Smoothing Scans in zbrush problem

#1

Hello, im having problems smoothing scanned meshes in zbrush, im new to zbrush. I have some scanned mesh and the surface is bumpy, noisy etc. The mesh has around 1,5-5 milion faces for example. When i try to use any smoothing brush in zbrush (like smooth, smooth peaks, smooth valleys etc.), and even increase the size of the brush or intensity of the brush, the smoothing is very subtle, very very, its not usuable for me. One workaround i found out is to zremesh the mesh into lower polygon count (only few thousand), then SUBDIVIDE it (original scan mesh of course has only one subdivision level, with few milion faces). Then i project the original mesh to the zremeshed and subdivided one.

And then i can go to lower subvidision levels (which is not possible on the original scan) and can smooth the mesh quite ok, the lower the subdivision level i am on, the better the smoothing…

Im quite new to zbrush so im not sure if this is ok, i thought i should be able to smooth the original mesh with only 1 subdivison level quite well? I was not aware i have to go to lower subdivision level to smooth the bigger bumps/noise. The bigger the noise/bumps, the smaller the subdivision level i have to perform the smoothing on in order to get useable results…

Is this correct workflow? I want to smooth the original scans aswell is there a way?

#2

You have the right idea: retop>project

As for the smooth brush. The brush is averaging the distance between verts so obviously the higher the sub-divs, the more verts, the less smoothing will affect the surface.

If you open lightbox(hotkey is comma) in the brushes folder there is a smooth brush sub-folder with a selection of specialised smooth brushes. In there you will find a ‘smooth stronger’ brush. You can guess what this one does…:slight_smile:

Also, a very handy tip about smoothing in ZB: if you let go of shift whilst smoothing this will activate the alternate smooth brush. This magical brush will actually smooth out poles on the mesh.

#3

try this macro http://forums.cgsociety.org/showthread.php?f=140&t=1249246
once done go to the lowest subdivision level or near the lowest level and under tool>deformation> relax
all so try some of the polish setting.

the lower the polygon count the faster and easier it will smooth out.

#4

wow, this should be usefull, thanks guys, if anybody else has some tips, please write them also, thanks a lot! :slight_smile:

#5

Thanks the “Smooth stronger” brush helped, but the shift doesnt seem to be working for me, when i release shift, the smoothing just stops, dont you know what im doing wrong? (zbrush 4r6), windows 7 64 bit, no preferences of shorcuts changed in zbrush…

#6

when you let off the shift key and it stops then my guess is your polygon mesh is still to high.
the macro i posted try and smooth your mesh with the same method with the subdivision slider at 1 then try subd 2 then try subd 3 and see.
while smoothing and you let off the shift key its called smart smoothing see here
http://forums.cgsociety.org/showthread.php?t=1071877
you can think of smart smoothing as smoothing the problem area with out damaging your original mesh

#7

Whenever I’m smoothing noisy scan data in ZB, I tend to use the hPolish and TrimDynamic brushes. They work really well on dense geometry and when used in conjunction with the standard smooth brushes you can clean things up pretty quickly.

Depending on the type of object you’ve scanned, it could be worth looking at the Clay Polish option(s) under the Geometry rollout. For certain objects this works like an absolute charm, but as it’s an automated process, it can wipe out certain details so isn’t always the best option.

#8

here is one i did off of a scan image DAVID-Angel_OBJ.zip (5.2 mb)
http://www.david-3d.com/en/support/downloads
i did most of it threw deformation relax and polish and used the smooth brush for touch up,
didn’t take long at all, mask/blur the area’s you don’t want effected, you can all so set a morph for it in-case you over smooth a area then use the morph brush to bring the original shape back.
i all so ZRemeshed it