Exactly what good does the Poser Subdivision feature do in Poser? Does anybody even use it?

Most obviously, the first thing that comes to mind is that it can breath new life into some low poly props or figures, which probably don't look so great rendered closely, especially with the new IDL lighting.  As long as the model was built using mostly quads, the subD will do a nice job giving it more geometric fidelity in close-ups, or giving you more surface topology to use the new morphing brushes.  Someone could easily use it to smooth areas they need for morphing some details, without having to export out to zbrush or the like.

same as the sub-d mod in blender does

it increases the face and poly count

it makes low poly good meshes and makes them more useable and kills bad meshes quickly

Makes a big difference to some transmapped hair for close ups.

It gives me better results when assigning high-res displacement maps with large displacement values, to (relatively) low-res meshes.

Why are you asking btw?

1. It smooths a figure's mesh (DUH) :-)

2. It can enhance rigging by smoothing folds mesh deformation. But it is not a replacement for proper weightmap editing or JCMs.

Subdivided Posette's joints look a wee bit smoother than unsubdivided Posette's joints, but they still don't look even remotely as good as Vicky 6's joints. For that you'd need a dozend JCM's and couple hours of weightmapping work.

1. It will not give you more editable mesh. Only Studio's HD tech can do that. But you might be able to do more extreme morphs now as the smoothing is enhanced.

2. It makes rigging faster as you only have to rig the low res cage.

3. It can lead to artefacts or unwanted mesh creasing depending on the figure's topology.

And yes, I use it all the time for my Genesis based figures. It also works great on lower res hair that is constructed from strands.

But like Poser's old "smoothing" feature, it really depends on the mesh topology if and how well it can be used.

Just a side note.

Posers SubD is pretty strikt.

Not all meshes survive Posers SubD.

You can SubD a mesh in Blender and the same mesh would fail a Poser SubD.
So , you have to build carefully and check a lot in between.

But to answer your question; YES Poser SubD is widely usable and used.

Great help with dynamic cloth in the cloth room. You can have a model that simulates quickly and have it look good in the render.

@PhilC: true, but be aware that a fine-mesh cloth has a different dynamic behavior from a more coarse-mesh cloth: the fine one behaves as thinner material. So a T-shirt with thick edges should have the fine mesh inside and the coarse mesh at the edges (people tend to make their meshes just the other way around, as more verts suggests more material. That's not how cloth sims work).

Quote - @PhilC: true, but be aware that a fine-mesh cloth has a different dynamic behavior from a more coarse-mesh cloth: the fine one behaves as thinner material. So a T-shirt with thick edges should have the fine mesh inside and the coarse mesh at the edges (people tend to make their meshes just the other way around, as more verts suggests more material. That's not how cloth sims work).

That's right, and should be the same in any cloth simulation system.  If you were to simply subdivide a simulated low poly mesh, the cloth behavior would still represent the low poly version, not the subdivided version.  This might be fine for stills, but if the goal is animation, the result will look potentially unnatural and stiff.

Yes it will not work in every case but it is an option that has worked for me a number of times and I just wanted to pass on the tip.

If you find it helpful, great, if not then no worries.

I noticed when subdividing in Poser that the uvmap and textures can have minor differences in results. The rounding from the subD rounds the mesh but the uvmap/texture will stay the same offcourse. If you look close enough you can see the color of the texture outside the uvtemplate can peak through. Eventhough you use an UV map with a four pixel overlap.

so if you see like a tiny spot black, it's because of the rounding in the subD not because of a faulty texture.

But as the spot is so tiny it's easy postworked in Photoshop if you have a super closeup render that is.

Quote - Exactly what good does the Poser Subdivision feature do in Poser? Does anybody even use it?

Games don't use SubD's & quads they use normal maps & Tri's.

Every one Max,Maya,C4D,LW etc etc has used SubD meshes for 20 years.
SubD meshes are modeled & texured to be SubD'ed.
The rule is model 100% quads.

Thats why V5,V6 ,Rox's are modeled the way they are.
back in the day V4 was modeled to work in Poser & fussion to be SubDed in fussioned app's
but we did not like her high polycount.

Dawns modeled to work in older Posers and to be SubDed also.

but any of the older meshes not modeled to be SubDed .results may very with SubD.

... the final render with a subD ( Catmull clark Ngon), modifier on just the jacket garment.