Brush, Under Painting and Yosemite Study

I did two studies in class the other day with different under paintings. This is one where I used local color for the under painting.  It is a small 8X8 . I painted the sky with a blue under painting,  Half Dome was grey blue, the  pine trees in the light were orange and the dark were purple and green.  I painted the land mass in the sun transparent ocher and the shadow magenta with a touch of ocher.

I found the sky too dull so I used a palette knife with very light lemon yellow and then cerulean blue with a lot of white and knifed over it  without blending. I then added just a touch of very light pink.
I continued the painting using only a brush.   I lost the under painting to the tree because I changed the value and over painted.  I did manage to keep the beautiful under painting. on the land mass.  In shadow land mass, I put a few strokes of paint to dull down the bright magenta.

I think the pine trees and Half Dome are not different enough in value. I will need to lighten Half Dome without making it as light as the sky.