Tip of Day #9Today’s Tip of the Day is about Bump Maps.
More specifically, this is about how to determine what your bump map's strength should be. When you've got a textured material, I find it's easy to set the bump value too high or low.
1) In the material editor try turning off the texture maps and replacing the default black color swatches for something like a 50% gray (when you open the color picker there is, by default, a swatch for it in the top-left) before running a preview render. This will help you focus in on exactly what the bump is doing. I tend to find it most helpful to leave the specular layer ON which helps you better visualize/tweak that layer as well at the same time.
2) Use the Global Bump slot when possible (as of v2.5 the wizard doesn't use the Global Bump slot for some reason), it'll save you from changing bump values in 2 or more different spots.
3) Use the Store feature in the editor to store various bump values. In the image below you'll see the results of a value of 10, 20, and 30 (these values are pretty high since this particular bump map doesn't have much contrast). It makes it much easier to see the difference (to my eye, the correct bump may be something around 25ish if you're going for a new decking look.
http://dl.dropbox.com/u/384281/boards-01%20Bump.zip -Brodie