HD1080i De-mystify HDTV 1080i ::: know why before you buy

Tuesday, September 18, 2007

HD Resolutions: 1440, 1366x768 and 1080i broadcasting

Wide screen and the old CRT square screen...

1) FOX and ABC HD is square with black rectangles to each side. how is this HD?

This is called HD Pillarbox. Basically its is SQUARE HD, as in not widescreen.

-- there is a burgeoning 3rd display resolution of 1440 wide image in a 1920x1080i broadcast.

Almost all hd broadcast is 1080i. for standard 4:3 TV content which is not widescreen 16:9, some channels are 1080 in a 4:3 format. simple math e.g.

1080 * 4/3 = 1440 wide image is a 1080i broadcast (square image)
1080 * 16/9 = 1920 wide image is widescreen HD broadcast.

Sometimes this is generated HD, upscaled from quality STD definition source by a special device used to create the claim that HD is being delivered. The old days of 720p broadcasting claims are dissappearing, replaced by this format. It matters, since to many people a wide screen is what they bought and wide image HD is what they want. I dont not consider this a valid HD outcome, but it allows for simulcast Standard def and HD without having 2 formats to produce, and cost 2 times as much as a result.

The other issue is that analog 4:3 STD definition uses a non-square pixel shape, .9091 : 1 to be exact. Most people dont know this. Analog nonsquare pixels , converted from analog to digital pixel conversions to digital square pixels are issues handled by production people. This should be transparent to average user, but it does in fact make you look 10lbs heavier on screen. ( a bit wider so to speak )

2) WHY is there 1366 x 768 HD display resolution? "I just got a great deal on my flatpanel and now i'm reading that its not really HD, and the picture is fuzzy."


We get this way too much. More than half the search strings in are weblogs read like this. Basically it costs less and thats why you pay less for the 1366 displays. It isnt a bad thing, and if your eyesight is not eagle sharp 20-20 perfect, then you may well be quite happy with that for years to come. Almost all manufacturers now make displays with well crafted scaling engines for placing 1080i (1920 x 1080 ) sources into a 1366 x 768 screens, looks great since the incoming 2 mpix of data is way more data than the 1 megapixel of the display.

The fuzzy picture may well be the source and not the display. A lot of broadcast TV is STD definition and inherently fuzzy to begin with. Spreading that out over a larger area only makes the fuzziness larger also.

Advice:

The biggest problems are when you attempt to connect a computer to a VGA input of a 1366 x 768 display. I have a whole post on that, it has lots of complex issues, but it usually can be done, and if you read the manuals many have a 1280x768 mode that wont fill the screen but will work. In some cases its worth asking the store before you buy, what VGA modes does this tv support? If you can , upgrade your computer to have DVI output and get a TV with a DVI input.
For me that is the nVidia 7600 GT graphics card and a westinghouse digital 1080p

Read http://hd1080i.blogspot.com/2006/12/1080i-on-1366x768-resolution-problems.html

If you have a 1366 x 768 display then dont bother to buy an HD-DVD or Blu-ray, and get an OPPO upscaling DVDplayer instead. It will look great and you will be happy with that at a much lower cost.

NOTE: We Don't post all comments since those that want responses directly leave email addresses in them that should not be made public and open to spammers.... I got a few comments that indicate some readers are in fact fully aware of these resolution situations and Overscan, safe area in 4:3 STD NTSC and Variations in Color Gamut. Thanks - you guys are great and i will post more on each area.

2 Comments:

Blogger Ben said...

You really should mention that all TVs have overscan and that even if the TV was 1280x720 that the viewer still wouldn't see an unaltered image.

5:43 AM  
Anonymous Anonymous said...

Is a native 1440x900 panel just as bad as the aforementioned 1366x768? Or even worse?

12:56 PM  

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