Help with understanding 540p and 1080i

[kalooz00]

I just bought the 65hx83. I am trying to understand the differences between 540p and 1080i.Most dvd's are 480.I do not have a setting for 480 what should I set the tv on?This is all new to me so please forgive my ignorrance.

[kalooz00]

I just bought the 65hx83. I am trying to understand the differences between 540p and 1080i as these are my only two options with this tv.Most dvd's are 480.I do not have a setting for 480 what should I set the tv on?This is all new to me so please forgive my ignorrance.

[57U]

Set your TV on the setting that gives you the best picture. You can try 540P or 1080i.

You can also try 480P or 480i on your DVD player. Try all the settings and see what you like best.

The 540P setting doesn't affect HD inputs since it will be "greyed out" and all incoming HD will be displayed as 1080i.

[kalooz00]

If I pick 540 or 1080 will it convert it from 480?How does this work?

[57U]

It will convert and it works the same way all "conversion" works. There's a processor in the TV that takes the incoming signal and converts it to the display format.

There are all kinds of possible incoming signals to various TVs - 480i, 480P, 720P, 1080i. If the display format is not the same as the incoming signal, the signal gets converted.

In the case of the Hitachi (and most HDTVs), 480i and 480P signals get "upconverted" so they typically look better than the original.

[kalooz00]

Thanks for the help.

[LeeS]

Sorry, a little late, didn't see 57U's reply.

I am trying to understand the differences between 540p and 1080i
Your Toshiba, like mine has two display modes, 540p and 1080i. Both these display modes use the same horizontal sweep frequency. Simpler and less expensive to build.

540p displays all 540 lines each time, 1080i displays 540 lines twice, interlaced or every other line.

All incoming 480i and 480p and converted to 540p for display. 720p is converted to 1080i for display. All you ever see is 540p or 1080i.

You didn't ask the following, but I'll throw it in :)

Question, why use a progressive scan DVD player to send 480p to the TV if its going to convert it to 540p anyway? Just send 480i (interlaced) and let the TV do the work.

I have a 'decent' DVD player and I've tried it both ways. It may be me but honestly I have a hard time seeing any difference. I use the 'progressive scan' output from the DVD player because it should be better :) and using 'FULL' for enhanced DVD's is easier.

Maybe its easier (better?) to convert a progressive, non-interlaced, signal to 540p?

Lee

[LeeS]

I merged the two threads. So my reply shows up in this one. Although its a little late (as usual).

You don't need to double post, use the 'view new posts' option and see 'everything' that's new. (we do) :)

Lee

[hawks066]

I never noticed a difference between 540p and 1080i on SD programming.

[freeness]

Look at like this. The TV will display 32400 lines per second. It's either displaying 540 lines 60 times per second or 1080 lines 30 times per second.

The TV upconverts 480i/p signals to 540p, so that the CRT's only need to have 1 scan rate.

Prpgressive DVD's should look better because the DVD player is sending twice as much data to the TV (read lines per second) as an interlaced DVD player. Even though the TV is going to convert to 540p either way, the more data the TV receives, the less conversion is needed and the better the picture.

It's like enlarging a digital photo. THe higher the resolution of the photo the larger you can make it before the image quality degrades.

Andy

[57U]

Originally posted by freeness It's like enlarging a digital photo. THe higher the resolution of the photo the larger you can make it before the image quality degrades.
This is true for photos, but with DVDs the "original" is encoded as 480i, so if the DVD player deinterlaces (in digital domain) and then sends the signal to the TV as 480P, or if the TV simply upconverts the 480i signal may not make much difference.

As a matter of fact, if the ultimate display mode is 1080i, it has often been found that it's better to leave the signal from the DVD player as 480i because then you "avoid" deinterlacing and reinterlacing.