When you convert illumination, shadow, shading, and textures to a file texture, you are performing a render; the process draws on the settings in Texture Baking Settings (see Texture Baking Settings window). Be sure you set these settings to achieve the result you want.
Use this procedure when you map a procedural texture or shading network to a surface and want to change it to a file texture.
To find out more about file textures in general, see Procedural textures.
For more information on the difference between converting and baking, see Baking illumination and color.
To convert a procedural texture or shading network into a File texture
The selected map output types are saved to disk.