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SELECTING A VIDEO PROJECTOR - A PICTURE IS WORTH A THOUSAND WORDS
LCD projectors provide a large screen visual display from video and computer feed sources. Picture RESOLUTION and BRIGHTNESS are the primary considerations when selecting an LCD projector for a particular screen size and application.
• Resolution is measured in pixels.
• Brightness is measured in lumens.
Computer displays need higher resolution and a higher pixel count than video only images. All our LCD projectors project standard NTSC domestic video with the horizontal scan ranging 500 to 800 lines. Use your VCR or video camera, any source that has a standard video output. If you are using a PC or MAC computer, select the LCD projector that will match your computer monitor graphics display (VGA, SVGA, XGVA, or MAC 13 to 21 inch monitors).
Larger screens require more brightness (lumens) than smaller screens. Other factors such as type of screen and ambient light also effect the quality of the projected image. Our general recommendation is to select a matte white screen, in the smallest size applicable for your viewing audience, with the highest lumen output LCD projector your budget will permit.
Today LCD Large Screen Projection Systems can be largely "plug-and-play" for the connections of the input and output devices. The selection and installation of the right screen and LCD projector takes some extra care. If you are looking for an LCD Large Screen Projection System give us a phone call today! We'll help you select components and installation essentials needed for the satisfying results you want. Phone for Special Church Pricing! 800-523-8195. Full Line of EIKI Projectors available!
Resolution measures the amount of detail that can be seen in an image. For computers, resolution is expressed in the number of pixels down and across the screen, and it's important that your projector is capable of matching the resolution of your computer system. VGA requires 640 x 480 resolution, S-VGA 800 x 600, XGA 1024 x 768. Standard 13" Macintosh monitors use 640 x 480 resolution, but to show a 17" Mac monitor full-screen requires 832 x 624. Engineering workstations can require even higher resolutions. For this reason, the resolutions of three-tube projection systems are normally expressed in scan rate ranges, to allow you to match them to the workstation or specialized graphics card you may use. For video, resolution is expressed as the number of lines per inch visible on a test pattern. The video resolution specification (which is not the same as the horizontal computer resolution and actually is determined more by the electronics of the projector than by the LCD panel) can serve as an overall indication of the video quality you can expect.
Brightness. As you start to compare LCD projectors, you'll need to know the brightness in ANSI lumens (the current ratings standard, and, please note, not comparable to "lumens" expressed in non-ANSI terms). As a rough guide, a rating of 600 - 800 ANSI lumens works well with a 100" to 150" diagonal screen with lights dimmed, but you'll want at least 1,000 ANSI lumens when you go to larger screens and 1,500 or more if you want to project in bright lighting conditions. Your best bet, of course, is to ask your sales rep to demo the LCD projector under conditions typical to what you'll see.
Size and Weight. There's often a trade off between small size and image quality. If you depend on a sales force to voluntarily take your projector and program from call to call, you may find an ultra-compact LCD is your best bet, as an expensive multimedia production does no good sitting in a closet or a car trunk. Others may find, however, that a 12 to 15 pound LCD projector offers a better combination of brightness and price, yet is still very portable. Naturally, if you're going to put the projector on a cart or a ceiling mount, size is much less important.
Your Video Source. Do you need to show S-video or just standard composite video? Will you take the unit overseas (and thus need the ability to accept PAL or SECAM signals and overseas power)? What's the resolution of the video? Projectors that produce higher video resolutions produce sharper, cleaner images. New digital video systems are here, and many projectors now include component video inputs to allow direct connection to DVD players, plus digital TV tuners and VCRs when they are available. It's important to note that any projector, monitor or TV will be able to display digital TV signals. If you want to take advantage of the HDTV clarity, however, you'll need a higher-resolution video or computer projector, and a component input will help by reducing noise. (It works by dividing the chrominance portion of the video into red, green and blue segments.).
Aspect Ratio is becoming important with digital TV formats as well, and it's important that your projector will display the aspect ratio of your source. Most computer and video images use a 4:3 ratio that is, the ratio of the width of the image to its height is 4:3. But wide screen movies and HDTV formats use 16:9 and SXGA, while it will display on a 4:3 monitor, actually uses a 5:4 ratio.
Lamp Type. Most LCD projectors use a metal halide or UHP source, which offer a very white light and a useful life of 750 - 2,000 hours (depending on your projector model). They typically do not burn out suddenly, but gradually grow dimmer, giving you plenty of warning that it's time for a replacement.
Contrast Ratio, which measures the difference between the brightest white and darkest black your projector can produce, should be an important spec, but there seems to be a problem in how it's measured. We've done side by side comparisons between LCD projectors rated at 100:1 and 300:1 and found little or no difference in their images.
Color Spectrum. The number of colors you need, while once important, is no longer an issue. All of the DLP and LCD projectors handle 16.7 million colors.
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