Predessor to the Pro-100

[mikling]

This little thing I stumbled across will explain the function of the gray inks in the Pro-100 and why it is used.
It's a bit technical but I think the essence of the matter is there



The above swatches shows us how a 6 color printer would mix the colors as opposed to a printer using grey inks. This will illustrate how the ink dots are placed in dot patterns to produce the same color that we see. You can distinctly see that the overall patterns in detail are different but will look similar to our eye zoomed out.

What is not shown is that the color shift or cast will not vary as much with the grey inks as opposed to when certain colors are highlighted. See that yellow dot in the bottom swatch. I imagine that yellow radiates nicely with a warm source and will tend to shift the color more.

 

[mikling]

The last paragraph is interesting as this is what distinguishes the Pro-100 from the Pro-9000. Remember the Pro-9000 was in reality for most papers a 6 color printer and the other two colors was only used when certain paper settings were used. For all others only six colors were used.

While we are not privy to the engineering details of Canon, an article on an older Hp printer gives us a clue as to what is going on behind the scenes. I expect the same reason was used in developing Epson K3 inks ( Again k3 being 3 Ks or 3 blacks/grays since Epson called their Gray light blacks)