Figure 4.5 - Subdivision settings
What will determine the smoothness of your model is a combination of
the subdivision count and algorithm. At the top, you will see two
smoothing algorithms:
Catmull-Clark: If you want a full smoothing of your model with
rounded shapes, you should use this method.
Simple: For projects where you want only new faces and divisions
but no smoothing, you can use the simple option.
The level of subdivisions shows unique values for smoothing objects in
the Viewport and Render. Usually, you will use a lower value for the
Viewport and a higher level for the Render. The reason is that a model
with a high level of subdivisions may add a significant computational
load to your system.
With a high level or subdivisions, you might experience some common
operations delays like changing the zoom and even swapping between
Object and Edit Modes. Depending on the value and number of
smoothed objects, you can even crash Blender.
A value of two for the 3D Viewport and three for Render usually shows
great results for most 3D Models. Unless you have a project requiring
more subdivisions, always use two for the viewport and three for render.
In Figure 4.6, you can see the difference between using one and three
for subdivisions.