Canon PIXMA printers guzzle ink in duplex mode
Canon’s PIXMA printers have a defective duplex mode. (Duplex is where you print on both sides of a page.)
Canon says that when using duplex mode, “grayscale will be created using a combination of the color (dye) inks to prevent smearing.” Even when you print black and white, the printer still approximates the black color using the color tanks.
This is stupid:
- Gratuitous waste. Color inks are expensive.
- Duplexing is slow. Color printing considerably slows printing.
- Poor quality. Approximating black with color inks produces a murky, greenish black, not a true black.
Summary: to prevent smearing, they make the printer use more ink. Does that make sense? Maybe if the goal is to sell more color ink cartridges!

[...] support days. My current printer, a Canon Pixma MP-970, is junk. Ink’s too pricey, and Canon rigged it to drink ink in duplex mode. Drivers feeling like a product rushed out before usability testing. After just 2 years old, prints [...]