Sunday, April 30, 2006
TV transmitted in high definition format offers the best picture possible. This is due, in part, to the resolution in which the video image is transmitted. HDTV is broadcast in resolutions of 720p, 1080p or 1080i. 1080i is the most prevalent HD format, because it seems to offer the best image. It is currently being used by several major networks for the transmission of HD, including PBS, NBC , CBS, Showtime, and HBO. Another special feature of HDTV is that it‚Äôs broadcast in widescreen format, with an aspect ratio of 16:9, which is analogous to the screens found in movie theaters. These capabilities add up to a dramatically improved picture for viewers.
Viewers who want to watch HDTV have a number of options. Set-top components make it possible for older model TVs to pick up HDTV. These components convert the HD signal to an analog signal for broadcast. The resolution won‚Äôt be as good, however, and widescreen formatting will appear in letterbox mode on the set. Many new sets have HDTV tuners pre-installed. These are known as integrated HDTVs.
Viewers who have HDTVs should talk to their TV service providers about getting a receiver that will allow them to pick up the HD signal. An over-the-air antenna is another option for picking up HDTV, especially local channels. Right now, local networks are not easily accessible in HD via most TV subscription services. With an over-the-air HD antenna, however, it‚Äôs possible to pick up local broadcasts for free, without going through a TV service. HDTV can also be accessed on some sets via a cable card connection. This connection allows the TV to pick up cable channels and HDTV channels. Viewers who buy new HDTVs should know that they will still be able to watch standard TV, because most HDTV models have analog format capabilities.
High definition transmission is not exactly affordable for the average TV network, so it‚Äôs likely that only a select few channels will be offered in HD. This is the case now, as most TV subscription services offer special packages of HD channels -- usually the most popular networks, like HBO and ESPN. In fact, only a few channels in the United States are offered in HD format, including Disovery, NBC, ABC, FOX, PBS, Encore, Cinemax, Starz, Showtime, and The Movie Channel. Right now, HDTV is being broadcast over 1200 TV networks, in addition to most cable networks.