WHAT IS GESSO?Gesso is a primer. Artists sometimes apply it to a surface before painting on it. In fact, gesso looks a lot like paint.
Originally, gesso only came in white. Artists put it on canvas, wood, or other surfaces before creating a painting with oil paint or acrylics.
Gesso makes the surface a little stiffer. It prevents paint from soaking into the support (canvas, paper, wood, etc.), and it gives the surface a little more texture (called "tooth"), so the paint sticks better.
Today, gesso comes in many colors. White is still the most popular, but black and colors are also widely used.
Recently, I have been painting with oils on canvas. I painted gesso over a few old oil paintings. Having seen paintings with texture, I decided to create even more texture by applying the gesso with a palette knife.
A couple days later, feeling dry to the touch, I painted the cedar tree and its boughs that I see outside my window on the textured, gesso canvas.
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Look closely, you will notice that the tree trunk has interesting texture which I was excited about. BUT, the next day certain areas where the paint was applied heavily with a palette knife began cracking.
QUESTION:What caused the cracking?
The cracking does not reflect the shape of palette knife strokes.
It is selective; both in areas of thick and thin paint.
The gesso felt dry.
Ideas, anyone?