How many versions of '720p' are there? (1 Viewer)

[Frank@N]

When shopping for LCDs in the past, I noticed that many different brands and models appeared to run at various 720-ish resolutions (per the price card).

This lead me to think that many manufactures were using oddball resolutions.

Problem with this is that an upconverting player set to '720p' won't hit the native rez of the display.

Are display resolutions starting to standardize or are upconverting players offering several resolution options?

I'm starting to think I would need to buy a TV and a player for the same company the same year in order to get 1:1 pixel mapping.

 

[Allan Jayne]

In the U.S. there are just two 720p formats that can go between the DVD player and the TV. One is analog consisting of 750 scan lines, 720 containing picture information. The other is digital consisting of frames 1280 pixels across by 720 pixels high. Both have approximately 60 frames per second.

TV's with 768 rather than 720 rows of pixels and 1366 rather than 1280 pixels across will probably continue to exist. So will TV's with a few other odd pixel counts. Most accept 720p, scaling the video up to exactly fill the screen.

While the analog format is (usually) constructed representing 1280 pixels per scan line, it is difficult although still possible, often requiring manual fine tuning, to get a 1:1 pixel match even with a 1280 x 720 display.

Video hints:
http://members.aol.com/ajaynejr/video.htm

 

[Frank@N]

It sounds like '720' sets are hard to pixel map, so I guess the typical person should get a prog scan player and just let the TV scale once (instead of having an upcon player scale once and the TV scale again).

Either that or wait for affordable 1080p sets.

I've also heard that 1080p sets will do a much better job of displaying typical 1080i signals (one post I read indicated that 720 sets throwaway a lot of data by only scaling one 540 field).

Some folks in the electronics business seem to gleefully think that all 720 sets will need to replaced in a few years.

I don't buy that really, but I'm little leerily of buying a larger 720 set as my current primary display (as opposed to a smaller bedroom unit).

 

[Allan Jayne]

A number of 1080p sets also throw away a lot of data, scaling up every other 540 line field. Unfortunately I don't know which ones they are.

If you make sure your 1080p set has a 1080p input, you can hitch a dongle to the back that does a better job of making 1080p out of any 1080i show if the TV doesn't do it well enough for you.

 

[Frank@N]

Would that involve putting a 3rd-party scaler into the loop before the signal hits the TV?

 

[Allan Jayne]

Yes.

A Lumagen HDP costs USD $1500. and does a better 1080i to 1080p and 1080i to 720p than 95% of the TV's currently being made (mid 2006). It will also convert to odd resolutions like 768p if your TV accepts it.