Generating the Rust & Dirt Bump Map
For the rust and dirt bump, we will need to so a couple of more steps.
First, turn off all layers, EXCEPT THE RUSTY METAL & DIRT LAYERS. This will leave you with only these 2 layers showing.
Now select LAYER>FLATTEN IMAGE.
Next, select IMAGE>MODE>GRAYSCALE. This will convert the colour to a black & white image, which is what we want for our bump map.
Next, select IMAGE>ADJUSTMENTS>BRIGHTNESS & CONTRAST. Play around with the brightness and contrast sliders here until you get a nice contrast between the light and dark areas. This is my result of that process:
Now, as before, do a FILE>SAVE AS and save the file as Dirt_bump.jpg
The Finishing Touches
Now I assume everyone knows how to apply image textures in Blender, so I will not go into this here. If you do not, there are enough tutorials on that subject for you to look at, (go to Ingiebee's site for these ones). For myself, I just made a plane in Blender and applied the Colour map, Panel Bump map and then the Dirt Bump map, respectively. Added the lights and rendered the image. Play around with the NOR settings for both the Panel Bump and the Dirt Bump maps to get the desired effect that you want. This is my final result:
A better result can be seen here at my thread on www.elysiun.com -> Texture Test
As you can see, there are some steps required to generate decent textures. However, there is no getting around this if you want some realism or quality in your final rendered project.
I hope that this tutorial has helped you in some way and taught you something along the way.
If anyone finds any errors, or does not quite understand any of these steps, feel free to give me a personal message, (PM), at www.elysiun.com where my nick name is BgDM, or drop me an email at firstname.lastname@example.org
Thanks to adyus and hannibar for inspiring me to do this.
Derek Marsh (BgDM)