1. Create new document (File - New , 500 to 500 pixel 72 dpi, Mode: RGB Color, Contents: white)
Now give your background Layer (Layer name=Background) a new color. Choose color CC9966 and fill your document with the Paint Bucket Tool . We only need this layer.
2. First we will create some plain metal. Go to Filter - Noise - Add Noice and use the settings shown on the right (2).
3. Now go to Filter - Stylize - Wind and apply the plain wind effect. Repeat this step 3 more times. (Watch the result on the right, part 1) After that here comes the somewhat tricky part.
Take the Burn Tool and paint over the texture. In order that it looks realistic use more than one presets. In this case I used two. I draw 4 lines with (Brush: 60 , Range: Midtones , Exposure: 85%) and about 2 to 3 times with (Brush: 17 , Range: Midtones , Exposure: 85%)
4. Now go to Filter - Artistic - Sponge and apply this Filter with Brush Size=9 , Definition=11 , Smoothness=1.
5. Now remember our intention. We wanted to create some realistic rust textures. Rust in fact has no plain color. It's ugly wasted up with a several colors and sub colors. For that reasons go to Layer - Duplicate Layer (call this layer Emboss) and apply the Emboss Filter (Filter - Stylize - Emboss) and use the settings on the right. Furthermore apply once again Wind Filter. (Filter - Stylize - Wind, Method= Stagger)
6. Now that looks like rust! In order to perfect this texture again copy the first Layer (name= Background) and call the new layer "High Pass". Go to Filter - Other - High Pass and apply this filter with Radius 71. After that go to Filter - Stylize - Emboss and use the settings shown on the right.
7. Finally we have three Layers. Layer Background, Layer Emboss and Layer High Pass. Now we will Blend those layers together. Use Blending Mode "Hard Light" for both layers above the Background Layer. Safe your document (File-Save for web) and you are ready. Of course you can experiment with the Blending options. You will see that there are plenty of possibilities how your rust texture could look like.
8. It is useful to add new textures to your Layer Styles. That means open the document you just saved. Go to Edit - Define Pattern.
9. In order to apply your texture there are several ways to do that. Open a document (a document you want to make rusty) of your choice. Create a new Layer above the first layer (Layer - New - New Layer). Take the Paint Bucket Tool and switch the Fill Options of the top of the page from Foreground to Pattern.
Choose your Rust Pattern and fill your document. Now switch the Blending mode to maybe Overlay and you are ready.
10. The second method to blend pattern in pictures is to use the Layer Style Engine. Go to (Layer - Layer Styles - Pattern Overlay) and use the settings on the right.
Your are done. I hope you enjoyed this tutorial. Below you see my final result . In this case I blended the generated texture into an eye.
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