For some time I have been using "compatible" printer cartridges.
Everything I print in colour has been less and less well rendered over time, to the point where everything had an unpleasant blueish tinge.
It was time to splash out on some genuine Canon printer cartridges and see what that does.
And I am happy to say that the results are positive. We have yellows, reds and greens once more!
Now I need to stock up on paper.