What is the workflow when using Subsurf? My question is what is the best approach to model an object for a realistic cinematic render when using a Subsurf modifier? Because if I may compare Blender to Photoshop, which uses layers, here all we do is not reversible. Even for the "Add Modifier", I need to apply it before moving to the next step. So for example, if I use the Subsurf, what is the best workflow if I want a realistic look? Do I need to push the values to their maximum (view=6+). What is your advice based on your experience?

Here an image to illustrate what I mean:



This sphere is perfect for me but the view (as shown on the image) is at 6. Broadly my question is how do you work? What is your workflow? Do you work with the shading smooth or keep the mesh with polygons to  modeling hard surfaces of your object and only at the end you turn your object into the final rendering with a smooth shading before applying the skin, colors etc.?
Looking at the sphere i see things go wrong.

Your viewport subdivision is set to 6
while your render viewport is set to 2 
Normally render is set higher then viewport, so i guess you saw to many facets thus... i'm thinking why.

More is wrong, your highly subsurfing a sphere why ?.
Go te edit mode, select all faces, go to shading/UV make sure to set faces to smooth. now the most simple sphere with a subdiv of 2 or 3 is likely enough.