LANDSCAPE WITH MOUNTAINS WITH INCREASING GRADATION OF INTENSITY
Observing the landscape, Leonardo da Vinci realizes that the more distant mountains are, the clearer and less defined they appear.
This phenomenon is called aerial perspective and you too can easily observe it.
The cause of this phenomenon, as Leonardo already explains, is the presence of air between the eye of the observer and the object that is far away.
In fact, so many corpuscles are suspended in the air which, when hit by the light of the sun, reflect the light. The farther the object is, the more this diffuse light interferes with our eye .
The aerial perspective of the landscape in the painting Annunciation of the Virgin by Leonardo da Vinci
PREPARATION OF THE WORKSPACE
the sheet must be smaller than the media
it should be glued with the paper tape making a frame all around
the sheet should not be peeled off until the job it is finished and dry
Execution
To begin we prepare a sheet (a quarter of your rough drawing sheet is more than enough) glued to the support with paper-tape.
Prepare the diluted blue color (prepare a good amount so you don't have to do it again in the course of work)
Spread evenly across the paper and leave some white space for clouds only at the top of your sky.
Let it dry
Paint a mountain just below the clouds and work your way to the bottom of the paper.
Let it dry again.
Paint the second mountain (move the top a little so that it does not coincide with the previous one)
After letting it dry, proceed with the subsequent drafts.
As you can see, each draft appears a little more intense than the previous one: it is because the watercolor is transparent and each draft is added to the previous one.
ATTENTION!
When painting the different mountains, make sure that the top is always within the space already painted in the previous draft, otherwise your mountain will be 'cut' - one part will be lighter and another darker, ruining the final effect.
NOTE: How to tell when the sheet is dry enough to work on it again
Since this technique requires the use of a lot of water, it is normal for the sheet (especially if it is not watercolor paper of good thickness) to swell. It is precisely for this reason that before starting to paint we have to glue it to the support with a frame of paper tape all around.
When the sheet dries, it returns to spread out. Also, by touching the sheet with your hand, you should feel it no longer wet and cold.