Exporting round objects for 3D printing

Hi, Guys!

I often build things for 3D printing - they are also available here - so a question just came to my mind. Stl is the most famous 3D printing format, but as far as i am concerned it is a polygon mesh that gets exported. For me that means, that, if I export a round object like a sphere, the mesh has to be very detailed to look good as a printed object then. Unfortunately, a nicely exported .stl sphere has some MBs then - but it's a simple sphere.

Does anyone know if there were file formats which export round objects better e.g. with curves and not with ploygons? That would be a way better solution for exporting objects for 3D printing in many cases!

Thanks and regards,

Christoph