HD For Dummies

It can be so overwhelming with all of this talk of HD, HDTV and High Def, have you ever felt that way?

Going to Best Buys or Circuit City and asking one of their associates doesn’t help either as they gush out and bubble over with techno-geek language that simply goes right over your head sometimes.

So lets explain it in a simple and easy way so that you can buy the Television that you want without spending any more money than necessary.

What is HD?

HD stands for High Def or High Definition. It is describing the quality of the signal and picture that you see on your television.

Did you know that there are different degrees of HD?

At the time of this writing there are only three levels of High Definition signal or picture.

1)    720p
2)    1080i
3)    1080p

What Do The Numbers Represent?

The numbers represent the number of pixels on your television screen.

Lets discuss what you probably have right now…a normal, regular run of the mill television set.

Your existing TV shows a 480i picture. What this means is that there are 640 vertical “pixels” or dots x 480 horizontal “pixels” or dots that make up your TV picture.

It only makes sense then that the more “pixels” or dots you have or can show…the clearer, sharper and crisper the picture quality.

Does that make sense?

Well How Many Pixels Does An HDTV Have?

As we mentioned already, there are different levels of High Definition viewing available.

1) 720 p has 720 vertical pixels and 1,280 horizontal pixels

2) Both 1080i and 1080p have a resolution of 1,920 vertical pixels x 1,080 horizontal pixels

So then a 720p has a better picture than a standard 480 TV, and a 1080i TV or 1080p TV has a clearer picture than a 720p TV.

Are you following me so far?

Well Then What Do The “p” And The “i” Stand For?

Simply put, the “p” or the “i” refers to how the picture is refreshed on your television screen.
The “p” stands for “progressive”, while the “i” stands for “interlaced”.

What do these terms mean?

Imagine taking a paintbrush in your hand and with one stroke covering your entire TV screen. That’s exactly what happens with a “Progressive” signal. When you have a 720p or 1080p television all 720 pixels or 1080 pixels simultaneously are refreshed on your screen at the same time.

Now take that same paintbrush and just pain in every other line. First all of the even lines of resolution are pained in. Then 1/30 of a second later all of the odd lines of resolution are painted in. And so on and so on. This describes how a 1080i or “interlaced” signal is received on your TV.

As you can imagine a 1080p picture theoretically is a clearer picture then a 1080i.

Here’s something to think about before you rush off to buy a 1080p…
At this time all satellite channels and cable channels are only broadcasting a 1080i picture. In other words…a 1080p TV would offer no better picture then a 1080i.

The only reason you would buy a 1080p is if you are planning to buy a Blueray or HD DVD player, or an x-box since they are the only equipment that can produce a 1080p signal that you can see on a 1080p TV.

Learn what consumer reports has to say about buying a new TV.

Should you get a Plasma or LCD TV?

What do I need to know before installing a flatscreen TV over the fireplace

Why do you need to order an HDTV receiver from your cable or satellite provider?

Learn about the HDTV programming available to you.

If there is anything I can do to help you with your TV purchase, selection or installation please let me know.


F. Cheshire

Home Theater Consultant

(770) 561-3178

“Installing HDTV plasma & LCD Flat screens all over Atlanta Georgia ( Ga )”