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.
Create a group for the tree layers and add a Hue/Saturation adjustment layer to change the color of the trees.
Make a Curves adjustment layer and decrease the lightness. on this layer mask, use a soft black brush to reveal the light on top of the trees.
Create a Gradient Map adjustment layer on top of the layers and pick the colors #1b180b and #b30b0b. Lower the opacity of this layer to 20%.
Make a Color Balance adjustment layer and change the Midtones and Highlights settings:
Add a Selective Color adjustment layer and alter the Cyans and Magentas values:
Create a Curves adjustment layer to bring more light to the top middle of the scene. On this layer mask, paint on the rest to keep its lightness.
Make another Curves adjustment layer to increase the shadow for the corners of the canvas. Paint on the middle of the scene to reveal the light and make a nice contrast for the whole scene.