Buying a widescreen TV
Posted in: News - Thursday, February 18 2010
OK, so you’ve saved up some money and want to buy yourself a big wide-screen TV or projector. Here is some info that may prevent you buying an obsolete product.
Firstly you need to understand the basics. TV screen images are comprised of a mosaic grid of tiny squares called PIXELS, each one evenly colored. If you put a magnifying glass up to a Plasma or LCD TV screen you will be able to see them. Like the ancient Roman mosaic tile pictures, the smaller the tiles, the better the detail. From a normal viewing distance they blend together to form the picture. The more pixels built into the screen, the clearer (potentially) the picture.
Manufacturers will state the number of pixels in their TV, which is expressed as the number of pixels wide by the number of pixels high. This is called the screen’s RESOLUTION. For example, a “Full” HD screen has a resolution of 1920 pixels wide (horizontally) by 1080 pixels high (vertically) which is usually expressed as “1920 x 1080″. This is the highest resolution of TV’s currently available and is the type of TV that you should buy to be “future proof”. 1920 x 1080 is also the resolution of blu-ray DVD’s.
Now here is the misleading part where people often get confused. Some TV’s are sold as “HD ready” or HD (High Definition) as opposed to ” “Full HD” (Full High Definition). HD TV’s can be significantly cheaper than Full HD because they have less pixels and thus are cheaper to produce. Typically, HD TV’s will have a resolution of 1366 x 768 or sometimes even less. The difference in picture quality may not be noticeable if the screen 32″ (81cm) or smaller, or if you sit far away, or only watch SD (Standard Definition) TV broadcasts or standard DVD movies (which have a maximum resolution of only 768 x 576 for PAL countries or 640 x 480 for NTSC countries). But if you want to buy a very large screen, 40′ (101cm) or bigger then it is better to buy a Full HD TV with a resolution of 1920 x1080. SD Plasma or LCD TV’s are virtually no longer available as nobody wants them. Essentially they had the same resolution as the older style, curved glass picture tube (CRT) TV’s.
Most shows on TV are not yet Full HD or HD. This is changing as more shows are being produced in this new format, and eventually all new shows will be Full HD. So don’t be disappointed if your favorite show doesn’t look any clearer than it did with your old TV. It may not have been recorded in Full HD. Even dedicated free-to-air HD channels often transmit SD shows and the TV merely zooms in to fill your screen. SD has only about a quarter of the pixels of a Full HD image (roughly half the pixels wide by half the pixels high). They can’t create extra detail so this is what happens; SD video has it’s pixels “blurred” into adjacent pixels when displayed on a Full HD screen. You know you are watching a Full HD broadcast when you see a closeup of an actor that you thought had flawless skin, but now you can see every skin pore and wrinkle in their face!
I have tried to keep this post simple, there is a lot more I could tell you about TV specifications like refresh rates, contrast ratios, backlighting, plasma versus LCD etc. but this may be explored in future posts if any interest is generated by this one. Please leave a reply and tell me if I was too technical or maybe not technical enough. Happy viewing.
2 Comments for this entry
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Nicely informative. So I guess my DEL 24 inch monitor is Full HD. You can buy these for about $400 now (maybe less?). What you might also add is that most HD TVs also come with a tuner built in these days, when most of the time all we really need is a big monitor (because our set-top box also has a receiver built in). Either way, I’ve always thought it strange that if you were to have an HD TV, a VHS tape deck and a set top box, you’ve probably got THREE TV tuners in your set-up. I guess that’s mass marketing and who’s gonna argue with that?
On another note… Jim just offered to loan me his old DVD player, so between your loaned HD set-top box and his DVD player, I can feel a couple of cosy SD nights coming on..
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Roberto
February 20th, 2010 on 11:07 amGood point Edwin. Most HD TV’s do come with a built in TV tuner. There is also now a plethora of Full HD 1920 x 1080 computer monitors with HDMI inputs that could essentially be used as a TV, just by connecting a set-top box (digital TV tuner) and an amp and speakers -if they’re not already built in. I tried to keep the post as simple as possible for the lay person.
I don’t think there is much, if any difference between digital TV’s and widescreen computer monitors these days as the technologies have converged. If you want to buy a computer monitor to use as a TV, try and get one with a HDMI socket which carries both audio and video signals (if your computer monitor has inbuilt speakers). If it only has a DVI socket, this input only carries a Full HD video signal. This is still OK if you don’t have speakers inbuilt, but trying to find a set-top box with a DVI output may be hard. The only option then is to get a HDMI to DVI connector and connect the audio output RCA sockets to your audio amplifier. Warning: with the inclusion of HDCP (High-Bandwidth Digital Content Protection) in many devices, you may find you have issues connecting different devices or trying to send audio and video down separate cables. At best, you may only get analog stereo, at worst no audio and/or video. This issue is complex and it’s best to google HDCP issues before you buy products that are incompatible with each other.
Edwin
February 19th, 2010 on 10:18 pm