Help! Here is my dilemna that I'm hoping to explain well enough for someone out there to help me with. I am editing a video that was shot on P2 cards in HD (1080I/60) and then transcoded to dv25 for editing. Final mastering is in 16x9 SD. The problem I'm running into is that there is a ton of footage where a host is Chromakeyed over backgrounds and, even using the spectrakey, I am getting dv artifacting which I have been unable to remove. What I would like to do is somehow bring in all of my host footage as either 1-1 or dv50 so that I can pull a better key. How do I best do this? I'm assuming its some combination of unlinking and relinking to the P2 material. Do I have to transcode everything again or can I create some kind of link from my edited sequences to the P2 material which is all stored on an external hard-drive? I'm on an adrenaline using 2.81 software. Any help or advice would be greatly appreciated. DAN

As you've just found out the hard way, Dan, DV is not a great format for chroma key.  You will get the best key if create a HD project for that purpose and bring the key footage into that.  Do your composites there and export a QTref of them.  Go back to your SD project and import.  Edit them into your timeline.

Alternatively you could mixdown the keys in the HD project and transcode the mixdown to SD, but I the first way creates less media.

The other way is to bring in your P2 media again and transcode to 1:1 SD before keying, but because you're starting with lower res your key will be harder to set up and may not be as good.