Vampire Head

Discussion in 'Design and Modeling' started by JBoskma, Aug 4, 2008.

  1. JBoskma
    JBoskma New Member
    Hi guys, thanks for letting me in on the beta! I am very excited about this project you are setting up.

    I can't wait to actually start miling out some of my work, but I am a little uncertain wether or not my work is suitable for 3D printing or not.
    I've got this vampire bust sculpt, which I want to adjust slightly, making it sit on a pedestal. I will have to reproject the detail onto a new watertight mesh, but before I do so, I want to check a couple of things. I hope you can help me out! :)

    - The model is currently sitting at 1,3 milion Triangles. This will likely increase once I've reprojected the displacement detail onto a watertight basemesh.. I presume the final model will be around 2 milion polygons. Will the Shapeways software be able to handle this?

    - Preserving as much detail as possible, how big would you advice me to print this model and in which output material?

    - Is there a chance you can give me a rough idea of how much of the detail will be vissible once printed in the best possible conditions?

    Any tips you can give me, will be most welcome! Thanks for your time.

    The model:
    Additional shots:
    Last edited: Aug 4, 2008
  2. bartv
    bartv New Member
    Impressive! Was that done in Zbrush?

    Our server is currently scaled for models of 100k-500k triangles, so 1M-2M is bound to crash something ;)

    Is is an option to use less triangles in areas with little detail and use high-density meshes only where you really need to?

    We can print details of about .5mm with the 'Detail' materials. If you're worried about that, then it might be a good idea to print a small test sample first, maybe with a few regions of varying mesh density. From that you'd be able to tell:

    1. how good the print result will be
    2. what a good resolution for your mesh would be.

    Oh, and when preparing to print, don't forget to make the model hollow! That'll save you quite a few bucks.


  3. JBoskma
    JBoskma New Member

    Thanks for your quick reply. Model was sculpted in Zbrush indeed.

    Too bad your server is capped at 500k, are you guys planning to work on that? I know a whole lot of folks that would love to have their zbrush / mudbox work printed. Most of those models easily pass 1-2 milion triangles.

    The way Zbrush works, is that you start with a fairly low res mesh, about 3000 triangles for this guy, and you keep subdividing the mesh to add smaller form and detail. To add detail in only certain areas would mean you'd have to seperate the model up into pieces as well, and I guess that would open a whole bunch of other problems when outputting it in 3D. Especially when you are working with different levels of subdivisions for the final version.
    I suppose cutting the model up in tactical places and do multiple prints, is a way to work around this though.

    A friend of mine, who's currently working at Stan Winston's down in Hollywood, recently showed a great example of detailed 3D printwork based on ZBrush data. His work on Indiana Jones and the Kingdon of the Crystal Skull made for an excellent 3D print. I am fairly certain his original model was constructed out of more the 500k polygons. This is a perfect example of the type of print quality I am looking for, have a look. page=1&pp=15
    When you take a close look at the profile shot of the 3D print, you can clearly see a seam there. I am thinking they may have done two seperate prints and brought those back together afterwards as well. What do you think?

    When hollowing out a model, you do mean giving the current model thickness and have an inside set of faces with their normals faced inwards? Because that would double the polycount! :)

    Last edited: Aug 5, 2008
  4. janis
    janis New Member
    wow i love that clear glass looking material
  5. Wildsketch
    Wildsketch New Member
    No doubt all ZBrush enthusiasts would like to print out their models at full resolution, but you do realize that these are being sent over the internet? How long do you think people will want to wait for their models to upload?

    Also, given what it costs to print out something of size I bet we will all find that we won't be able to afford to print out models of sufficient size to show all the detail that could be put in. In a model of about 4 inches height the finer wrinkles will easily be lost in the grain of the printed material.

    Making a model hollow would indeed double the polycount, as you suggest, so don't create your shell from the full resolution model. Retopologize it at a very sparse base level, then export to your polygon editor, and create the shell. I found the need to relax the inner surface of the shell. Then export the shell back to ZBrush, selectively subdivide the outside surface and project your details onto that. This is what I have done with one of the models I have uploaded.
  6. Owensar
    Owensar New Member
    Yes I agree that there is a need for a larger poly cap perhaps but its also worth remembering, the cost of such detail is expensive and then it must be able to fit inside the 3d printer itself.

    A studio working on a blockbuster motion picture have a larger, more expendable budget.

    That said, quality is important but would you be willing to pay the $xxxx+ price tag of such a piece?
  7. JBoskma
    JBoskma New Member
    Wildsketch: Thanks for sharing your experience on hollowing out models! I am wondering how you would go about connecting the outer with the inner shell, when they are at different levels of subdivissions though. If Shapeways would allow us to actually upload ZTL files, it wouldn't be a problem at all. The size of the zbrushfile for this guy is only 5,54 mb. In obj format it's a 110 mb, which still isn't too big of a deal for me. 20-30 mins upload tops?

    Owenstar: You'd actually be surprised to see where the budgets of films go to. Even on the biggest of productions, things in the effects and post departments have to be done in a very savvy, lowcost way, from time to time. But you're right about the pricing. The reason for me to post here is that I am looking around to find an affordable way to output these type of models. Since they wouldn't serve much more then decorative value for myself. Just gathering food for thought :)
    Last edited: Aug 5, 2008
  8. Wildsketch
    Wildsketch New Member
    You might be in better luck if someone, maybe shapeways later, offfers low-cost large wax prints. Though I wonder if there might be some possibility of melting during shipping.

    I'm surprised at the file sizes you listed. Those really aren't much. I've noticed looking at the files I've been creating for upload that the ZTL files are the smallest of any of them, and the OBJs are only slightly larger. Binary STL files aren't too bad, but collada files are huge in comparison.

    How to get the inner and outer faces at different levels of subdivision? Read carefully over what I wrote. Do not just press divide. Here is my process:

    Make the inner and outer faces different polygroups. This was easy for me the first time because the only opening in my bust was in the base, so i just selected the bottom faces and used group visible, then I could separate it into 3 groups easily. With polygroups defined you can mask the groups you don't want to divide easily. Do this after you re-import after creating an inner shell. Then when you have just one subdivision level you selectively divide only the unmasked faces. Thus you will NOT gain multiple subdivision levels, but instead have a mesh that is much denser on the outside than on the inside. When you have sufficient detail on the outer face hide the polygroups from the inner and border faces. Append your original model and project detail. Export and convert. No sweat.