I am trying to convert everything that is cyan in a pdf to black but keeping the screen values consistent eg. 80% cyan to 80% black, 45% cyan to 45% black. I downloaded a trial version of pdf toolbox 4 and got the screened backgrounds and type to convert but it does not do the images. Most of the images are indexed CMYK 1 channel but I have a few that are not indexed but are CMYK. Help please. Time is of the essence. Thanks