Here is the background to my Naplopomo badge posted yesterday.
It is a little exercise that is great for demonstrating the effect on a painting of different grounds, or background colours.
The brief is to divide the work into four and have four different grounds as follows:
1. (top left) white gesso
2. (top right) any very dark colour (a 'black' mixed from other colours)
3. (lower left) any colour
4. (lower right) the complement (opposite on the colour wheel) of (3)
Here are the grapes I used for my subject. As you can see, they became rather wizened towards the end. I had to use my imagination to plumpen them up again. And a photo or two helped too.
The still life was worked on each of the four different grounds, but using the same palette for each.
I worked in acrylics on a piece of unstretched canvas 560cm x 560 cm. I painted on each bunch of grapes at the same time, adding a colour/ developing a feature to each square in rotation. Towards the end the differences between the squares was very marked. Especially noticeable was the yellow square- In this one the grapes were very brown. I confess I cheated a bit and added a lot more blue-violet to this one. Even so, the differences in atmosphere were still very apparent on completion.
You can see very clearly how the tone of the ground influences the subsequent layers. It's important to choose a ground that helps create the mood you want in your painting.