Everything except the sky is rendered by hand on scratchboard. The scratchboard art is then scanned at 1200ppi in 1-bit.

The line work for the sky is added with PhotoShop. For more information on using PhotoShop to make line work see, "Digital Video Frame To A Woodcut Icon."

See details of the PhotoShop sky painted in (Grayscale, and then converted to Line Art).

Tip:
When painting a Grayscale image that is to be converted to line art (to look like a line drawing), drastically exaggerate the detail and contrast.