ACRYLIC versus WATER COLOUR or OIL PAINT
I wrote a blog piece about oils, acrylics and watercolour paints about a year ago. [LINK]. The subject came up again recently when I was explaining my ‘acrylograph’ technique. That is where I paint over a canvas print with acrylic paint adding extra detail and texture. [LINK]
The crucial point that came up was that acrylic paints are water based. And they dry quickly. Within a couple of hours usually. They mix with water when wet, but when dry acrylics are no longer soluble. They are fixed.
Whereas watercolour artists know that if they re-wet the paint on a dry area then the under-paint will soften and bleed into any top layer. You can blend new paint onto old paint. You can soften edges with a brush of water only.
Within some restrictions you can do the same with oil paint as long as you don’t leave it too long. Oil paint mixes with turpentine or turps-substitute for instance. It dries much much slower. That is great if you paint pictures where you want to be able to work on yesterdays paint as well as todays.
But you can’t do that with acrylic. Once it is dry it is fixed. So you have to think about layers of paint in a different way.
That difference between ‘fixed’ and ‘not fixed’ is a major factor.
SCUMBLE AND GLAZE PAINTING OVER UNDER-COLOUR
If the under-colour is important then it can still add to the effect of the artwork. What an acrylic artist will do is paint over under-colour quite happily with transparency [glaze] or broken texture [scumble].
Often transparency is achievable by just adding more water. Even quite opaque colours can be used if they are thinned down.
Another method is to paint over previous colour with quite dry opaque colour but with a textural technique that utilises the canvas or paper texture. I have used a roller to put top-colour over under-colour leaving under-colour visible. It can also be done with a dry brush technique.
Or scumble. Scumbling is where the top colour is scrubbed on and wiped off leaving top-colour in the hollows and under-colour on the higher levels.
It is much more difficult to do that with oil paint because the under-paint will probably still be a bit wet in the hollows and just mix and smear. Watercolour will just remix and so it won’t work at all.
So my use of acrylic paint over the years gave me the experience to know that I could use it to influence the look of an existing surface in several exciting top-coat over under-coat ways.
ACRYLIC OVER PAINTING ACRYLOGRAPHS
Then along came giclee printing on paper and then on canvas. In the beginning we used it to make reproduction prints of existing finished artworks. I got my own kit so that I could self-publish prints of my work.
When I noticed that some canvas giclee prints looked dull and flat I tried painting over with acrylic varnish instead of the recommended spray sealant.
I could paint over a giclee print on canvas with textural varnish as well. I tried adding acrylic colour and experimented with the over-painting acrylic techniques previously learned in my painting studio. Wow again!
This is possible because acrylic paints are not watercolour or oil paints. Watercolour is too delicate and is not permanent. It is just wrong. Whereas oil paint could be used over a giclee canvas I guess. But not over a giclee on paper because the oil content would bleed sideways and muck up any clean or clear sections. Come to think of course that must be happening on a canvas as well. So oil paints onto giclee canvases is probably wrong as well.
More recently I have realized how important the under-painting in a giclee print on canvas can be as well. This is because I can use all sorts of creative effects on my computer screen before I print the canvas giclee. I can foresee the canvas basics. I can experiment widely and wildly. I can anticipate the canvas giclee as a base for the subsequent acrylic top-coats.
Acrylic paint and acrylic paint techniques are just right for overpainting a giclee print on canvas. That is how I make ‘acrylographs’.
Onward and upward. We live in exciting times!