Re: Working with interlaced footage

no no, you are useing one object with two materials on it, one material is for the even fields and one material is for the odd fields.

the polygon plane you are using is the height and width of your source footage and the height divisions are the same as your height resolution (this divides the UV space of the object into the resolution lines of the source footage). you select ever odd face of the polygon and apply the material for the odd fields then apply the even field material to the even faces.

after you apply the expression change to your scene it will deinterlace the footage since the odd fields are offset by one frame.

if you still don't understand i can make you a quick (much smaller) example.