How to use subdivision on simple object?

I ve been trying to use a simple quarter ball in a project. Using subdivison under smooth mesh results i a rather like pillow looking mesh. Not using subdivision results in a blocky looking mesh. I can i solve this ?
Zwischenablage02

That’s how Subdivision Smooth works in any app - subdivide and smooth sharp edges. Outcome would depend on the quality of topology.

CC does not have a method to keep sharp edges intact while subdividing, so you need to do it in Blender using Edge Crease for selected edges while applying Subdivision Surface modifier.

(on the left segment subdivided in Blender with Edge Crease applied to outer edges)

Untitled-1

I thought so, Thanks much for the hint, finally did it in Blender using IIRC edge Split and Surface subdivision modifiers . Looks kind of smooth now.
Zwischenablage02

I would not recommend Edge Split modifier in this case. It modifies topology doubling vertices at sharp edges. And as far as I can see you may already have an issue there with it. There probably is a hole at those slightly rounded corners.

Marking edges with Edge Crease does nothing to the topology and just keep them intact during subdivision.