Tip: Always use a picture with a significant size. I like to use pictures with at least 1600 px width and 1200 in height. This increases you chances of ending up with a result of decent quality.
For this tutorial, I have used Adobe Photoshop CS4 and the following base image:
This VW Golf GTD has got a smaller wheel size than it's petrol-powered brother, which is a pity, really. So, time to scale up those rims!
1. Open the image
2. Create a new layer by selecting New Layer on the bottom right corner of the screen. This should create Layer 1:
3. click on layer Background and press P to activate the Pen Tool. Zoom in with the navigator to enlarge the area of the left rear wheel (the wheel in the foreground). In the top left of the screen, click the small button called "Paths" to ensure working the Pen Tool does not fill in the area you are selecting. Click and drag around the wheel, and ensure you include a strip of the tyre as well. This will create a realistic blend later on in the process. The Pen Tool might require some getting used to, take your time!
When you have made a nice path around the wheel, click on the picture with the right mouse-button and select "Make selection". Take the default settings and click "Ok":
4. Press CTRL + C to copy the selection or go to Edit -> Copy. Select Layer 1 in the bottom right LAYERS window and press CTRL + V to paste the selection into Layer 1:
5. Go to Edit -> Transform -> Scale:
6. Press and hold Shift and Alt button to ensure the wheel scales from the center outwards. Click on one of the little scaling squares on the edge around the wheel and increase the wheel size. This is of course done to your own taste, but remember that enormous wheels and a little thread of rubber will not look realistic!
7. After scaling the wheel, click on the V (accept) button in the top right corner of the screen to accept the scaling change. Now hover the mouse pointer over the small layer thumbnail, press and hold CTRL and click. This will activate a selection around the area in the layer:
8. After the selection has been activated (you will see a dotted line indicating the selected area), go to Select -> Modify -> Feather... to slightly blur the edge of the selection box. Use 1 or 2 px when prompted. Invert the selection by hiting CTRL + Shift + i. Then press delete to remove a small fragment of pixels around the edge of the wheel. De-select by hitting CTRL + D and you're done!
9. Repeat these steps to the other wheels that need increasing. Try to match the wheel sizes to prevent the end result from looking off. I understand that the wheels on the far side of the car, of which we can only see the insides, need increasing as well. This requires some more skills like being able to remove a part of the layer. It is not covered in this tutorial.
After you have increased the other wheels' size as well, this could be the end result:
Hope you enjoyed this tutorial! Good luck!
