We had a job going to our Canon ImagePRESS C10000VP and the PDF was using transparency on a background photo which has knockout type on top. I flattened the transparency, and the type appears heavier in spots; under a loup it looks to be spreading in areas where the background has more screen. Could the flattening have something to do with that? The only difference between the original PDF and mine is flattening; on screen the flattened background is slightly darker than the non-flattened one, but the type appears identical.