Dyeing sailing canvas in the age of sail

How difficult was it to dye sailing canvas, and how long would the colour last at sea?

Dyeing canvas was relatively easy, and properly dyed sails could retain colour for quite a while.

Canvas could be dyed with different dyes or made in the desired colour from the outset. Properly dyed sails could keep their colour for quite a while at sea. Work on the canvas produced a variety of sail colours. Hull colours also varied, so a fleet should not be imagined as a homogeneous block of colour.