For the Gatehouse model illustrations, I started out by creating a blank, white Sketchup model which I then imported to Lightwave in order to position, light and render. Then I brought the white rendering into Photoshop where I apply the textures and text, using the rendering as a shadow guide. I also added a lot of hand-drawn elements, shadows and grunge. I often use this technique rather than creating and rendering a detailed, textured 3D model.