Ink is a way of darkening colours, usually it is painted on and it runs into the cracks and deeper parts of the model - giving it shading. Though it can be added to normal paint to enrich the shade and deepness of the colour.
But washing..
An ink wash is basically watered down ink. How do you do this? Simple, add water to the ink. Place some ink on your pallete and then add a few drops of wate, this will make the ink thinner. Often the thinner the better but it depends upon the model/section in question - you decide. Then get some on your brush, don't load it full as this can lead to too much ink on the model and then apply it to the model. It should flow into the cracks, creavaces and such giving shading.
The more water you add the thinner the ink and the more layers needed to make it look like it's there.
KU
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