Tv Resolutions: 720p, 1080i, 1080p

[spharis]

Lines of resolution was a standard used with analog signal, but actually is still a good standard for quality of a picture. It had nothing to do with the horizontal resolution of pixels. Beta-SP, D1, and even VHS all used the same NTSC standard, which comes out to 640x480, but Beta-SP provided 350 lines of resolution, while VHS only about 100 or so.

A little clarification: D1 NTSC standard is 720x486. To move to a computer and have the non-square pixels display right, or DV, it must be a square format like 640x480. or more appropriate 720x540 (for true D1 NTSC).

The "i" and "p" as probably already discussed stands for interlaced and progressive. Progressive is a full refresh each frame. interlaced is every other line, every other frame. If we go back to D1 NTSC (the standard), it is 29.97 (or 32 for DV) frames per second; Interlaced D1 will give you only 16 pictures per second, every other scan line is updated each frame. There are 486 (actually 525) scan lines. If you go progressive, it is like your computer monitor. Each frame the image is updated top to bottom left to right for every single frame.

So just using the D1 comparison, you can see that D1 NTSC 480i is only half the amount of data as D1 NTSC 480p. If you take those numbers up you can see that 720p is actually a better picture than 1080i, as it contains about the same amount of data as 1440 interlaced lines. Only problem with this is that sets are not universally rendering the images the same. Some do real time upconversion, some do pixel doubling, some try to draw the inbetween pixels to actually improve the picture quality. But in raw format, 720p is a better image than 1080i.

[ragboy]

Y, D1 is 720, but I didn't want to get into non square pixels. My point was, those formats, were all basically the same with pixels, but were measured by horizontal lines of resolution, which has nothing to do with pixel res.

[dogbert]

I just took exception to the fact that 720p will always look better than 1080i. That's just not true. It can, but it doesn't always.

If you don't believe me, go hook up a Blu-Ray or HD DVD to a Mitsubishi DLP and then play some movies with differing resolutions (720p-1080p) and see if you can tell the difference. It's like saying you can tell the difference between a computer screen refresh rate of 60 vs. 75.

BTW, spharis & ragboy are pretty smart guys. Maybe we should have a contest?

[ragboy]

You can tell the diff in screen refresh, if you are up close. Text looks crisper and stuff at 75, but thats the thing. At the distance we all sit watching TV is the issue.

Or we could put our heads together practice mind control. Bwah Ha Ha ha!

[Graham Morris]

720P vs 10801/p

I just took exception to the fact that 720p will always look better than 1080i. That's just not true. It can, but it doesn't always.

If you don't believe me, go hook up a Blu-Ray or HD DVD to a Mitsubishi DLP and then play some movies with differing resolutions (720p-1080p) and see if you can tell the difference. It's like saying you can tell the difference between a computer screen refresh rate of 60 vs. 75.

BTW, spharis & ragboy are pretty smart guys. Maybe we should have a contest?

the trouble with the concept of using a full 1080p screen/ projector and various resultions is that all LCD and Plasma screens are best and clearest at full resolution unlike crt/tv monitors.

I have a 60 inch 1080P plasma and a lcd HD 1080p projector to 120 inch screen linked to a denon upscaling amp and a bluray. Had a 720 p 50 " plasma previously. The amp upscaling my Satelite to 1080P is much better than the old 576i or 720P. However a true 1080P Bluray is much better again esp when you go 120". I find 1080i tv content very variable in quality. I suspect a lot is just low def stuff upscaled by the TV houses and called High Def.

[da.bell]

Well, I changed the Xbox 360 to 720p from 1080i. The colors a little more vivid with 720p. I will keep it there since I agree with Ragboy, after a certain number of feet, it is rather hard to tell the difference between 1080p and 720p. Since I am sitting about 20 feet back, I think I found the proper setting.

[stanger]

One of the biggest diffrences I found out when I bought my new Toshiba Regza 42" TV about 3 weeks ago was the 60hz to 120hz conversion it does and clears up the picture in a scene with fast moving objects accross the screen