FREQUENTLY

ASKED QUESTIONS

WHAT IS HDTV? WHAT ADVANTAGES DOES IT HAVE OVER STANDARD DIGITAL TV ?

HDTV,or high-definition television, is a next-generation standard for digital television that gives you an image with superior resolution. Standard televisions display approximately 210,000 pixels, compared to over 2 million for top-end HDTV – a tenfold increase over traditional TV. Plus, HDTV enhances the home theatre experience by allowing for wider screens with aspect ratios of 16:9. Among other things, this can preserve a film’s original letterbox format.

IF I DON’T HAVE AN HDTV,WILL AN HD TERMINAL GIVE ME A SHARPER IMAGE?

No. Vidéotron’s HD terminals are perfectly backward compatible with traditional TV,but to take advantage of the higher resolution offered by HD broadcasts, your television must be physically capable of displaying the necessary number of pixels – and must be equipped with connectors that can carry this type of signal (Component/DVI/HDMI input).

TECHNICALLY,WHAT’S THE DIFFERENCE BETWEEN HDTV AND TRADITIONAL ANALOG SDTV?

There are several technical differences between standard, NTSC-format television and HDTV. (Technology varies widely even among HDTVs: CRT, LCD, Plasma, DLP,etc.)

TVs project programs onto their screens in the form of tiny picture elements, or pixels: 480 lines of pixels make up the picture on a standard analog TV. In comparison, HDTV images use 720 or 1080 lines, which results in much sharper detail and general picture resolution.

This also lets the image be “painted” in different ways. On an SDTV,the screen is painted using interlaced scanning, meaning that each of the 30 images appearing on screen each second is made up of two half-images: one each for the odd and even lines. HDTV can use either interlaced or progressive scanning (the latter changes the entire image from the first to last line up to 60 times a second).

The two HDTV formats:

720p 720 lines of horizontal resolution and progressive scan

1080i 1080 lines of horizontal resolution and interlaced scan

WHICH IS BETTER, 720P OR 1080I? HOW DO THESE COMPARE WITH DVDS OR THE TRADITIONAL DIGITAL TERMINAL FORMAT?

Progressive scan provides superior results compared to interlaced scan, the main difference being that interlaced scan’s alternating lines are more readily visible to the naked eye.

While a 720p image contains fewer pixels than a 1080i image, it also can be refreshed more quickly, making it the better choice for programs featuring a lot of movement, such as sports broadcasts.

To compare: both SDTV and DVD images use 480 horizontal lines with interlaced scan (480i). So-called progressive scan DVD players provide images in 480p format, resulting in better picture quality.

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Mintek High Definition Personal Video Recorder manual Frequently Asked Questions