How good looks 35 Mbps codec when shooting leaves in wind?

Michael Mann · May 14th, 2008, 01:00 AM

Quote:

Originally Posted by Steve Mullen

Which camcorder is the correct way of looking at encoding issues.

I see. I was referring to the Canon HV30.

But I don't see the influence of VBR. On detailed motives the EX1' VBR should be always on maximum. That means it acts like maybe CBR 38 Mbps. So it is 25 vs. 38 Mbps in terms of data rate, right?

Gregory Murphy · May 22nd, 2009, 09:54 AM

Hi. I'm new to HD and we have just bought 2 JVC HM700s. I am wondering why what is the main difference in shooting in SP(which I think is 19mbps) or HQ(which I think is 35mbps). Is the difference really noticible. Is the picture sharper or just better for fast moving objects? Is there any point in shooting a wedding in 1080p rather than 720p. There are so many formats available on the JVC and I am a bit confused as to which I should be using. Using SP gives me more memory space on the SDHC cards which suits weddings. Can anybody help me?

Markus Klatt · May 24th, 2009, 07:45 AM

Here are two more samples from leaves in the wind, directly from the EX1, no post or reencoding. Will run fine in VLC.

This footage is around one month old and was shot just for some interlacing and downscaling tests. Now thoughts were spend on good picture quality. I think I used STD3 in a picture profile without detail settings with ND-filter on. There was much light that day and everything looks rather pale. Its 1080/50i HQ.

Enjoy the CA in first test. Both scenes were totally zoomed in, first is around 100m away, second maybe 20m:

http://78.46.70.4/tmp/test_01.mp4
http://78.46.70.4/tmp/test_02.mp4

(both are ~100MB in size)

Bill Ravens · May 24th, 2009, 08:05 AM

One of the main reasons I shoot 720P is because 720P downrezzes to SD much more cleanly than 1080. If your final distribution media is DVD, I'd seriously consider 720P.

Markus Klatt · May 24th, 2009, 08:18 AM

Many thanks for the hint! But probably this is very OT in this thread. I shoot for Blu-ray AND for DVD (same footage). I shoot 1080 because on large screens one can see fundamental differences to 720, in my opinion. And I need 50 frames because of fast moving objects in my footage. So, there seems to be no alternative to 1080/50i. But there are some (complex) workflows mentioned here in forums which produce very good results, for my taste.

Bill Ravens · May 24th, 2009, 08:33 AM

If you do a little research, I think you'll find 720P is probably a little better, resolution-wise, than 1080i, given the same data rate. Vertical resolution with 1080i is more like 540, although horiz. resolution is better than 720. At 35mbps, and long form GOP encoding, horizontal resolution in high motion scenes is limited by compression artifacts. In my own tests, I've found 50mbps is the minimum encoding bitrate mitigating horizontal compression artifacts in long form GOP mpeg2.

Markus Klatt · May 24th, 2009, 08:41 AM

[OT]
Thanks again, really! I've read that before, yes, and there are some tests, where people could not decide what was sharper, 720p or 1080i. Maybe this is due to the simple component cable or some settings in my TV, but when I connect the EX1 to my 50'' Pioneer Kuro one immediatly can see that 1080i looks sharper than 720p. I will check this further, I am just at the beginning of EX-HD filming after several years of SD.
[/OT]

May 22nd, 2009, 09:54 AM	#17
Gregory Murphy New Boot Join Date: May 2009 Location: Emyvale, Ireland Posts: 11	35mbps? Hi. I'm new to HD and we have just bought 2 JVC HM700s. I am wondering why what is the main difference in shooting in SP(which I think is 19mbps) or HQ(which I think is 35mbps). Is the difference really noticible. Is the picture sharper or just better for fast moving objects? Is there any point in shooting a wedding in 1080p rather than 720p. There are so many formats available on the JVC and I am a bit confused as to which I should be using. Using SP gives me more memory space on the SDHC cards which suits weddings. Can anybody help me?

May 24th, 2009, 07:45 AM	#18
Markus Klatt Regular Crew Join Date: Jul 2004 Location: Berlin, Germany Posts: 169	Here are two more samples from leaves in the wind, directly from the EX1, no post or reencoding. Will run fine in VLC. This footage is around one month old and was shot just for some interlacing and downscaling tests. Now thoughts were spend on good picture quality. I think I used STD3 in a picture profile without detail settings with ND-filter on. There was much light that day and everything looks rather pale. Its 1080/50i HQ. Enjoy the CA in first test. Both scenes were totally zoomed in, first is around 100m away, second maybe 20m: http://78.46.70.4/tmp/test_01.mp4 http://78.46.70.4/tmp/test_02.mp4 (both are ~100MB in size)

May 24th, 2009, 08:05 AM	#19
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	One of the main reasons I shoot 720P is because 720P downrezzes to SD much more cleanly than 1080. If your final distribution media is DVD, I'd seriously consider 720P.

May 24th, 2009, 08:18 AM	#20
Markus Klatt Regular Crew Join Date: Jul 2004 Location: Berlin, Germany Posts: 169	Many thanks for the hint! But probably this is very OT in this thread. I shoot for Blu-ray AND for DVD (same footage). I shoot 1080 because on large screens one can see fundamental differences to 720, in my opinion. And I need 50 frames because of fast moving objects in my footage. So, there seems to be no alternative to 1080/50i. But there are some (complex) workflows mentioned here in forums which produce very good results, for my taste.

May 24th, 2009, 08:33 AM	#21
Bill Ravens Join Date: Nov 2001 Location: santa fe, nm Posts: 3,264 Images: 10	If you do a little research, I think you'll find 720P is probably a little better, resolution-wise, than 1080i, given the same data rate. Vertical resolution with 1080i is more like 540, although horiz. resolution is better than 720. At 35mbps, and long form GOP encoding, horizontal resolution in high motion scenes is limited by compression artifacts. In my own tests, I've found 50mbps is the minimum encoding bitrate mitigating horizontal compression artifacts in long form GOP mpeg2.

May 24th, 2009, 08:41 AM	#22
Markus Klatt Regular Crew Join Date: Jul 2004 Location: Berlin, Germany Posts: 169	[OT] Thanks again, really! I've read that before, yes, and there are some tests, where people could not decide what was sharper, 720p or 1080i. Maybe this is due to the simple component cable or some settings in my TV, but when I connect the EX1 to my 50'' Pioneer Kuro one immediatly can see that 1080i looks sharper than 720p. I will check this further, I am just at the beginning of EX-HD filming after several years of SD. [/OT]