When you have a white canvas any colour you paint onto it looks
drastically different because of the optical effects and tricks colour
plays on you.
As a beginner this can be disconcerting, for example, if you paint a light grey onto your white canvas it will look black.
With an untrained artistic eye it’s really hard to judge colours and
tones accurately because of the effects of ‘Simultaneous contrast.’
Heavy body paint will need more water than a soft body paint. As I use this technique on most of my paintings I use a fluid acrylic
from Golden paints. This has already been mixed in the factory to a
thin consistency and has a good level of acrylic binder in the paint and
a really nice strong saturation of colour. You can add a touch of water
into it and it will still hold the acrylic bond really nicely.
Some manufacturers recommend you
don’t dilute Acrylics with more than 40 – 50% water due to diluting
some of the acrylics adhesive qualities (as you are diluting the amount
of acrylic ‘binder’ in the mix). However,
for this stage of the painting this doesn’t matter, as we’re painting
directly onto the canvas. We want the paint to ‘grab’ onto the canvas
and soak it. If you mix in too much medium at this stage it can cause a
resist to the further layers of paint adhering onto them as easily. Keep
the mix thin and ‘lean’.
If you are finding the paint is pooling in small droplets on the
surface when you are just using water you need to add a dash of ‘flow release medium‘ to the paint. This will help to break down the surface tension and make the thin layer of paint soak into the canvas.