Interlaced footage question at DVinfo.net

Geoffrey Cox · August 30th, 2009, 08:55 AM

Hi All,

I'm pretty new to HDV having worked in SD until now and I posted a question a little while ago about how footage (HDV 1920x1080, 50i) looked horribly blurred once imported into my Mac (it looked the same in FCP, QT etc). There were some useful responses but no real conclusions. Subsequently I think I realised this is largely an interlacing issue though I've never seen it this bad but I noticed that when I used VLC player and switched on Bob deinterlacing the blurriness diminished considerably though not entirely. I also found that selecting NO field dominance in FCP sequence settings had a similar effect. I also think that since my footage is PAL 50i then native 60Hz computer screens also cause problems. What a minefield all of this is!

I found to my relief that when I printed a FCP 6 sequence back to tape it looked as good as the original footage, all blurriness, judderiness etc gone. But I'm still confused because I haven't de-interlaced and am still watching it back on the same progressive monitor so how come the interlacing artifacts are virtually all gone? I should say that when I connect the monitor to my Sony HDV player it flashes up the resolution 1920 x 1080i @50Hz as it does when I use it as external monitor for FCP.

Does this mean that the only performance / distribution medium is going to be tape because whenever I play it from computer it looks poor - yes I could de-interlace (and I've tried this) but the pristine beauty of the original is lost.

I use a high spec MacBook Pro, FCP6 and view on a 1920x1200 Native Samsung 1080p LCD screen. The footage is from an XHA1

Any thoughts would be appreciated.

Geoff

William Hohauser · August 30th, 2009, 02:39 PM

Interlaced footage always looks bad on a computer monitor. Try exporting your project to h.264 using the standard QuickTime 7 presets in Compressor. It should look just fine on your monitor.

Mitchell Lewis · August 30th, 2009, 11:21 PM

Make sure your Canvas window (the main window you use to view your timeline) is set to 100%. At any other setting, it will make your footage look blurry.

But like William says, interlaced footage will never looking good on a computer monitor. You need to view it on a video monitor connected to a proper interlaced play back medium. ie: a DVD player connected to a standard television. Or a DV tape deck/camera connected to a standard television.

Geoffrey Cox · August 31st, 2009, 12:44 PM

Thanks for the suggestions William and Mitchell. Is there a way of using an ordinary TV as a monitor for FCP without having to go back to tape / burn DVDs?

I'm still confused though as to why when I use my progressive LCD monitor the footage looks so much better when viewed from tape than from the computer (either as a QT file or straight out of FCP) - what's the difference? - the material is still interlaced in both cases and the monitor the same...

William Hohauser · August 31st, 2009, 03:39 PM

The monitor is capable of converting it's scan rate to the material being played from the DVD player/VTR/cable box/antenna/etc.. Your computer is putting out a progressive signal but the interlaced clip it's playing is within the signal in a window so the monitor sets itself to progressive. QuickTime does not convert interlace clips to progressive on the fly. VLC does a decent job but it's not perfect.

August 30th, 2009, 08:55 AM	#1
Geoffrey Cox Major Player Join Date: Aug 2008 Location: Huddersfield, UK Posts: 469	Interlaced footage question Hi All, I'm pretty new to HDV having worked in SD until now and I posted a question a little while ago about how footage (HDV 1920x1080, 50i) looked horribly blurred once imported into my Mac (it looked the same in FCP, QT etc). There were some useful responses but no real conclusions. Subsequently I think I realised this is largely an interlacing issue though I've never seen it this bad but I noticed that when I used VLC player and switched on Bob deinterlacing the blurriness diminished considerably though not entirely. I also found that selecting NO field dominance in FCP sequence settings had a similar effect. I also think that since my footage is PAL 50i then native 60Hz computer screens also cause problems. What a minefield all of this is! I found to my relief that when I printed a FCP 6 sequence back to tape it looked as good as the original footage, all blurriness, judderiness etc gone. But I'm still confused because I haven't de-interlaced and am still watching it back on the same progressive monitor so how come the interlacing artifacts are virtually all gone? I should say that when I connect the monitor to my Sony HDV player it flashes up the resolution 1920 x 1080i @50Hz as it does when I use it as external monitor for FCP. Does this mean that the only performance / distribution medium is going to be tape because whenever I play it from computer it looks poor - yes I could de-interlace (and I've tried this) but the pristine beauty of the original is lost. I use a high spec MacBook Pro, FCP6 and view on a 1920x1200 Native Samsung 1080p LCD screen. The footage is from an XHA1 Any thoughts would be appreciated. Geoff

August 30th, 2009, 02:39 PM	#2
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	Interlaced footage always looks bad on a computer monitor. Try exporting your project to h.264 using the standard QuickTime 7 presets in Compressor. It should look just fine on your monitor. __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

August 30th, 2009, 11:21 PM	#3
Mitchell Lewis Trustee Join Date: Dec 2008 Location: Kennewick, WA Posts: 1,124	Make sure your Canvas window (the main window you use to view your timeline) is set to 100%. At any other setting, it will make your footage look blurry. But like William says, interlaced footage will never looking good on a computer monitor. You need to view it on a video monitor connected to a proper interlaced play back medium. ie: a DVD player connected to a standard television. Or a DV tape deck/camera connected to a standard television. __________________ Sony EX3, Canon 5D MkII, Chrosziel Matte Box, Sachtler tripod, Steadicam Flyer, Mac Pro, Apple/Adobe software - 20 years as a local videographer/editor

August 31st, 2009, 03:39 PM	#5
William Hohauser Inner Circle Join Date: Dec 2005 Location: New York City Posts: 2,650	The monitor is capable of converting it's scan rate to the material being played from the DVD player/VTR/cable box/antenna/etc.. Your computer is putting out a progressive signal but the interlaced clip it's playing is within the signal in a window so the monitor sets itself to progressive. QuickTime does not convert interlace clips to progressive on the fly. VLC does a decent job but it's not perfect. __________________ William Hohauser - New York City Producer/Edit/Camera/Animation

August 31st, 2009, 12:44 PM	#4
Geoffrey Cox Major Player Join Date: Aug 2008 Location: Huddersfield, UK Posts: 469	Thanks for the suggestions William and Mitchell. Is there a way of using an ordinary TV as a monitor for FCP without having to go back to tape / burn DVDs? I'm still confused though as to why when I use my progressive LCD monitor the footage looks so much better when viewed from tape than from the computer (either as a QT file or straight out of FCP) - what's the difference? - the material is still interlaced in both cases and the monitor the same...