File size from XH A1 vs. HV20 at DVinfo.net

Garrett Low · July 21st, 2008, 12:26 PM

Is there a reason why the AVI files from my XH A1 are about twice the size of the identical length of footage shot with my HV20? I use NeoHDV and notice that approximately 1 hour of footage from my XH A1, when transcoded into Cineform Intermediate high quality comes out with an AVI that's about 25 to 30 gigs. The same length of footage (shooting the same scene) from my HV20 comes out with a file that's about 15 GB.

Nothing is wrong with either AVI file but they are way different in size.

David Newman · July 21st, 2008, 12:32 PM

The HV20 is softer, lower resolution (single sensor) but true 24p, which will produce smaller output files. The Canon XH A1 is three chip, which very high horizontal resolution but only a pseudo 24f (24F is produced from an interlaced sensor) -- the each horizontal reosolution and the slight jaggies in the vertical, produce more picture information, therefore bigger files.

Garrett Low · July 21st, 2008, 12:37 PM

Thanks David,

Has anyone else reported any problems capturing with the latest update of HDlink? The last couple of tapes were giving me problems. When using HDlink there were a large number of dropped frames. This usually occurred after 20 minutes. The next time I captures it had some more dropped frames but at a different section so it wasn't the tape. I cleaned the heads and still had some problems. I ended up capturing with Vegas 8 then batch converting using HDlink.

When veiwing the tape on my tv or through the viewfinder there were no problems. Any ideas what could be causing this?

David Newman · July 21st, 2008, 12:48 PM

If you can, try a difference firewire port. We haven't change the HDV capture engine.

Jose Ortiz · July 21st, 2008, 04:48 PM

I had this issue before.
I was using a Firewire cable (monster brand from B&H). In my last capture project I used a different FW cable from walmart and the problem it's gone so far. Every time that I'm going to capture a new file of an hour long or so I reeboot my computer first. I can see an improvement of the speed in the conversion.

Chris Barcellos · July 21st, 2008, 05:18 PM

Quote:

Originally Posted by David Newman

The HV20 is softer, lower resolution (single sensor) but true 24p, which will produce smaller output files. The Canon XH A1 is three chip, which very high horizontal resolution but only a pseudo 24f (24F is produced from an interlaced sensor) -- the each horizontal reosolution and the slight jaggies in the vertical, produce more picture information, therefore bigger files.

David:

Wow. This blows me away. So question is, I have an FX1 (3 chip, and an HV20) single chip. If I shoot both in 60i, will I similarly get a smaller file for the HV20 ?

David Newman · July 21st, 2008, 05:23 PM

FX1 only has 960x1080 sensors (XH A1 has 1440x1080 sensors) so the different (if at all) will be much less. Also interlace will bump the data rate of both.

July 21st, 2008, 12:26 PM	#1
Garrett Low Trustee Join Date: Jul 2007 Location: Novato, CA Posts: 1,774	File size from XH A1 vs. HV20 Is there a reason why the AVI files from my XH A1 are about twice the size of the identical length of footage shot with my HV20? I use NeoHDV and notice that approximately 1 hour of footage from my XH A1, when transcoded into Cineform Intermediate high quality comes out with an AVI that's about 25 to 30 gigs. The same length of footage (shooting the same scene) from my HV20 comes out with a file that's about 15 GB. Nothing is wrong with either AVI file but they are way different in size.

July 21st, 2008, 12:32 PM	#2
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	The HV20 is softer, lower resolution (single sensor) but true 24p, which will produce smaller output files. The Canon XH A1 is three chip, which very high horizontal resolution but only a pseudo 24f (24F is produced from an interlaced sensor) -- the each horizontal reosolution and the slight jaggies in the vertical, produce more picture information, therefore bigger files. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

July 21st, 2008, 12:48 PM	#4
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	If you can, try a difference firewire port. We haven't change the HDV capture engine. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

July 21st, 2008, 05:23 PM	#7
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	FX1 only has 960x1080 sensors (XH A1 has 1440x1080 sensors) so the different (if at all) will be much less. Also interlace will bump the data rate of both. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

July 21st, 2008, 12:37 PM	#3
Garrett Low Trustee Join Date: Jul 2007 Location: Novato, CA Posts: 1,774	Thanks David, Has anyone else reported any problems capturing with the latest update of HDlink? The last couple of tapes were giving me problems. When using HDlink there were a large number of dropped frames. This usually occurred after 20 minutes. The next time I captures it had some more dropped frames but at a different section so it wasn't the tape. I cleaned the heads and still had some problems. I ended up capturing with Vegas 8 then batch converting using HDlink. When veiwing the tape on my tv or through the viewfinder there were no problems. Any ideas what could be causing this?

July 21st, 2008, 04:48 PM	#5
Jose Ortiz Major Player Join Date: Dec 2006 Location: Tampa Florida Posts: 347	I had this issue before. I was using a Firewire cable (monster brand from B&H). In my last capture project I used a different FW cable from walmart and the problem it's gone so far. Every time that I'm going to capture a new file of an hour long or so I reeboot my computer first. I can see an improvement of the speed in the conversion.