"He who marches out of step hears another drum." ~ Ken Kesey
I'm a little confused, a bitmap mode in PS is black and white, no grays to print as a halftone. We always save the file and print from Illustrator (I'm pretty sure CD does the same, but I don't use it, just assuming). Are you converting a grayscale image to bitmap using the halftone function to make dots? If so, then like others have pointed out, the white isn't 0%, but something higher... post an image if you have a chance...Steve
unfortunately can't post an image, it's protected/paid property.
If you are used to Corel, why don't you just import the PS file and print from there?
If it's greyscale, try converting to Multi channel and printing that way. Sometimes just switching modes will work.