[ This article was first published in the April, 2009, issue of
Larry’s Final Cut Pro Newsletter. Click here to subscribe. ]
Ellie Whitcomb writes:
I mostly edit sales reels for some shows that we sell. I get all different kinds of source material. Sometimes I’m lucky enough to have a master tape, sometimes I export the project myself from Final Cut, but mostly I deal with ripped DVDs. Probably, some of the older DVDs have undergone numerous rounds of compression. This is where my frustration comes in.
I know once quality is lost, I’m never going to get it back, but what is more frustrating is I always end up with field issues. Lines in the video, or shifty transitions. And I can’t ever see these problems until I put my final edited DVD on a TV screen. I don’t see the problems when I play it on my computer. Is there any rule of thumb or manual that will help choose the correct export settings when I rip a DVD (I usually go through MPEG Streamclip)? When do I Deinterlace, how do I know whether to use Upper or Lower fields? Is it just trial and error?
Larry replies: Ellie, thanks for writing. All SD videos displayed on a TV – or burned to a DVD for that matter – are interlaced. Both NTSC and PAL are interlaced.
So, you don’t want to deinterlace unless you are going to the web. This is because deinterlacing reduces the overall quality of the image.
NTSC and PAL video are both even (or lower) field dominant. This means that they display the even fields first, then the odd fields.
Note: Here’s an Apple tech support article that explains this in more detail: http://support.apple.com/kb/TA26010?viewlocale=en_US
Complicating this is that unless you set Final Cut to display your video at EXACTLY 100% in either the Viewer or the Canvas, you will never see interlacing in Final Cut, as it only shows you one field at a time.
So, set your export settings to DV NTSC (or DV PAL), since DV has higher quality than the DVD does, with field dominance set to Even. Set NTSC frame rate to 29.97 fps and PAL frame rate to 25 fps.
UPDATE – April 4, 2009
Eric Mittan adds:
Working in a newsroom where a portion of our archive video is stored as video DVDs, and where we’re often using footage brought to us by the public on DVD, I’ll agree with Larry that you shouldn’t be deinterlacing your footage to go back out to DVD.
The one exception I will make is that if you are doing anything with the geometry of your video in the Motion tab, you MAY need to deinterlace. If, for example, you move your center on the Y axis (this is the second number in the Center attribute in the Motion tab) anything other than a WHOLE, EVEN number, you should deinterlace, as you could potentially end up aligning the odd numbered fields of your source footage with the even numbered fields of your output footage, and the even numbered fields of your source with the odds of your output.
Larry replies: Eric, I mostly agree. However, I don’t think deinterlacing should be the first choice. Instead, I strongly recommend that if you are compositing two interlaced images, both scaled to 100%, you MUST make sure the Y value, circled in red below, is an even whole number.
Otherwise, the foreground image will become very soft and blurry. If you absolutely can’t set the second value to an even, whole number, then deinterlace.