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5.0 HDTV

Well... not really a quick guide.

Digital Video Resolution and Aspect Ratio Conversions

by dolphins See Profile edited by FastEddie See Profile
last modified: 2008-01-13 09:55:57

Digital does not always mean HD, but HD does mean digital.

• No, you do not have to subscribe to cable or satellite to get digital/HD broadcasts. Chances are most, if not all, of your local stations are broadcasting in digital, if not HD and can be rec'd using a standard UHF and/or VHF antenna.

• There is no such thing as a digital/HD-specific antenna. The same antennas made a few years ago are still being sold today and work just fine for digital TV. The manufacturers simply stuck stickers on the boxes or re-printed the boxes they use to include "Digital" and/or "HDTV".

• When analog broadcasts cease (scheduled for Feb 2009), you do not need to get an HDTV. Using your existing analog TV, you just need something to convert the digital signal to what your set can display. Digital-to-analog converter boxes will be produced for this purpose and coupons (limited quantity) will be made available by the US gov't to subsidize the cost of purchasing these.

• Digital cable or satellite is not the same as digital (OTA) broadcasting. The change-over date will not affect you (unless your provider wants to force you into a potentially higher cost tier of service).

Credit for this FAQ entry belongs to JTC See Profile

by Hall See Profile edited by Straphanger See Profile
last modified: 2008-03-09 19:07:55

This online calculator, Viewing Distance Calculator, can help you determine the ideal range to sit from your television.

• Be sure to specify if you're using a standard 4:3 (square) TV or a widescreen or 16:9 format TV as the distance does differ.

• Note that you do NOT have to enter a distance since you're trying to find out what's the proper distance. You can leave # 1 blank, specify the TV type on # 2, and fill in ONE of the fields for # 3. Most people don't know how "wide" their TV is since TVs are advertised based on their diagonal size, not their width.

Most people don't need to worry about a lot of the values it calculates. The last two, Maximum Viewing Distance for NTSC/PAL (720x480 / 720x576) (this is for standard-definition DVDs) and Maximum Viewing Distance to HDTV (Fully resolved 1080i, 1920x1080i), are what you're primarily after.

Credit for the link goes to dadkins See Profile

by Hall See Profile edited by FastEddie See Profile
last modified: 2008-01-14 20:46:23

Although your TV may have 1080p processing, this does not mean that your TV will accept a 1080p input source. Most TVs with 1080p capability execute this function by upscaling 480p, 720p, and 1080i input sources to 1080p for display on the screen. In essence, the 1080p function on your TV may be done with internal scaling or processing only and not be able to accept 1080p external source.

In order to take advantage of 1080p upscaling output from a DVD player, the HDTV must have both 1080p native display capability and be able to accept a 1080p signal from an external source.

In determining whether your 1080p compatible television achieves the 1080p result via internal scaling only, or can also accept 1080p signals from an external source, such as a DVD player with 1080p output, consult your user manual, which should explain what type your TV is. If you are still not sure, you can confirm this with tech support for your specific brand/model of 1080p compatible television.

Of course, another way to confirm this is to connect a DVD player with 1080p output capability to your Television via an HDMI, DVI, or Component (whichever output is designated for 1080p). Set the output of the DVD player to 1080p and see if you get an image on the screen.

You can go here for more information.

by H2OuUp2 See Profile edited by Straphanger See Profile
last modified: 2009-07-10 23:56:25

What do 720p, 1080i and 1080p mean?

High definition programs are encoded with a type of resolution: 720p, 1080i or 1080p. The number stands for the amount of lines embedded within the signal. The letter describes the type of scan the television uses to display the picture. The "i" means interlaced and the "p" means progressive.

Why does the amount of lines matter?

The number of lines on a television is important because it allows for greater detail in the image. This is a similar concept to digital photos and how dpi determines print quality. The type of televisions all of us grew up watching had 480 visible lines on the screen. By doubling the amount of lines in combination with the type of scan, HD essentially doubles the quality of picture.

Does it matter if the resolution is interlaced or progressive?

The type of scan is arguable considering the amount of lines for each HD format. Progressive scan is a better type of scan because it doubles the amount of times the TV displays the image per one second in comparison to interlaced. Still, the difference between 720p and 1080i is so minimal that is isn't an issue at all. While 1080p is better than 720p and 1080i, very few programs are made in this resolution so it really isn't a factor right now.

by H2OuUp2 See Profile edited by Straphanger See Profile
last modified: 2009-07-10 23:56:01