Hi again Matt,
I couldn't add these images to the first post so had to start a new one.
If you look at the 2 images you might see the problem i'm having.
The image that is red you can see a very thin boarder around the edge which is the soft edge of the mask which i have chromakeyed out and on the other image which is more or less white/grey it's not such a problem due to the image being more or less the same colour or white.
I don't think the white soft edge is going to be acceptable...
I've tried using the coarse/med/soft chromakey all of which still give the white boarder....the only other way i can think of is taking a picture of the actual projection screen when its made with a black or coloured backround and trying to use that as that as the mask and applying the same process of chromakeying it out.
Any further suggestions appreciated
Regards Cormac
