I'm trying to create a texture for a sphere right now. With different Blender tutorials I get a texture on the sphere, but always with distortion at the north and south pole. I use Paint.net to create my textures, but I can't create spherical textures with it. Does anyone have a tool that converts a normal texture into a spherical texture?
Since normal UV mapping creates distortions (from the vertex linear interpolation) the Generated UV coordinates usually gives better result.
Give the texture node the Generated UV coordinates and set the method to project to Sphere.
Here is a full tutorial: https://www.blenderguru.com/tutorials/earth-cycles
Well, through UV mapping (it sounds intimidating but it's not THAT bad.) You can make a spherical object Much easier to texture, In edit mode, select edges on the "back"(or in this case probably the bottom) of the sphere going from the center STRAIGHT outward so you get an X or + shape that is equal on all points, hit CTRL+E to bring up the edges menu, select the option "Make Seam" then hit U to unwrap, that will leave your UV map with a Four pedaled flower shape.
If you simply need to paint something on a sphere (you've mentioned using Paint.NET), you can use Tintaur (an iPhone/iPad app) to paint directly on a sphere and export ready to use textures from that app. Here's a short video on how to do this