http://www.painters-online.co.uk artistFebruary 2021 21
PRACTICAL
TA w
Gouache versus acrylic
Although they are both essentially
opaque media, gouache and acrylic
have many differences. Acrylic paint
is more durable, the dried paint is
waterproof and very stable, so can’t
be rewetted and reworked, other
than over-painting. Gouache is more
forgiving and can be reactivated to
make adjustments. Acrylics can be
painted on many surfaces, including
paper, wood, glass and plastic. Gouache
is best suited for painting on paper or
primed card.
Acrylic, unlike gouache, can be
applied very thickly, with brushes and
other tools, to produce heavily-textured
surfaces. Gouache is typically only
applied with a paintbrush to produce a
smooth surface.
Basic materials
I recommend starting with just a few,
mainly primary colours, such as the
Winsor & Newton starter set used for my
demonstration painting (pages 22-23).
This will enable you to mix a fairly wide
range of hues.
I use the same brushes as I do for
watercolour, plus a couple of flats.
There is no need to waste money on
expensive brushes such as sables for
gouache. I can recommend Escoda
Perla Nos. 6, 8, 10 and 12 rounds, a No.
2 Pro Arte Acrylix rigger and a couple of
inexpensive flats.
Gouache works well on watercolour
paper of reasonable quality, providing
it is at least 140lb (300gsm) in weight.
Thick drawing paper, or a good-quality
card can also be used; I have also used
the reverse side of scraps of mount
board. When using card or mount board
I always prime both sides with a coat of
acrylic white primer. Occasionally, I will
use a medium texture paste to provide
a little tooth, which adds interest to
the paint surface and enhances the
brushwork.
I use three or four ceramic mixing
palettes but old plates work very well.
Try to use ceramic mixing areas rather
than plastic, as they are far superior.
Additionally you’ll need a pencil, eraser,
paper towel and, of course, water.
Techniques
Here are just a few of the many options
available to you. As always, you will
discover your own way of getting the
best out of the medium.
Opaque layers: use without adding
much water to achieve a rich opaque
colour that covers anything underneath
it. If you want to allow some of the
underpainting to show through, try a
dry brush effect (see below). This will
be more effective if your paper has
a little texture/tooth. These opaque
layers can be built up in layers to add,
for instance, a mountain over a sky, a
building over the mountain, followed
by a tree or figure over parts of the
building.
Wet-on-wet: dampen your paper then
introduce wet gouache to achieve soft
shapes and blurred edges. Although
this method can be a little bit hit-
and-miss, with practice you will soon
improve your success rate.
Dry brushing: this allows you to add
texture to your painting. Simply pick
up some gouache paint either without
or with just a little water, then brush offROBERT’S TIPS FOR
USING GOUACHE
l Don’t use too much water in your
mixes.
l Use less water in each successive
layer of colour to lessen the chances
of disturbing the under layer.
l Use less pressure on the brush with
each layer. The lighter the touch, the
less the risk of disturbing the under
layers.
l Resist adding detail too early.
l Dried gouache colour is soluble with
water, so be careful not to splash or
accidentally drip water on to your
painting.
l Resist over-painting before the
previous layer is absolutely dry.
l Plan your composition meticulously
before you start. This will give you
the best chance of success.the surplus paint (use a scrap of paper
or paper towel). Quickly sweep the
brush across your painting to achieve a
hit-and-miss ragged brushmark. Practice
will enable you to obtain the desired
textural effects.
Scumbling: for a rougher, more
textured surface, use a large/medium-
sized flat to dry brush with a small
amount of undiluted colour. Pull the
brush over the surface; you will observe
random gaps in the stroke that let some
of the background colour show through,
creating texture. Different textural
effects can be made by increasing or
decreasing the pressure on the brush.
Adjusting and correction: one of the
most useful aspects of gouache is that
you can rework elements of a painting
very easily, such as softening a hard
edge by rewetting. Painting with gouache
One of the characteristics of gouache
is that it dries darker than the colour
applied to the painting. Achieving
the required colour quickly can be
challenging for the beginner but with
practice you will be able to adapt your
mixes accordingly.
I always tint or colour the surface I
work on. This is optional but I find it
unifies the entire painting and reduces
the number of small, unpainted areas of
white paper showing through. This tint
can be very diluted gouache or acrylic;
I prefer acrylic as it is stable and won’t
be disturbed by subsequent layers of
paint, but you must do what works best
for you.
Gouache is rarely used straight from
the tube but a little water is all that
is required. Generally, it needs to
remain opaque but fairly runny (not
uncontrollably so). When you dilute
gouache with water, you can apply it
as a wash that will dry opaque in most
cases. If the wash is very diluted and
painted over a strong, existing colour,
it may influence the colour, but will not
cover it up.
Do remember that gouache is water-
soluble and that when you paint over
an existing, dry layer you will disturb it,
which can result in muddy effects. To
reduce this, make sure your background
layer is completely dry, then place
the new colour as lightly as possible,
without the brush damaging the dried
colour.
To achieve details and lines, work over
opaque, dry, backgrounds. To achieve
the most effective results, a dark/detail
line laid over a light background, or
the reverse, will work best. Similarly,
complementary colours, or warm and
cool combinations will be effective, too.p In the Deep, gouache on mount board,
primed with ivory black acrylic background,
19¼ 3 15½in (49 3 39cm)