I am going to be shooting a music video with a lot of green screen footage in the next couple of days. It's going to be distributed mainly online, through the bands myspace, purevolume, music sites, etc. I'm a little new to HDV and I plan on shooting in 1080i/30fps. When I bring the footage into avid should I use the HDV codec or should I use pro res 422? I'm trying to get the best possible image in the end. Are there codecs better than others for green screen?

When I'm done editing, what should I use to export the final timeline? What codec do I use for the export? What should I export it as, a quicktime reference, movie?  I'm really kind of clueless on this, but again it's going to be distributed mainly online and I want the best possible image.

Any help would be awesome, I post on this forum every now and then because every one seems to be much more knowledgable than me, so thanks again.

-Brendan

First off, don't expect miracle chroma keys from HDV material.  The HDV format uses 4:2:0 chroma sampling as well as a thin raster of 1440 x 1080.  Whatever codec you use later isn't going to overcome the limitations of your originating format.  But, it's not that bad as long if your final product is released in a smaller size.  We'll get to that later.

The codec you use for capture is going to depend on how the signal gets into the Avid.  If you don't have any Avid HD hardware like an Adrenaline, Nitris DX or Mojo DX you'll be bringing the HDV into the Avid via Firewire in it's native form, so you'll be using the HDV codec.  You'll want to transcode the HDV into DNX145-TR (thin raster) which is more robust and less processor intensive than HDV before you start cutting.  Besides, HDV can't be exported from the Avid for conversion into other formats until it's converted into a intraframe format (like DNX) first.  (BTW, ProRes 422 is the Final Cut equivalent of Avid's DNX resolution.)

Once you're done cutting you can export a QT reference movie and use QuickTime Pro or Compressor or any other file conversion program to create your final delivery files.  You can also export directly from the Avid and use the export settings to create many of the same formats.  Some programs, like Compressor or Squeeze have preset settings for common delivery formats.  You should check with the various destinations to see what type of file they expect.  You can search the Forums here for more information or just post another question when you get closer to finishing the project.

No, unfortunately I do not have a mojo or adrenaline. I'm still in school, and they don't carry them here.  Now this might sound a little stupid, but do I transcode HDV material the same way you transcode audio 44.1 to 48 khz? I haven't done a ton of transcoding. Like I said before I'm a complete newbie, so I'm just trying to find my way. And would you suggest keying with spectramatte in Avid or send it into AE or Motion? And I will be transfering into the avid from a camera hard drive via firewire.

Thanks for all the help,

Brendan

Maghranimal:

...do I transcode HDV material the same way you transcode audio 44.1 to 48 khz?

not sure what you mean by that.  I think what hbrock meant is, once you have captured your HDV originated footage into Avid via firewire from the camera harddrive of yours, that footage now lives in Avid (but no transcoding has occurred during this capture process and your footage is still in its original HDV format).  Now you can use the "consolidate" tool/command to transcode your captured footage (that lives now in Avid) into DNxHD 145 TR codec.  

So, once done transcoding, in your project you'll have your footage sitting in two different formats, in its original native HDV format, as well as in the newly transcoded DNxHD 145 TR format.  You can now use the DNxHD 145 TR footage to cut.

hbrock:

Besides, HDV can't be exported from the Avid for conversion into other formats until it's converted into a intraframe format (like DNX) first.  (BTW, ProRes 422 is the Final Cut equivalent of Avid's DNX resolution.)

hbrock, you meant this for a QTime reference movie, right?  Because I believe you can export from a native HDV timeline to any format of your choice (a quicktime or an image sequence like TIFFs, etc) as a self-contained movie.

Hey thanks a lot for the response it really helps me understand these things a little more clearly. Should I export from the DnxHD 145 footage?

Thanks again,

Brendan