NOTE : THE PREVIOUS METHOD IS ONLY FOR IMAGE ONLY SEQUENCES.

If you want to MIX THE IMAGES WITH INTERLACED VIDEO you need to use a special video filter on the images called "Flicker Filter" (found in Effects->Video Filters->Video). This allows you to mix the images without messing up the interlacing of the video (which makes a big difference on a TV). So make sure you keep the Field Dominance as the default (probably lower-field with DV or upper-field with HDV) when you are mixing the images and interlaced video.

Also, if you are using a very high quality image with thin, detailed lines, you will want to add a tiny bit of a Gaussian Blur (found in Effects->Video Filters->Blur).

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Zack Wilson