This image was for a CG exhibition, named "Industrial Impression: Design & Creation Exhibition". I used a lot of industrial elements as fodder for the creation of this image. The purpose was to show the relationship between the development of post-modern industry and the human way of life. There wasn't any clear intention at the start of my creation process, I just blocked in some shapes at random. Then I gathered the interesting parts of them and ultimately created a final concert composition (Fig.01).
To make sure the sketch layer was complete before adding color, I looked at pictures of some industrial materials and then blended them into the image. The aim was to keep the style and design bold and interesting, but to also try and maintain the feel of the scene. I then added more details as I adjusted the composition. As you can see from the sketch, everything in the distance looks lighter and the colors are stronger in the foreground. This gave a good sense of depth (Fig.02).
I then selected a large brush to add color to the image in a single layer. I set the brush mode to Multiply and then selected warm colors to paint on it. Multiply mode allows color to be added to the sketch transparently, and will not cover the original sketch layer. It is a commonly used color method, but do not select dark colors or paint over it repeatedly. If you paint in Multiply mode with darker colors repeatedly in one place, it will make the image black. Making the image a little darker can enhance the tone of image and also offer a nice base tone for adding all kinds of highlights later (Fig.03).
With a basic color set I then began to paint in the details. I started with the tones in the distance. I tried to keep the tone and colors consistent with those in the previous sketch and the strength of the color in the distance low. To do this I decreased the color's saturation. I also kept the whole image in warm tones, making sure there wasn't too much contrast, and made sure that the only light in the scene was diffused (Fig.04).