A front projection home theater system uses a projector that projects the video image on a surface in front, thus the name. There are a few things to consider:

• What type of projector?
• What type of projector placement?
• What type of projection surface?

Type of projector

The projector can use many different technologies. Here are the most common:

• LCD

Most LCD projectors use 3 LCD displays, one for each base color (Red, Green and blue). They usually offer better color separation and depth. On the other side, they used to be less efficient in terms of contrast and black levels (the ability to provide more light intensity levels. The more levels possible, the better the contrast and black level controls). This is less true these days as the LCD technology has very well caught up on other technologies such as DLP. LCD display arrays typically have a larger separation requirement between each pixel. This causes what is called the "screen door" effect. This was especially true with older low resolution (640x480 and 800x600) LCD projectors. Nowadays, LCD projector use resolution of 1024x780 and more such that the screen door effect is much less a concern.

• DLP

DLP projectors have long been favorites for the more demanding home theater enthusiasts as it provides very deep black levels and contrast ratios typically over 1:2000. DLP technology also allows very bright images with typical optical power output over 2000 lumens. The main drawback of DLP technology is that it must use a color wheel in order to produce a color image. The color wheel is divided as a pie chart with each section letting a given color pass through using a color filter. As the motorized wheel turns in front of the light beam, it filters for red, green and blue. Older models had slower rotating wheels that caused what is called the "rainbow effect". The rainbow effect is seen by many people as an apparent colored separation and flicker in the image on the screen. It is more apparent as the user rapidly moves his eyes to look at different zones of a large screen. This is due to the fact that the DLP projector is never showing a full colored image in effect. It is rather displaying successive red, green and blue images at rates over 180 images per second. Nowadays, color wheels used in DLP projector are typically revolving at rates of 5 and 7x which makes it virtually impossible to see any rainbow effect. Another more advanced and technical aspect of DLP projectors is that they can be used to build stereoscopic projection systems since they do not polarize the light.

There is a second category of DLP projectors for the high-end market which have three LDP display elements, one for each of the three primary colors. This completely removes the need of color wheels and thus provides a true color output that is not exhibiting any rainbow effect.

• LCoS

The LCoS technology is one of the newest in the field of video projection. The main advantage of this technology is the possibility to create higher density arrays of pixel elements over LCD or DLP devices. This allows to create very high resolution display units and is thus well suited for high definition television applications. It is not yet as widely used in home theater projectors as LCD or DLP technologies.

• CRT

CRT tubes projectors used to be the reference in term of high-end home theater projection. They are still the best in term of raw image quality as the image is made from a scanning beam instead of digital pixel elements. This provides the CRT with a clear advantage to produce smoother while sharp images. CRT have been said to produce the most cinema theater-like experience as far as the image is concerned. They are less and less used in practice due to many factors. They are heavy, take much more space and require costly maintenance. Their CRT tubes wear over time and can be damaged by prolonged static image displaying. This is what is called a burn-in. Burn-ins are irreversible as they are caused by a deterioration of the phosphor pigment, thus the name as it relates to the phosphor being burnt literally. CRT projectors are also technically much harder to setup as they require convergence. Converging a projector relates to the manual (or automatic in more costly models) alignment of the three tubes images. This process may have to be repeated over time over a few months of use and is dependent on the amount of drift that the projector unit exhibit.

Type of projector placement

• Ceiling mounted

Ceiling mount is the best option if you consider a long term home theater installation. It will provide a cleaner installation by putting the projector out of the way and making it less visible with proper mounting. It is even possible to partially hide it in a box as long as you keep in mind that the ventilation is critical for proper operation of the projector. Ceil mounting a projector requires some planning regarding the distance from the projection surface or screen. Pay a close attention on the manufacturer specifications regarding throw distance ranges and make sure you can actually attach your projector to the ceiling at the proper distance before you buy. Most projectors provide a manual zoom lens. On some models, it is motorized so that you can change it from the remote control once it is ceil-mounted. The other factor to consider will be the height of your ceiling regarding the projection area. If you place your projector such that a high level of keystone correction is required, you will lose resolution and image quality in the end. Key stoning is a process by witch you deform the projected image from a perfect square to an image that has a larger bottom or top side such that it will end-up looking square on your projection surface, even if it is projected with an angle from your projector.

• Shelve or table mounted

If you are unsure about how long you will use a given home theater configuration, placing the projector in a shelve on the back of your home theater room or a table beside your sofa can be a suitable solution. Pay a close attention to well dissimulate the various cables in that case to avoid any tripping over them by people walking by.

Type of projection surface

In general, it is recommended to put a great deal of attention on the screen portion of your home theater. Many too often neglect that aspect in favor of buying a better projector unit. This is not necessarily going to give you the best image. It is like buying a fast sport car with a powerful engine and putting 4 season tires on it... Not the best handling and driving experience probably. Said differently, the projector and the screen you project on are two components that make a whole. If they are misbalanced, you will not exploit the full potential of any of these two components.

There are basically two types of projection surfaces:

• A wall

Here again it is a question of how permanent you plan on making your home theater setup. Initially, it could be a good idea to use a large wall as you start your new home theater room. This allows you to test things and make adjustments before buying expensive material. This being said, it will require at minimum to paint a large area of that wall with a wisely selected paint color.  Your paint should be white or slightly gray. You should also avoid too glossy paints. For a more permanent setup, you can buy specialized paints that recreate the proprieties of professional screen mats. This being said, don't expect the same level of quality that a professional screen mat will provide.

• A screen mat

This is the best way to go. Even if you think putting 200 to 500 dollars on a good screen is too costly, think of it as a long term investment. You will probably change 5 times your projector in the life time of your screen. With this in mind, you should be even more cautious when buying the screen then your projector unit... you want to keep it for a long long time.

There are many types of screen surfaces to discuss. The screen has many parameters to look for such as:

• Size
• Aspect ratio
• Gain
  • Screen gain varies from 1.0 to over 2.5. A gain of 1 means that the screen is not boosting the light it receives from the projector and diffuses the light evenly in all direction. In fact, think of the gain as the directionality level of a screen. As you raise the screen gain, it will reflect the light more directly toward the user's standing directly in front of the screen and much less for those who are standing on the sides or periphery. Why should you care about screen gain? In the past, projectors were much less bright and thus, we had to use higher gain screens to get a vibrant colored image on the screen, especially in rooms where some level of ambient light remained present. Today, with projectors having light output power over 2000 lumens, this is much less a concern. It is recommended in our opinion to go with a lower as possible gain screen, based on your room ambient lighting. We will cover this in another section in more details.
• Color tint
  • White
    • Usually a bit more affordable than gray screens. They can offer a pretty good image for the price.
  • Gray
    • Gray screens are said to better reproduce deep black levels and offer better contrast. Gray screens are also required in the case of stereoscopic projection applications as they preserve the polarization of light.