HDTV is a type of television signal, which is scheduled by government mandate to replace the current US standard, NTSC, by the year 2006. HDTV is different from NTSC in several ways. First, HDTV is broadcast in the 16:9 aspect ratio as compared NTSC's 4:3 aspect ratio. Second, HDTV resolutions are increased from (if expressed in computer resolution terms) 640 x 480 to either 1922 x 1080 (or 1080i) or 1280 x 720 (or 720p). Thirdly, because the signal itself is digital rather than analog, it can carry a lot of information, including full digital audio with multiple channels. In the section, How Projectors Interpret Formats there is a lot of information about how projectors map specific signals. The most important piece of information that relates to HDTV is that you should not buy an SVGA resolution projector if you want to watch HDTV quality signals. An SVGA will actually give you about the same resolution as a regular NTSC TV set because of issues with mapping the image. However, an XGA resolution projector will more closely match the HDTV signal, making for an image far better than an NTSC set. If you plan to watch a lot of television on your DLP® projector, you need to be aware of two issues. One. You must have a tuner to receive HDTV signals. Your projector does not come with a built-in tuner like a regular TV set does. You can get a digital box from your local cable company or from Direct TV. Just make sure the tuner can output an HDTV quality signal, and that the projector has the proper input. Two. If you want to watch TV using your DLP® projector, be sure to have an additional lamp. Projector lamps can last anywhere from 1000-4000 hours, and are not cheap to replace. Typically a replacement lamp will sell for about $400. You may want to consider a DLP® projector with a longer lamp life when you purchase. Many DLP® projectors today have economy modes which extend the lamp life by slightly reducing the brightness of the projected image. Recent News in Digital TV DTV recently made a big jump forward. The FCC has agreed on the way that DTV signals will be broadcast. There was some debate about what kind of broadcast signal to use, but it has been decided that 8VSB will be the type of signal used for broadcasting DTV. What this means to you: Better TV Sooner. The decision makes it easier for broadcasters to build out and produce more DTV programs. They no longer have to fear that their investment will be wasted on modulation standards which could have become obsolete. Clear Choice of Which Set-Top Box to Buy. As a consumer you were also given the choice of which type of receiver to purchase. Now you can purchase a set-top box and feel entirely confident that an 8VSB box will be able to bring you DTV in the near future. Greater Product Selection. With the controversy settled, there are likely to be more manufacturers that are willing to throw their products into the ring, including TVs with built-in DTV tuners. That means more choices, and hopefully lower prices. More Advanced Topics: Deciphering Cables and Connections » Interlaced and Progressive Scan Signals » Improving Picture Quality with Line Doublers and Scalers » You are here: HDTV Standards 3:2 Pulldown, the Film to Video Process » Video Calibration »     Source code: