My autumn classes include colour theory and abstraction, and in the process I usually do a few spur of the moment drawing and paintings to demonstrate to students. This is a mini gallery of those examples from this autumn.
Before my colour theory class I held a class on composition, and one method I talk about is the framing of the focal point of the image with tone or colour. Above is a quick example where I put down blues first, then framed them with dark cliffs. Then I created a similar study where I put down blues then framed them with a surrounding light tone.
While showing the light tones, students wanted to know how I glaze colours. So I did some quick and dirty watery layers over a dark frame example I'd painted earlier. My "glazes" are acrylic with water and essentially like watercolour layers. (For beginners I highly recommend starting with a fluid acrylic medium and not water.)
Then I showed that similar layers of transparent paint can be done with colour as well as white - doing acrylic glazes of blues over a warm sienna shape.
These are all just example for students, about A5 in size, and not intended to be final paintings. Though I have an obsessive habit of making them into landscapes!