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.
Below you can see how the image looks so far. Still lots of work need to be done.
Step 3 - Blending the Sky
Before you'll start to adjusting contrast and colors of the sky let's focus on blending. Click on the layer SKY and change its Blending Mode on Multiply. You can find this option in the bottom part of the palette Layers (same as your layers). If you don't see it go to Window > Layers or simply press F7 on your keyboard.
Then lower the Opacity on 80% to get even better result. You can find this option right to Blending Mode changes on Layers palette.
Below you can see how the picture looks so far. It's much better but still needs some adjustments to look perfect.