of the big box television that really doesn't look very good in the room when it is not being used.

Easy to install. The ease of installation can vary actually. But if you are setting up a simple system on a coffee table or a rear bookshelf and shining it onto a white wall, it really is as easy to set up as a simple television. They are lightweight, and one person can pull it out of the box, hook it up and get a picture on the wall with little trouble. Sometimes some adjustments are required to fine tune the picture so that it looks its best, but that is true of all video products including conventional televisions.

Limitations

Dark room often required. Front projectors look their best in a darkened room, just like a movie theater. When you view in a dark room you get maximum contrast and sparkle in the picture. Whether you need a dark room or not depends in part on how bright your projector is, and in part on how picky you are about maintaining maximum image quality. If you are trying to create the "movie theater" experience, this is not really a disadvantage since you want a dark room anyway. However, if you plan to have a lot of family or social gatherings around your screen, a darkened room may not be desired. So your intended usage needs to be considered before selecting a front projector.

Maintenance required. Most projectors require maintenance attention that flatscreen and regular televisions do not. All projectors operate on lamps that need to be replaced periodically, and lamps can cost $300 to $400, or even more in some cases. The frequency of lamp replacement depends on the model and on your usage, but many projector users replace lamps every two to three years.

In addition to lamp replacement, most projectors have air filters that need to be cleaned or replaced every couple of months. Failure to keep filters clean can reduce lamp life and increase the chances of dust getting into the unit and creating fuzzy spots on the projected image. Once this happens, a projector usually must be returned to the dealer or manufacturer for cleaning. Some projectors have sealed optics that eliminate this issue, but most do not since sealing the optics adds cost to the unit.

Installation can be more involved. As noted above, the ease of installation varies based upon how you want to set it up. If you plan to ceiling mount it, you may need to hire some help to run power and signal cables through the walls. Furthermore, if you are using a projection screen as well, then hooking a fixed screen to the wall, or installing an electric retractable screen on or in the ceiling adds further steps to the installation process. If the projector does not have physical lens shift capability, the job of ceiling mounting to fit a screen must be done with particular care. ("Lens shift" is a feature that lets you move the lens up and down, and sometimes sideways, in order to adjust the location of the projected image without moving the projector. Most projectors do not have this feature, and some do.)

Rainbow artifacts. In choosing a projector you should be aware that some users of projectors using DLP technology can see color separation artifacts, commonly known as rainbows, or rainbow artifacts. This is an unfortunate side-effect of the spinning color wheel in the light engine of a DLP projector. Most people are not sensitive to this phenomenon, but those who are can experience it as anything from a minor distraction to a severe flaw that makes the projector unwatchable. In addition to being visually distracting, the effect is also reported to cause headaches and eyestrain. If you are acquiring a DLP projector for home use it is important to verify that you, your spouse, and any other regular viewers are not sensitive to DLP rainbow artifacts.

Texas Instrument, the maker of DLP technology, along with the vendors that build the products, have successfully addressed this problem by accelerating the rotation speed of the color wheel on models intended for home video use. A much smaller percentage of the population is sensitive to rainbows on DLP projectors with faster wheel speeds. The bottom line is this: the standard rotation speed on most DLP projectors is designated 2x. It is these units that cause the most complaints. DLP projectors with 4x or 5x wheels are much less problematic. Meanwhile, projectors using LCD or LCOS technology do not have the problem at all, since they have no color wheels in their light engines to begin with. Furthermore, the more expensive 3-chip DLP projectors have no problem either, since they don't use color wheels. This disadvantage is therefore limited to single-chip DLP projectors with standard 2x speed color wheels.

Separate audio system required. Most projectors either have no audio on board, or if they do, it is not audio you'd want to use for movie presentation. So most people who opt for a projector are also setting up a separate surround sound audio system to go with it. (Big pictures look better with big sound.) If budgeting the whole system is too much of a stretch, you can always get the projector today and use your current two-channel stereo as a good audio solution until you have the cash and time to get into the world of multi-channel surround sound.

In short, the projector solution is not as plug-and-play as a television. So if you are taking the step up to large screen projection, carefully think through what you will need to do to install it the way you want it.

Who should use a projector?

A projector can be used either for very large screen home theater, or as a less expensive substitute for a big-screen TV. You determine how big you want the image to be based on how close to the wall or screen you place the projector. But typically you would not bother to go smaller than about 50" diagonal. Unless you have a very bright projector, ambient room light will adversely affect the quality of the video image by making it look dull and washed out. So those with a lot of ambient light should either think about projectors with high light output, or focus on the alternative video products linked below.

A big part of the decision depends on what you intend to do with it. If the screening of widescreen movies is your primary interest, projectors do this in a much bigger format than any other solution. But if you plan to watch a lot of television and news, though you can do this on a projector, most people find that flatscreens or RPTVs or even tube televisions are the better answer. Be mindful of lamp replacements costs--if you like to run your TV most of the day as background noise, you will not want to use a projector in this manner.

Also keep in mind this important trade-off: the projector will give you the largest image possible, or it can give you a very inexpensive 50" image. But either way it often requires periodic cleaning of air filters and occasional lamp changes that none of the other video products require you to bother with. There are a few projectors available that have no filters and no filter maintenance, and they can have extended lamp life as well. So this maintenance issue can be insignificant if you select one of these units. However, most projectors will require periodic attention.

Of course, if you are going for the big multi-channel surround sound system and the full "theater" audio experience, it is best to have a very big video image to match it. There is something just not right about having a room-shaking surround sound system and a relatively small 40" to 60" picture sitting in the middle of it. You get the feeling that the audio is fully-charged but the video needs some help. So if the true movie theater experience is your main goal, find a way to cut the lights and go for the large screen front projector.

Flatscreen TVs-Advantages and limitations
(includes both Plasma and LCD TVs)

Rear-projection TVs-Advantages and limitations

Direct-view CRT-Advantages and limitations

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