This week, well talk about digital and High-Definition TV, and what these technologies offer us. First, lets talk a little about how regular TV works. Traditional TVs display an image on your screen by painting the picture one line at a time until all 480 lines are on the screen. These 480 lines are drawn in an alternating fashion, know as interlacing. This means that all the odd numbered lines are drawn so that exactly half the picture on the TV is displayed, then the even numbered lines are drawn in, giving you the whole picture. After one image is completely drawn, the whole process starts again. This happens 60 times per second, giving us the illusion of motion. Interlacing allows our eyes to see the image as a whole otherwise we might actually see the TV image being drawn top to bottom. Since standard TV only shows us 480 lines drawn on the screen, the larger the TV screen the less crisp the picture. To see what I mean, the next time you are at an electronics store compare the same show on a 19" TV and a 36". See those lines that are visible in the 36" screen? Those are the TV scan lines, 480 in total. All standard analog TVs have the same resolution, regardless of screen size. Also, standard TV has an aspect ratio of 4:3, meaning that for every one inch of width the screen is three inches high, making a TV screen almost square. Now, when you enter the world of digital High-Definition TV, that 480 line interlaced picture is a thing of the past. High-Definition gives us the ability to see up to 1,080 interlaced lines of resolution. Further, it also offers the advantage of viewing shows in progressive scan mode, meaning that instead of drawing half of the lines on the screen at a time, the entire image is shown on the TV screen at once. Progressive scan can display resolutions of either 480, 720 or 1,080 lines. Now, you might be saying that, even with a big 60-inch high-dev TV if you watch shows broadcast in analog you still will only get 480 lines even though the TV is capable of much more. This is not necessarily true. Many high-def TVs have line-doublers, which is software that actually enhances the standard TV signal so that it shows up on your big screen with no visible lines at all. And, if you are a DVD fan like me, a progressive scan DVD player will take your high-def TV to new heights that before seemed impossible to reach. With a high-definition picture, the images you see on your TV can almost be compared to looking through a freshly cleaned window. A picture on a high-def TV is so remarkably clear and crisp that many TV stars are so fearful that people will see what they really look like that they are getting cosmetic surgery to enhance their looks. It makes that much of a difference. Further, high-definition TV carries with it surround sound audio. No more with just the old-school left and right stereo. Now you can watch shows like ER with sound coming at you from all four corners of your living room. Last years Super Bowl was the one show that really made me appreciate both the excitement of football and the wonders of what high-definition can provide. Also, most high-def TVs have an aspect ration of 16:9, making the picture much wider than standard TV and helping to immerse us into the show by capturing more of our field of vision. There are so many different types of high-definition TVs on the market these days that it would take much too long to describe each. There are front and rear projection TVs, LCD, Plasma, DLP, among others. Prices range from just over a thousand dollars to more than $15,000, depending on brand, technology used, etc. Suffice to say that any high-definition TV will show a picture that will know your socks off. If you want to know more about the different types of high-def TVs, and which may be best for you, just drop me an email and Ill be happy to try and answer your questions. Now, for the Cool Site of the Week... This weeks site is CNet.com. The folks at CNet have what has to be some of the coolest jobs on the planetplaying with and writing reviews for electronic gadgets. Every time I am looking to buy any piece of electronic equipment, from a cell phone to a TV, one of the first places I go is CNet.com. The reviews are excellent and very thorough, and they even have some nice price comparisons so you know where to go to get the best deal. As always, if you have any questions or suggestions for future articles, please email me at mike@MikeBryant.com. |
