Projection Screen

Screen projectors
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Screen projectors
Screen projectors
Screen projectors

Screen projectors



Screen Projectors: Features to Look For

Screen projectors are popular TV technology choices. Whether you choose a traditional CRT or high-tech plasma TV, there are some factors you need to consider when making a choice among the types of screen projectors available. This article contains some information to help you make an informed decision when shopping for screen projectors.

All screen projectors have several features in common: aspect ratio, resolution, brightness and contrast. Before choosing amongst screen projectors' technologies like CRT, DLP, LCD or plasma, you need to make several decisions regarding the general features you want your new TV to have.

Cost, of course is a major factor. With some screen projectors priced at over $2000, its important to recognize that there is a trade-off between screen projectors' price and features. Also, don't forget to investigate installation costs, if any. If there are installation constraints, it's a good idea to choose from among screen projectors that have zoom lenses and lens shifts. A zoom lens allows a variable distance between the projector and the screen. Lens shift lets you move the lens while keeping the projector stationary so you can adjust the image on the screen up, down, left or right as needed.

Once these basic installation issues are resolved, you can start looking at features like contrast, brightness, resolution and aspect ratio. To define contrast, try thinking of the brightest white and the darkest black you can. Contract is the difference in brightness between them. Some regard contrast as the single most important feature of screen projectors. In fact, images on screen projectors with excellent contrast can sometimes appear to be almost three-dimensional. Contrast also contributes to color saturation: the better the contrast, the more rich and vibrant colors will appear. You'll find one of two types on contrast on screen projectors: On/Off and ANSI. On/Off contrast is the ratio of the whitest white and blackest black that screen projectors can produce. ANSI contrast means that a black-and-white checkerboard pattern is used to determine the ratio. An ANSI contrast specification is more accurate.

Brightness is the measure of the light intensity of screen projectors and is measured in two ways: ANSI lumen rating and foot-Lamberts (fL). The ANSI method measures only the light-emitting capability of the projector. The foot-Lamberts method measures the light that the projector reflects back to the viewer and is considered superior. When setting up screen projectors, many people choose movie-theater type lighting where the room is darkened and the only light comes from the screen itself. Sometimes this is tricky, because a too-bright screen can cause eye fatigue. You need to figure out the luminance level for the projected images. Luckily, it's easy: just divide the ANSI-lumens from your projector's spec sheet by the square footage of your screen and multiply by your projector's gain. Luminance should be 12 to 24 feet in a dark room and 30 to 50 feet in a room with low ambient light.

Resolution is a measurement of the number of pixels from top to bottom and from side to side. The greater the resolution, the better the picture. So a resolution of 1920 x 1080 is better and one of 1280 x 740. Resolution is especially important when dealing with HDTV signals because its pixels are smaller. A screen projector should be capable of converting the signals it receives into its default resolution. This is called scaling.

Aspect ratio is the relationship between the screen's width when compared to its height. Here are a couple of examples from www.dtv.gov: A 32-inch diagonal traditional television screen is 25-1/2 inches wide and 19 inches tall. Widescreen aspect ratio is 16x9. A 32-inch diagonal widescreen television screen would be 28 inches wide and 19 inches tall. You may have noticed that older TVs (and computer monitors as well) are more or less square. Current TVs are set up to receive HDTV programming whose aspect ratio is 78% wider than it is tall. (Adapted from http://www.dtv.gov/).

The most important thing to remember when choosing from amongst the various types of screen projectors is that the features discussed in this article remain constant regardless of the brand or model you're considering. Whether you're looking at CRT, DLP, LCD or plasma, don't forget to compare features like contrast, brightness, resolution and aspect ratio to make sure you get the TV that's just right for you.




Screen projectors
Screen projectors Screen projectors Screen projectors
Screen projectors