Digital BW, The Print

Here is some more data. I just sent an RGB file to the ABW driver 
rather than my previously used greyscale and the "tint" of the image is 
still different than my 8x10 work print. So what has changed? Well I 
went up a size in EPSG paper from 8.5x11 to 13x19. So, can different 
batches of paper make a difference? I have also changed some of the ink 
cartridges recently (all K3 inks). My bigger prints look colder and 
greener. So I wil reprint one of the images in the small size to see if 
anything has changed. If so, then ink batches may make a difference. If 
not, then paper batches may make a difference. Thoughts????