Now is time to jump into Photoshop where, with the use of photos, I make the texture feel more realistic. I used a photo of an animal skin blended on the texture map with a soft light layer. I used a photo of an animal skin pattern in order to give a pattern to the alien skin and then I used a photo of a tree's roots, blended on the texture map with a soft light layer. In order to understand the forms in Photoshop, I usually export an ambient occlusion map and a cavity map from ZBrush, which I overlay on top of the texture map in order to push the details of the sculpture more, and be able to read the map (Fig.06).
Then I composed my render passes in Photoshop, where the process was pretty fast, since I just had to blend my passes well with different layer blending properties. I usually use a Screen layer for the specular pass and rim light pass, a Soft Light or Multiply for my shadow pass and ambient occlusion pass, and a Soft Light for my texture pass, which I use in order to reinforce the look of my textures and make the details pop out more. Then I use some color correction in order to make the image a little bit more blue (Fig.07).
Since the final goal for this image was for it to be a concept, I couldn't spend time creating the texture for the eyes, so I just used a simple blinn shader for the eyeballs. In Photoshop I was able to blend a photo of a cat's eye on my renders with the use of Soft Light blending mode and some painting, in order to create the eyes for this creature (Fig.08).