Turn any photo into a dot grid artwork with these Photoshop actions. You'll get great results with dots that change size. They get larger in brighter areas and smaller in darker areas. Free download available.
I used Hue/Saturation to correct the color of some leaves on the right of the ground and add more cyan to the scene:
On this layer mask use a soft black brush to erase the parts we don't want to be affected in this step:
Final step: Make a new layer with the same settings in the step 33 but uncheck Clipping Mask option. Use the Dodge Tool to brighten the trees on the left edge as they need more light.