High Definition Television – HDTV

 

With the gradual introduction of HDTV technology, television promises to have a better picture quality for the future. Here are a few details that may need to be considered.

 

1.              When buying a HDTV set, ensure that it is capable of receiving the improved picture quality. Flat panel wide screen TV, plasma or LCD does not necessarily mean it is capable of receiving HDTV. Look for the HD Ready logo.

 

2.              To receive HDTV, you will need to subscribe to a cable or satellite service. A fee will be payable for this service.

 

3.              Special cables are needed to run between the receiving box and the TV these are as follows: - Component cables (red, blue and green), or a DVI (digital visual interface) cable, or a HDMI (high-definition multimedia interface). The HDMI cable offers high quality uncompressed digital flow of video and audio data between receiver and the HDTV. Do not confuse the ‘Component’ cables with ‘RCA’ cables (these are coloured red, yellow and white or classed as an ‘S-video cable). If in doubt, please contact ABC Computer Services on 01375 404495.

 

4.              As with most manufacturers of electrical equipment, they do not always provide the correct cables for the electrical apparatus. When upgrading your TV service the company may provide these cables for you, if not, they will need to be purchased separately.

 

5.              When installing HDTV make sure it is tuned into the correct channel.

 

6.              HDTV is capable of displaying DVD’s in better picture quality. This quality would be 720p or 1080i using a DVI or HDMI connection. Current quality only displays pictures at 480 lines of resolution, which is the current standard for analogue televisions. A VHS tape will only display at 240 lines of resolution.

 

7.              With the advent of HD-DVD’s and Blu-Ray disks in the next few months high definition video quality will be on offer, but these are two competing standards. One of these standards will follow the fate of the Betamax video tape war of the early eighties, so it pays to weigh up your options, before purchasing any of these items.

 

8.              The disk capacity of HD-DVD is 15GB single layer, 30GB double layer and upto 90Gb for multiple layer disk. A Blu-Ray disk will hold 25GB for a single layer disk, 50GB double layer, and upto 200Gb on a multiple layer disk.

 

9.              It will be a few months, before these disks and capacities are available as cheaply as DVD’s are at the moment, however they may will be surpassed by larger storage capacities of flash disks in the not too distant future.

 

10.         The way HDTV works is that all the lines on the screen are drawn simultaneously in one-sixtieth of a second, which gives a crystal clear picture. DVD players must be ‘progressive scan’ models to take advantage of this. The old method of showing pictures on the screen used the ‘interlaced method’, (480i), which tales one-thirtieth of a second to draw the first even lines, then the odd lines to show the picture. Certain DVD can convert the signal to 720p or 1080i as mentioned in ‘6’.

 

11.         To ensure a better quality of picture is shown on High Definition TV’s from DVD’s, please check the following: - the DVD must display ‘wide-screen’, instead of ‘full-frame’, and its native format must be 16:9 aspect ration instead of 4:3 found in standard TV’s.

 

12.         Contrast Ratio: - The LCD panel determines the contrast ratio by blocking out light from the backlight - the blackness of the black, the brightness of the white define a monitors contrast ratio. The higher number the better – check a device by side by side comparison.

 

13.         As well as HDTV, the audio used in HDTV has also been upgraded. There are two different types DVD-Audio, developed by Pioneer, Panasonic and others and SACD (Super Audio CD) developed by Philips and Sony. The sampling rate used by these standards is higher than used on CD. CD uses 44.1KHz, whereas DVD-Audio and SACD use between 96KHz and 192KHz. The system uses a method called ‘Direct Stream Digital’. The content that these new disks can contain is text, graphics, and videos, so music can be played alongside photos and lyrics of an artist.

 

General Summary

 

The way of watching television has changed considerably in the last couple of decades, and will surely change again in the next few decades. It is no longer a straight forward experience of switching on the box, and plonking yourself down on the sofa, with a pint (the good old days). The array of equipment available is quite daunting, extremely complex, and expensive. Change will not happen overnight, but very gradually with a convergence of telecommunications and IT equipment. It pays to review what is required, budget and seek professional advice if unsure of what you need. Please contact ABC Computer Services on 01375 404495 for assistance.