http://www.artrage.com/artrage-studiopro-features.html ... right at the bottom of that page they give file format info. If anyone is really interested I'd suggest walking about the site to see what's what. But basically, after its own file format (PTG), which saves everything including paint thickness, it can import/export to PSD which keeps all the layer info and blending modes, and PNG, JPG, TIFF, BMP, and others "depending on your operating system."

