For blu-ray and hd dvd, is 720p better than 1080i?

Question

My 65 inch projection tv only goes as high as 1080i.

Now I've been told that 720p is better because 1080i only shows 540 lines at a time, the odd numbered lines first then the even numbered ones while 720p shows all 720 lines at once.

Any experts out there that can shed some light on the subject?

Answer 1

I'd be inclined to go 1080i, at least for DVDs/Blu Rays/HD DVDs. With a decent TV, the set should be able to interlace the signal and you'll get something pretty comparable to 1080p.

For other things, such as sports broadcasts, 720p may actually play better.

Answer 2

2 good answers (and two bad ones) so far.

Let me take a crack.

For HDTV some broadcasts are at 720p and some at 1080i, indicating the split of opinion on which is best. Bottom line is progressive (i.e. 720p) will give crisper images if there is fast motion, while interlaced (i.e. 1080i) giving a sharper image for slow or still images.

The reason for this is as you note: 1080i is a 1920x1080 resolution image (although drawn as two supeimposed and interlaced halves of 540 vertical lines (1,3,5, ... then 2,4,6, ...) to make the complete image), while 720p is a 1280x720 resolution image drawn as one series of 720 lines (1,2,3,4,5, ... i.e. progressive). They key point here is that while a higher number of dots makes for a sharper image, interlacing can lead to a slight mismatch of two halves of a rapidly moving image.

So which is better? Well, you will have to try it and see which looks better to you. There are a number of factors that can influence results, including your viewing position and eyesight, type of HDTV, quality of the electronics, incoming signal type and connection type (e.g. S-video, component, HDMI/DVI). Each influence either the actual quality of the resulting image or whether you will be able to see the difference.

In all cases where the signal is being provided by an external device (e.g. cable or satellite box, DVD or HD DVD/Blu-ray player) make sure you use the best connection available. Component is better than S-video and DVI or HDMI is usually equal or better than component.

For broadcast HDTV you should try both 720p and 1080i and pick whichever looks best to you.

For Blu-Ray or HD DVD the native signal is 1080p @ 24 frames per second (fps), although most 1st and 2nd generation players convert this to some other signal (e.g. 1080p/60fps, 1080i/60fps or 720p/60fps). You must therefore try the various outputs with your HDTV to see which works best since the quality of the electronics (scaler, deinterlacer) in the disk player may be better or worse than those in your HDTV.

Hope this helps.

Answer 3

720p is better than 1080i. The guy is right. 720 lines at once is definitely better than 1080 lines interlaced. But the catch is that it really doesn't make that much of a difference. That's why some people think 720p is better while others think 1080i is better (could be that people that sees it in 1080i had it paused, which makes it look better).

Answer 4

It depends. 720p is great for motion such as sports or action movies, but 1080i has more dots so any image is crisper. Another important factor is your eyesight. If you have less than perfect eyesight or any glare on the screen, you won;t be able to tell the difference between 720p and 1080i on pause.

Answer 5

Oh! Let me tell the matter.

720p means the resolution of 1080*720 in progressive scan.
progressive scan may cause of blurring of fast moving scenes.

1080i means the resolution of 1920*1080 in INTERLACED scan. This is the best coz it has no scanning it screens all image dots in the same time. so it cause no blurring even in very high FPS scenes.

Thanks!!!

Answer 6

you should match the resolution as close as possible to your set.

Answer 7

as far as i know, the later the letter in the alphabet, the better the resolution. (as in z is 26x better than a, or whatever.)