I am stacking 2 Christie roadster 20k's In a 4 projector blend using a barco encore video processor and a MacBook Pro via a matrix dual head DVI. Using the encores test raster I have converged the projectors but when I switch to the MacBook the lower projectors image is misaligned only on the left hand side of the image. It looks like the image is warped but all warping is disabled. Plus I can't get my head around how the test raster does not have the same issue... I have only a few hours to fix this before tomorrow's show. Everyone I have spoke to about this is just as stumped as I. I am now going to try generating the test grid from the MacBook in hopes that will allow me to go around the problem but I won't be able to sleep if I don't understand how this was possible in the first place! Please help is you can.