One of the big questions you face when planning a new home theater is whether to get a rear-projection TV (RPTV), or a two-piece system consisting of a front projector and screen. If you are at this point in the planning process, read on. As you will see, both approaches have benefits and limitations.
The appeal of Rear-Projection TV
There certainly is a great deal of consumer appeal for RPTVs these days. And it's easy to understand. Part of it is due to the simplicity of the product. After all, what could be easier than getting a bigger TV? If you want a larger image with no muss and fuss, it can be ordered at any local big-screen retailer and delivered within a day or two. As long as you've got the space, you are in business with almost no effort.
Also, part of the appeal of RPTVs is the impression created by big-screen retailers that RPTVs are cheaper than front projection systems. While that may be true in the retail store, it is not true on the Internet as we will discuss momentarily. We will see that at most given budget levels, front projectors will deliver a much more cinema-like experience for the money.
Clearly there is a market for both types of home theater solutions. From a practical perspective your room size has a lot to do with determining which approach is best for you. If you don't have a large viewing room, a 40" to 60" diagonal TV will probably be plenty. In this case, the rear-projection solution is more practical assuming you can fit the box into the space.
But if you want the large screen cinema experience and your room size will allow it, front projection is the way to go. Front projectors are made to produce screen images in the range of 70" to 120" diagonal or more. Once people realize they can get a picture up to four times the size for the same money as a good RPTV, it opens up a whole new world of entertainment possibilities.
So let's take a closer look at the advantages and limitations of RPTVs vs. projectors. Hopefully we can help you make the best choice for your particular situation.
Rear-Projection TVs: the Good and the Bad
As noted above, the advantages of RPTVs are obvious. There is a wide array of products in different sizes and price ranges. There are numerous local showrooms. And they are simple to buy and install.
However, RPTVs have several limitations that front-projection systems do not. Among them are limited screen size, poor viewing angles, excessive reflections if you use screen savers, poor aspect ratio management, and poor use of floorspace.
Screen size. An obvious difference to be sure, but worth thinking about for a moment. A 100" diagonal front projection screen is four times the surface area of a 50" RPTV. If you want to put real "theater" in your home theater, the projector and movie screen approach delivers it. RPTVs are just big televisions.
Viewing angles. On your next trip to your local big screen retailer, take particular notice that many RPTVs have a rather small "sweet spot" from which they can be optimally viewed. To demonstrate this to yourself, assume a viewing position directly in front of and eye-level with the unit. Then move away from that spot and watch how color, contrast, and brightness degrade the farther you get from the sweet spot. Some products are worse than others in this regard. But if you are shopping for an RPTV, keep this in mind. On many products the viewing angle can limit the number of people who can watch the set enjoyably.
With a projector and screen system, the screen is both larger and much easier to view from a wider angle. When using a high quality theater-grade screen, color, contrast, and brightness do not shift much as you move around the room viewing the picture from different locations.
Reflections. The showroom floor of your big screen retailer is a great place to get a demonstration of the reflection problem. If there is any ambient light in the room, objects in the room (including you) will be reflected in the screen. If there is any direct light source at a complementary angle to your viewing angle, you will see that light source glaring in the screen also.
Reflections create a serious degradation of picture quality. Fortunately they are usually caused by screen-savers-clear protective material that covers the fragile screen itself. The screen-saver can be removed on most RPTVs. On some it is easy; but on others it is a major project requiring the removal of the front frame.
If you plan on buying an RPTV and you want to eliminate the reflection problem, check to see if the dealer will remove the screen-saver and if there is an extra charge for doing so on the model you want. Remember however that the unprotected screen is fragile and very expensive to replace if damaged.
Front-projection systems do not have reflection problems so you don't need to worry about this issue when buying a projector and screen.
Poor use of floorspace. An RPTV is a large box that will stand out from the wall about three feet. So it shrinks the viewing space by three feet. It is also difficult to disguise when not in use. It is an appliance which dominates the room it is in.
With a projector and screen, the screen is usually mounted on the wall or ceiling mounted near a wall. Therefore it lets you use the full room depth for viewing. A wall mounted screen can be covered with a curtain when not in use, and a ceiling mounted electric screen can be retracted. So the projector and screen combination gives you more flexibility in terms of "making it disappear" when not in use, and it uses no floorspace. If you are setting up a dedicated theater room, this is not a concern. But if you are installing your theater system in a multi-purpose room it may be an important consideration.
Aspect ratios. A serious issue for any new video display system is aspect ratio management. Time was when every video source was 4:3, just like your television, and you didn't need to worry about this. But today video material comes in a variety of aspect ratios. So if you are designing your own home theater, it is important to give this issue careful thought. So let's look at the problem of aspect ratio management in some depth.
The aspect ratio of a video image is the ratio of its width to its height. Standard television screens are 4:3, which means they are four units wide for every three units of height. Another way to refer to the 4:3 format is the numeric value 1.33, which is 4 divided by 3. The picture can then be thought of as having 1.33 units of width for each unit of height.
All standard (non-HDTV) television broadcast material today is broadcast in 4:3. Most older classic movies like The Wizard of Oz, Gone with the Wind, Fantasia, and Casablanca were also filmed in 4:3. All of this source material is designed to fit perfectly on a 4:3 television screen.
However, most modern films are being produced in one of several widescreen formats. On the back of many DVDs you can find the movie's actual aspect ratio in the fine print. Instead of 1.33, you will often find other aspect ratios. One of the most common is 2.35. What that means is that for each unit of picture height, the picture will be 2.35 units in width.
Clearly, a movie with a 2.35 aspect ratio won't fit on a 4:3 (or 1.33) screen without some compromise. There are two ways to make this compromise. The first is to show the movie in its correct original aspect ratio. To do this, the television will present the image with black bars along the top and bottom of the image. This shows you the entire movie as it was filmed. However, the picture looks smaller because you are only using a portion of the television's 4:3 display area. Many people don't like this "shrunken image" effect.
The second possible compromise is to display the movie in "Pan and Scan". Some DVDs have this option and some don't. Pan and Scan refers to the editing of a movie to fit a 4:3 screen. When this is done only the "most important" portions of each frame are displayed, and the rest of the image is discarded. So you do not see the full image as it was originally filmed.
For example, imagine a scene in which two people are talking with each other across a table. The original film image would be wide enough to include both characters in the scene. But in Pan and Scan, typically either the person speaking or the person listening would be shown since the 4:3 format is not wide enough to show them both. So in the Pan and Scan format you give up image information. But the benefit is that what you do see, you can watch in full 4:3 screen format without black bars.
HDTV's 16:9 format. There is now another aspect ratio to deal with that complicates things further. The new HDTV format is 16:9, or 1.78. Some of the new RPTVs on the market have the wider 16:9 formats rather than the standard 4:3.
This complicates the problem of aspect ratio management. For even though the new 16:9 TVs are compatible with whatever HDTV programming might be available, the aspect ratio is incompatible with 4:3 video sources. It is also incompatible with most movies which are being produced in aspect ratios wider than 16:9. That means that the 16:9 RPTVs are incompatible with the vast majority of video source material on the market today.
16:9 RPTV compromises
Several compromises are being made to fit non-16:9 material into 16:9 RPTVs. First, 4:3 material can be displayed in native format with gray bars on each side. Manufacturers are now making these bars gray rather than black to avoid uneven burn-in. While this is good for the set it degrades the viewing experience since image contrast and color look best when the image is presented in a black frame. And once again you have the shrunken image effect-the use of only a portion of the screen is fundamentally irritating.
That being the case, few people want to watch 4:3 material on a 16:9 set with gray bars on each side. So manufacturers have come up with an alternative-stretch the 4:3 picture sideways to fill the 16:9 frame. This distortion makes people look fatter. Round objects such as the turning globe at the opening of Casablanca look egg-shaped. This may sound ludicrous at first, but in fact many big screen retailers will demonstrate a 16:9 RPTV with stretched 4:3 video because, as bad as it is, most consumers prefer this distortion to seeing gray bars and the "shrunken" picture.
Since neither of these options is very good, the 16:9 RPTV will offer other options for 4:3 display. You can usually zoom the picture up to where it fills the screen from side to side, but the top and bottom portions of the image are cut off. Sometimes the center portion of the 4:3 image is displayed correctly and the sides are stretched or the top/bottom portions of the image are compressed.
The sales rep at the retailer can show you each of these operating modes, but you usually need to request it. If you are thinking of buying a 16:9 RPTV, you need to see the 4:3 display modes demonstrated to determine which of them is least irritating to you. Because that is what you will be living with when you watch standard broadcast television, music videos, and classic movies made in 4:3.
Meanwhile, not only does 4:3 material not display well on a 16:9 TV, a typical 2.35 aspect ratio movie (though it is "widescreen") doesn't fit either. Movies in the 2.35 ratio will be displayed on a 16:9 set with black bars at the top and bottom-it's the same effect of the "shrunken image" that you get on your current 4:3 TV, but the bars are not quite as large. (The top and bottom bars are black instead of gray in this case because that's the signal coming from the source.)
Keep all of this in mind when you go into the big screen retailer. And be aware that the demo material in many of these stores is either HDTV broadcast or canned 16:9 format demo discs. These demos will not show any gray or black bars-just pristine full screen video. This demo material is not representative of the mix of video sources you will be viewing at home.
So ... 4:3 or 16:9?
Since you can get RPTVs in both 4:3 and 16:9 format, if you are going the RPTV route you need then to decide which format is going to be the best for your overall usage. The advantage to the 4:3 format is that all of the current standard broadcast material will fit that format without compromising the image-no gray bars and no distortions to fit the screen. The disadvantage of the 4:3 format is that 16:9 material will be shown with black bars whereas on a 16:9 set it is displayed full screen. And all movies that are wider than 16:9 will be shown with black bars that are 1/3 larger than the black bars you will see on a 16:9 set.
On the other hand, a 16:9 format RPTV cannot display 4:3 material without gray bars or distortion, nor can it display most widescreen movies without black bars top and bottom. The only material that fits comfortably onto a 16:9 set is (a) HDTV programming and (b) the relatively few movies done in the 1.85 aspect ratio, which is close enough to 1.78 that it looks full screen. Bottom line: regardless of whether you get a 4:3 or 16:9 RPTV, their fixed aspect ratios will always require compromises in viewing quality.
Projectors offer flexible aspect ratio management
Whereas RPTVs are inefficient when it comes to dealing with variable aspect ratios, the use of a projector and screen gives you much more control. That is because screens can be installed with electrically driven masking systems. For the ultimate in home theater quality, this is the only way to go.
Masking systems are black overlays that open and close to fit the actual image being projected. So no matter if you are projecting material that is 1.33, 1.78, 1.85, 2.35, or whatever, the masks can be set to create a perfect black frame around the projected image. With this type of system there are never any gray bars on the sides or black bars top and bottom-just the pure image in a solid black frame. This gives you the best overall visual presentation, and the maximum flexibility in handling all aspect ratios on the market.
But aren't RPTVs cheaper than projectors?
There are some very cheap analog RPTVs, no doubt about it. But if you are reading this article on ProjectorCentral.com, we assume you are interested in the higher quality digital systems available today. And if you are thinking in terms of a digital RPTV that is 480p and HDTV compatible, then you are also in the ballpark, price-wise, for a front projection system as well.
For example, at this writing you can get an excellent 55", 16:9 format Mitsubishi HD1080 for about $3,500. However, you can also get an HDTV-compatible InFocus LP340 with a 100" diagonal fixed screen for about the same money. Now if you wanted a screen with full electric masking capability it would be somewhat more. But for the money invested the LP340 will produce more dramatic theater-like results than the RPTV simply due to image size.
The Pioneer Elite Pro710 is a 64" digital RPTV selling (at this writing) for about $7,500. For the same investment you can get instead an NEC LT155 HDTV-compatible projector with a top quality 100" screen including the full electric masking system. Such a set-up will produce a truly stunning video display compared to that offered by the Pioneer.
There is a genuine market for both RPTVs and projectors for home theater. RPTVs are simple, but they have limitations in screen size and performance. Projectors and screens require some installation work, but once it is done you end up with a more dramatic theater experience.
The bottom line is this: if you are looking at digital RPTVs and your viewing room can accommodate a 90" or 100" screen, don't overlook the possibility of a projector and screen instead. If you can afford a digital RPTV, you can afford a projector. And dollar for dollar the projector will often deliver the maximum "wow" factor for the money invested.