720 vs. 1080 debate

Barry Green · July 26th, 2005, 07:24 PM

They haven't. The HD100 only records two tracks of compressed audio. There is no provision for 4 tracks on the HD100.

4 tracks was talked about as a possible add-on to ProHD-XE, but is not part of ProHD or HDV.

Greg Gelber · August 2nd, 2005, 09:26 AM

Quote:

Originally Posted by Ken Hodson

Pushing the boundaries of compression just to promote 1080i when you are capturing an image that wouldn't fill 720p is only to sell cams to the sheep who need big numbers isn't an advancement.

WOW!!! You just sealed it for me. My line of freelance work doesn't nor will ever involve sending shows out for broadcast air or film premieres so I will be very happy with 720p compared to my SD projects. Thanks...

Douglas Spotted Eagle · August 2nd, 2005, 09:34 AM

Quote:

Originally Posted by Greg Gelber

WOW!!! You just sealed it for me. My line of freelance work doesn't nor will ever involve sending shows out for broadcast air or film premieres so I will be very happy with 720p compared to my SD projects. Thanks...

Not to continue what has already been an empassioned debate....
But if you don't like the upsample of DV to 720, wait'll you upsample 720p to 1080p. 1080i looks a lot nicer when resampled/deinterlaced to 1080p than 720 does, and while there are those saying we won't see 1080p for a long time....the displays have started shipping already, and so is the hardware. We're not that far off.
So, for short term you'll likely be happy with 720p, but the grail is 1080p.(60)

David Kennett · August 2nd, 2005, 03:48 PM

Quote:

Originally Posted by Douglas Spotted Eagle

Not to continue what has already been an empassioned debate....
But if you don't like the upsample of DV to 720, wait'll you upsample 720p to 1080p. 1080i looks a lot nicer when resampled/deinterlaced to 1080p than 720 does, and while there are those saying we won't see 1080p for a long time....the displays have started shipping already, and so is the hardware. We're not that far off.
So, for short term you'll likely be happy with 720p, but the grail is 1080p.(60)

I agree 1080p60 would be great (whats not to like?). I just would be surprised if cable, broadcast, satellite - whatever - will be willing to "spend" the additional data rate (double that of 1080i30 or 720p60) to deliver it. I know compression is getting better, but there will always be the pressure to deliver an optimum picture with the lowest data rate.

If you have read some of my posts elsewhere, you know that my logic follows thus:
1. CRT is the only really "true" interlaced display.
2. CRTs are disappearing.
3. Why create a picture in a format which MUST be converted to display it?

I would like to observe the comparison you make between 720p60 and 1080i30 converted to 1080p60. Such a test would require the highest quality source material (we're not judging relative merits of different cameras or display technologies - remember.)

I would be willing to bet that in 10 years virtually all of the display devices in people's homes will be 720x1280 or less. The CRT will have pretty much disappeared. It is possible that 1080p60 could be delivered with blue laser DVD to a somewhat limited audience (If they've decided by then!). An even higher resolution could be developed for theater use - perhaps the final nail in the film coffin.

But then that's just what I think will happen.

Thomas Smet · August 2nd, 2005, 04:24 PM

Spot I actually do not agree that 1080i going to 1080p will look much better than 720p to 1080p.

Since it isn't very easy to compare the camera formats right now I have been some testing in 3D Studio Max to compare quality between 720p, 1080i converted to 1080p and 720p, 1080i converted to 720p.

I have so far tried 4 different deinterlacing methods and for the most part there is very little to no quality difference between the two. I have rendered with many different antialiasing filters to try and better get what a camera would give us. Even using super sharp 3D rendered images there is little to no change. The more camera like the images get in terms of softness the closer both formats become. If the aim is 24p or 30p there is very little difference. If a 60 frame motion is needed than 1080i does have the advantage.

720p scaled up can get just a tiny bit softer but with very smooth results across the whole image.

1080i deinterlaced can be a tiny bit sharper but with either jagged edges or missing pixels on tiny objects or objects at a slight angle. If you use interpolation when you deinterlace the 1080i can get just as soft as the 720p (depends on which software you use)

I am using Shake to test the images by using 6 different scaling methods and 4 different deinterlacing methods.

I agree that 1080p would look better but 1080i is not in my opinion much better than 720p.

I will try and post some of my results in a few days. I want to study this a little bit further first.

Joe Carney · August 2nd, 2005, 04:47 PM

It will be awhile before 1080p is broadcast, but don't forget the Home Theater market, where you won't be limited by your local cable company. 108024 and 48p is already available on the high end, and just like technology in the past, it's only a matter of time before it's affordable for a sizeable minority. Since Blue Ray supports 1080p I'd say give it a couple of years. But the time to plan is now. I'm hoping the technology to uprez 720p with great quality is around soon too.

Barry Green · August 2nd, 2005, 05:08 PM

Quote:

Originally Posted by Joe Carney

It will be awhile before 1080p is broadcast

1080/24p or 1080/30p could be broadcast today, if broadcasters wanted to. Those are ATSC-sanctioned broadcast standards, with either the same (or lower) bandwidth requirements than 1080/60i.

The question mark seems to be about 1080/60p, which would seem to be years away from being broadcast, if ever. 1080/60p is not in the ATSC specifications, so it wouldn't work with any ATSC-compatible tuners.

Douglas Spotted Eagle · August 2nd, 2005, 05:22 PM

Quote:

Originally Posted by David Kennett

I would be willing to bet that in 10 years virtually all of the display devices in people's homes will be 720x1280 or less. The CRT will have pretty much disappeared. It is possible that 1080p60 could be delivered with blue laser DVD to a somewhat limited audience (If they've decided by then!). But then that's just what I think will happen.

I'll take that bet, gladly. I just hope I'm around in 10 years. I'll go so far as to suggest that it will go faster than 10. The first 30 shipments of 1080p displays were gone before they even hit ground, if you accept what Jon Peddie research has to say, and what most of the other research/advisement firms are saying. I know that I went to B&H a month back to see the one model they had on display. They'd sold it.

Tom,
My point isn't that 1080i is better than 720p. It is indeed sharper for fast motion, but it has its own issues as well. However, I *have* taken 720p and upsampled to 1080p, and have taken 1080i and crosssampled to 1080p (30) and viewed on both large and small LCD's, and on a Sony Qualia projector. 1080i converted to 1080p definitely looks better than 720p upscaled.
I have in my hands now, a GrassValley LDK 6000, courtesy of Lonnie Bates at the national repair center for Grass Valley. We've been doing some fun tests with it, more based around color than anything else. Calibrating these cams is definitely a learning experience. That said, I'm not even using one of the Sony cams to make my comparisons, I'm using the front end of a ViperCam.

Thomas Smet · August 2nd, 2005, 05:38 PM

Spot I would love to compare results as soon as I finish my tests. I am sure using a high end camera can give different results as to what I am doing. I will try to post my results in a few days.

What methods are you using to deinterlace? I will agree that a really good (but slow) deinterlacer will give good results depending on how much motion there is but most people would never think of using something like that except for short projects. I wouldn't want to do that on a 2 hour 3 camera concert for example.

I also wasn't saying one was better than the other. I actually think they are pretty much the same. I agree with you that the 1080i is a little bit sharper but with some bad aliasing edges. 720p is a little softer but a nice smooth overall image. I guess it all depends on how sharp you like your footage.

I will try to get the results up soon.

Bill Binder · August 10th, 2005, 11:59 PM

Since after 7 pages of responses no one has said it yet, this kind of topic has been hammered to death for YEARS in the avsforums. Not so much from the perspective of recording hardware, but tons from the perspective of display technology and what "looks" better. So, if you've never checked out the avsforums and you're interested in HDTV, go take a look... (BTW, I have no relationship to them at all, but it's a great forum to check out.)

David Kennett · August 11th, 2005, 08:30 AM

Bill,

I have been observing AVSForum for quite a while too! Never signed up though. There have been times I wanted to say something, but so far have resisted the urge. I have never been an extremist on the 1080i - 720p issue, and for some time thought (and still do) that 1080i was a little preferable. It is only recently that I began to realize that the CRT is disappearing. Interlaced scanning was DESIGNED for the CRT, and offers some disadvantages to progressive displays.

Soon, the street price of smaller flat panel displays (up to, say 30 inches) will be less than comparable tubes, and chip projectors are about that stage now. I'll bet that manufacturing costs of the newer technologies are already less than CRTs, but there are still development costs to recoup. In the not too distant future, you will not see a CRT at Best Buy or CompUSA.

Bill Porter · August 13th, 2005, 11:21 PM

Quote:

Originally Posted by Thomas Smet

If you were to shoot both 1080i/p and 720p both at 24 fps 720p would be much lower in terms of quality.

If I'm not mistaken,

A) there's a big difference between 1080i and 1080p so those shouldn't be lumped together

B) saying 1080i @ 24fps would have much higher quality than 720p @ 24fps is half right and half wrong. It would have more temporal resolution but the quality would suffer in terms of jaggies...

Graeme Nattress · August 14th, 2005, 08:09 AM

Quote:

Originally Posted by Bill Porter

If I'm not mistaken,
B) saying 1080i @ 24fps would have much higher quality than 720p @ 24fps is half right and half wrong. It would have more temporal resolution but the quality would suffer in terms of jaggies...

There's no such thing as 1080i24. There's 1080p24 embedded into 1080i60 with 3:2 pulldown though. If you've 720p24 and 1080p24, the temporal resolution is identical. I don't see how you think the 1080p24 in 1080i60 with 3:2 or whatever would have more jaggies just doesn't make sense. Can you explain more what you're getting at??

Graeme

Bill Porter · August 14th, 2005, 09:07 AM

Hey, I did say "If I'm not mistaken" ;-)

I was not aware there was no straight 1080i24, and that rather it is 1080p24 embedded into 1080i60. Is it captured as a true 24 fps progressive?

Graeme Nattress · August 14th, 2005, 11:31 AM

You can remove the pulldown after it's captured to get back to the original 1080p24. Obviously, some high end decks record and play 1080p24 without any pulldown, but then it's 1080p24, not 1080i60.

Graeme

August 11th, 2005, 08:30 AM	#101
David Kennett Major Player Join Date: Jul 2003 Location: North Ridgeville, Ohio Posts: 407	Bill, I have been observing AVSForum for quite a while too! Never signed up though. There have been times I wanted to say something, but so far have resisted the urge. I have never been an extremist on the 1080i - 720p issue, and for some time thought (and still do) that 1080i was a little preferable. It is only recently that I began to realize that the CRT is disappearing. Interlaced scanning was DESIGNED for the CRT, and offers some disadvantages to progressive displays. Soon, the street price of smaller flat panel displays (up to, say 30 inches) will be less than comparable tubes, and chip projectors are about that stage now. I'll bet that manufacturing costs of the newer technologies are already less than CRTs, but there are still development costs to recoup. In the not too distant future, you will not see a CRT at Best Buy or CompUSA. __________________ Dave

August 14th, 2005, 11:31 AM	#105
Graeme Nattress RED Problem Solver Join Date: Sep 2003 Location: Ottawa, Canada Posts: 1,365	You can remove the pulldown after it's captured to get back to the original 1080p24. Obviously, some high end decks record and play 1080p24 without any pulldown, but then it's 1080p24, not 1080i60. Graeme __________________ www.nattress.com - filters for FCP

July 26th, 2005, 07:24 PM	#91
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	They haven't. The HD100 only records two tracks of compressed audio. There is no provision for 4 tracks on the HD100. 4 tracks was talked about as a possible add-on to ProHD-XE, but is not part of ProHD or HDV.

August 2nd, 2005, 04:24 PM	#95
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	Spot I actually do not agree that 1080i going to 1080p will look much better than 720p to 1080p. Since it isn't very easy to compare the camera formats right now I have been some testing in 3D Studio Max to compare quality between 720p, 1080i converted to 1080p and 720p, 1080i converted to 720p. I have so far tried 4 different deinterlacing methods and for the most part there is very little to no quality difference between the two. I have rendered with many different antialiasing filters to try and better get what a camera would give us. Even using super sharp 3D rendered images there is little to no change. The more camera like the images get in terms of softness the closer both formats become. If the aim is 24p or 30p there is very little difference. If a 60 frame motion is needed than 1080i does have the advantage. 720p scaled up can get just a tiny bit softer but with very smooth results across the whole image. 1080i deinterlaced can be a tiny bit sharper but with either jagged edges or missing pixels on tiny objects or objects at a slight angle. If you use interpolation when you deinterlace the 1080i can get just as soft as the 720p (depends on which software you use) I am using Shake to test the images by using 6 different scaling methods and 4 different deinterlacing methods. I agree that 1080p would look better but 1080i is not in my opinion much better than 720p. I will try and post some of my results in a few days. I want to study this a little bit further first.

August 2nd, 2005, 04:47 PM	#96
Joe Carney Inner Circle Join Date: Jul 2002 Location: Centreville Va Posts: 1,828	It will be awhile before 1080p is broadcast, but don't forget the Home Theater market, where you won't be limited by your local cable company. 108024 and 48p is already available on the high end, and just like technology in the past, it's only a matter of time before it's affordable for a sizeable minority. Since Blue Ray supports 1080p I'd say give it a couple of years. But the time to plan is now. I'm hoping the technology to uprez 720p with great quality is around soon too.

August 2nd, 2005, 05:38 PM	#99
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	Spot I would love to compare results as soon as I finish my tests. I am sure using a high end camera can give different results as to what I am doing. I will try to post my results in a few days. What methods are you using to deinterlace? I will agree that a really good (but slow) deinterlacer will give good results depending on how much motion there is but most people would never think of using something like that except for short projects. I wouldn't want to do that on a 2 hour 3 camera concert for example. I also wasn't saying one was better than the other. I actually think they are pretty much the same. I agree with you that the 1080i is a little bit sharper but with some bad aliasing edges. 720p is a little softer but a nice smooth overall image. I guess it all depends on how sharp you like your footage. I will try to get the results up soon.

August 10th, 2005, 11:59 PM	#100
Bill Binder Major Player Join Date: Jun 2005 Location: San Francisco Posts: 542	Since after 7 pages of responses no one has said it yet, this kind of topic has been hammered to death for YEARS in the avsforums. Not so much from the perspective of recording hardware, but tons from the perspective of display technology and what "looks" better. So, if you've never checked out the avsforums and you're interested in HDTV, go take a look... (BTW, I have no relationship to them at all, but it's a great forum to check out.)

August 14th, 2005, 09:07 AM	#104
Bill Porter Major Player Join Date: Mar 2005 Location: Ventura, California, USA Posts: 751	Hey, I did say "If I'm not mistaken" ;-) I was not aware there was no straight 1080i24, and that rather it is 1080p24 embedded into 1080i60. Is it captured as a true 24 fps progressive?