Gimp has a built-in sphere mapping filter (Filters > Map > Map Object) and that works great for spherizing graphics. But for a chrome ball effect, a little tweaking is helpful.
Here’s a brief tutorial walking through the process of taking a photo and making a chrome ball from it.
To clarify upfront, you can create a chrome ball from scratch in GIMP by just using the Map Object filter as mentioned above. But using an image adds some nice variation to the ball that tends to look more realistic.
We’ll use this freely available image: https://en.wikipedia.org/wiki/Cabin_(ship)#/media/File:Vasa-great_cabin-2.jpg
Simply download and open the image (or your own image) in Gimp. Once it’s opened up, let’s resize the image so that it has a 1:1 aspect ratio.
We’ll blur the image a bit for the chrome effect. Go to Filters > Gaussian Blur… and set the blur to a radius of 30 for both Horizontal and Vertical.
We’ll use Gimp’s Map filter for the sphere effect. Go to Filters > Map > Map Object… and you’ll see a panel of options.
Tweaking the settings
The following are some of the settings that I found worked very well for the options in the various tabs.
- Map to: Sphere
- Transparent background (ticked)
- Create new image (ticked so you can easily try variations)
- Lightsource type: Point light
- Lightsource color: white
- X: 0.0
- Y: -30.0
- Z: 10.0
- Ambient: 0.3
- Diffuse: 0.75
- Diffuse: 0.3
- Specular: 2.0
- Highlight: 1.0
- X: 0.5
- Y: 0.5
- Z: .095
With the settings configured the way you like, just press OK to proceed. It’ll take just a moment to process.
And here’s the result with the above settings, a beautiful chrome ball with subtle photo content.
Please feel free to post some results here. I’d love to see them. 🙂