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Zbrush - Why does this happen?

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Just restarted my creation (following the zclassroom lessons) as I was not happy with what happened with the mouth, now I am at the mouth again and it isn't working again, it just becomes these sharp shapes, same with the eyes, doing the smaller parts make the polygons go mental but when I see what is happening in the zclassroom video, the guy is having no problem and all, what am I doing wrong here or missing?



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  • [Deleted User]
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    [Deleted User] insane polycounter
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  • TropicalTommy
  • Neox
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    Neox veteran polycounter
    he just has more geometry to work with, just subdivide your's and it should behave more in line with the tutorial
  • TropicalTommy
    Neox said:
    he just has more geometry to work with, just subdivide your's and it should behave more in line with the tutorial
    Sorry, I am very new at this, what do you mean subdivide ? and how would you do that?
  • TropicalTommy
    CrowXD said:
    See if it is creased if not that, then see if there are any hidden pieces or masked areas and also if you're using Zremesher try messing with the curve and adaptive size.
    I thought maybe there was something wrong within the area I was working so I just tried to make long shapes like wires or something but it happens then, I don't know enough of the program to have a full understanding I suppose but yeah.
  • kanga
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    kanga quad damage
    When you sculpt you stretch out the polygons. Press Shift+ F to look at the wireframe of your model. I haven't seen the whole video but the instructor is using a Dynamesh ball. In the tool menu, go to Geometry and find the Dynamesh group. Open Dynamesh and press the Dybamesh button so that it turns yellow. You can remesh your sculpt at any time by holding Cntrl and draging a rectangular mask in the viewport (away from the model). Once the geometry has been recalculated you keep going. There is also a resolution slider under the Dynamesh button. When your mesh reaches a point where it wont display enough detail, move the slider to the right and remesh your model. Then keep sculpting!
  • [Deleted User]
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    [Deleted User] insane polycounter
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  • kanga
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    kanga quad damage
    you should update your zbrush to 4r8 or else no one can really assure consistent directions.
    Absolutely!
  • cryrid
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    cryrid interpolator
    Neox nailed it; you simply don't have the same amount of geometry that the video does (43k verts on your head vs 285k verts in the video). 

    Zbrush doesn't do any smoothing between its vertex normals. Other 3d programs tend to average these out based on a tolerance angle or manually defined user normals (hard edges, smoothing groups, disconnected polygons, etc) in order to create a smoother appearance, but zbrush keeps the mesh flat shaded (example of what I mean), making the model appear more faceted and planar since you can distinguish every polygon. As a result, a model only looks smooth inside of zbrush when it has so many polygons that they become so tiny that you can't even notice this effect anymore. 

    There are two primary ways of increasing your polygon count while sculpting inside zbrush, depending on your workflow. Both are found under Tool: Geometry.

    • The traditional method is subdivision. This is basically where every polygon gets split into four polygons each time you subdivide (Tool: Geomtry: Divide, or Ctrl+D). A benefit to this method is that you can step up and down through created subdivision levels at will, while preserving sculpted detail (so you can hop down to the lowest subdivision level, make a broader change to the shape of the mouth by moving fewer verts around, then jump back to the highest level and still have finer details sculpted in).

      If you're using this method, you can just sculpt out the face until it gets faceted, subdivide once, and continue sculpting. Rinse and repeat. 

    • A newer method which is used in the video is Dynamesh. This method constantly updates the topology of the mesh in order to create an even distribution of polygons across the surface, based on a resolution that you set (higher resolution = more polygons). The benefit to this method is that you can pull out larger forms from a shape, update dynamesh, and then continue sculpting on the new forms since they now have a good distribution of polygons. This will let you sculpt an entire body out of a sphere by pulling out limbs, for example. You have to turn on dynamesh by using Tool: Geoemtry: Dynamesh, and once it is on you can manually update it by holding Ctrl and dragging somewhere onto the document (not on the model). If you have polyframe turned on so that you can see the wireframe then you'll see what I mean about it changing the topology. Because dyanmesh changes the topology, it will wipe out any existing subdivision levels.

      If you're using this method then just ctrl+drag in order to update dynamesh whenever faceting appears. If it doesn't have enough polygons for what you want, increase the resolution and update again. 

    Personally I like using a combination of the two. I like using dynamesh as a basemesh creation tool, but it's not something I'd typically keep on the whole way through a sculpt. As soon as I have the main forms established I'll turn it off, and from there I'll either treat the result as the first stage of a subdivision mesh, or (more often) I'll use Tool: Geometry: Remesh and use the result of that as the base level.   
     
  • TropicalTommy
    kanga said:
    you should update your zbrush to 4r8 or else no one can really assure consistent directions.
    Absolutely!


    I downloaded the trial version about 5 days ago, guessing 4r8 is the licensed version?

    cryrid said:
    Neox nailed it; you simply don't have the same amount of geometry that the video does (43k verts on your head vs 285k verts in the video). 

    Zbrush doesn't do any smoothing between its vertex normals. Other 3d programs tend to average these out based on a tolerance angle or manually defined user normals (hard edges, smoothing groups, disconnected polygons, etc) in order to create a smoother appearance, but zbrush keeps the mesh flat shaded (example of what I mean), making the model appear more faceted and planar since you can distinguish every polygon. As a result, a model only looks smooth inside of zbrush when it has so many polygons that they become so tiny that you can't even notice this effect anymore. 

    There are two primary ways of increasing your polygon count while sculpting inside zbrush, depending on your workflow. Both are found under Tool: Geometry.

    • The traditional method is subdivision. This is basically where every polygon gets split into four polygons each time you subdivide (Tool: Geomtry: Divide, or Ctrl+D). A benefit to this method is that you can step up and down through created subdivision levels at will, while preserving sculpted detail (so you can hop down to the lowest subdivision level, make a broader change to the shape of the mouth by moving fewer verts around, then jump back to the highest level and still have finer details sculpted in).

      If you're using this method, you can just sculpt out the face until it gets faceted, subdivide once, and continue sculpting. Rinse and repeat. 

    • A newer method which is used in the video is Dynamesh. This method constantly updates the topology of the mesh in order to create an even distribution of polygons across the surface, based on a resolution that you set (higher resolution = more polygons). The benefit to this method is that you can pull out larger forms from a shape, update dynamesh, and then continue sculpting on the new forms since they now have a good distribution of polygons. This will let you sculpt an entire body out of a sphere by pulling out limbs, for example. You have to turn on dynamesh by using Tool: Geoemtry: Dynamesh, and once it is on you can manually update it by holding Ctrl and dragging somewhere onto the document (not on the model). If you have polyframe turned on so that you can see the wireframe then you'll see what I mean about it changing the topology. Because dyanmesh changes the topology, it will wipe out any existing subdivision levels.

      If you're using this method then just ctrl+drag in order to update dynamesh whenever faceting appears. If it doesn't have enough polygons for what you want, increase the resolution and update again. 

    Personally I like using a combination of the two. I like using dynamesh as a basemesh creation tool, but it's not something I'd typically keep on the whole way through a sculpt. As soon as I have the main forms established I'll turn it off, and from there I'll either treat the result as the first stage of a subdivision mesh, or (more often) I'll use Tool: Geometry: Remesh and use the result of that as the base level.   
     
    I have watched the first two videos over and over just trying to get the face correct, but somehow missed the ctrl + d/dynamesh, still don't see it but oh my god, thank you, I have been stuck on the finer details for days and days.

    I pick the Dynamesh128 ball at the start, but that is the only dynamesh thing in the video I saw.

    Pretty much fixed everything and added a ton of details in about 20minutes, it is insane how easy it is now that I have so much to work with, only issue is that when I try to smooth something, it doesn't seem to work at all or rather I can't smooth anything that is an indent, wondering if there is a way to go back with ctrl+ D then forward again?

  • TropicalTommy
    kanga said:
    When you sculpt you stretch out the polygons. Press Shift+ F to look at the wireframe of your model. I haven't seen the whole video but the instructor is using a Dynamesh ball. In the tool menu, go to Geometry and find the Dynamesh group. Open Dynamesh and press the Dybamesh button so that it turns yellow. You can remesh your sculpt at any time by holding Cntrl and draging a rectangular mask in the viewport (away from the model). Once the geometry has been recalculated you keep going. There is also a resolution slider under the Dynamesh button. When your mesh reaches a point where it wont display enough detail, move the slider to the right and remesh your model. Then keep sculpting!
    My Dynamesh was already on/highlighted yellow, so I tried to do the ctrl and dragging, but now I am stuck on just left and right clicking and it makes a mini version of my already made model appear?

    I have had this before, but end up closing and restarting as I don't now how to stop this, shfit + f made me zoom into a point I couldn't zoom out of or something also, any ideas what I did wrong?
  • cryrid
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    cryrid interpolator
    Pretty much fixed everything and added a ton of details in about 20minutes, it is insane how easy it is now that I have so much to work with, only issue is that when I try to smooth something, it doesn't seem to work at all or rather I can't smooth anything that is an indent, wondering if there is a way to go back with ctrl+ D then forward again?


    If you have subdivision levels, there should be a slider under Tool: Geoemtry that you can use to step up and down them (D and Shift+D can be used as shortcuts for this). 

    Note: If you hit D without subdivision levels then it will turn on dynamic subdivision, which is basically just a preview and not the same.  

    My Dynamesh was already on/highlighted yellow, so I tried to do the ctrl and dragging, but now I am stuck on just left and right clicking and it makes a mini version of my already made model appear?

    Sounds like you've left edit mode. Clear the document (ctrl+n), draw the 3d model out once, and then click the Edit button (t) to continue sculpting. 

    Learning the difference between the 3d model (tool) and the 2d document and why edit mode is used in the first place should be the first thing any zbrush tutorial starts with, but often everyone (tutors included) just jump right into the sculpting and so new users get pretty confused when it comes to this fundamental aspect of the program's interface. 

  • TropicalTommy
    Thanks for the replies, I will read up on your post and see what I can find on the net for videos, thanks again.
  • kanga
  • TropicalTommy
    cryrid said:
    Neox nailed it; you simply don't have the same amount of geometry that the video does (43k verts on your head vs 285k verts in the video). 

    Zbrush doesn't do any smoothing between its vertex normals. Other 3d programs tend to average these out based on a tolerance angle or manually defined user normals (hard edges, smoothing groups, disconnected polygons, etc) in order to create a smoother appearance, but zbrush keeps the mesh flat shaded (example of what I mean), making the model appear more faceted and planar since you can distinguish every polygon. As a result, a model only looks smooth inside of zbrush when it has so many polygons that they become so tiny that you can't even notice this effect anymore. 

    There are two primary ways of increasing your polygon count while sculpting inside zbrush, depending on your workflow. Both are found under Tool: Geometry.

    • The traditional method is subdivision. This is basically where every polygon gets split into four polygons each time you subdivide (Tool: Geomtry: Divide, or Ctrl+D). A benefit to this method is that you can step up and down through created subdivision levels at will, while preserving sculpted detail (so you can hop down to the lowest subdivision level, make a broader change to the shape of the mouth by moving fewer verts around, then jump back to the highest level and still have finer details sculpted in).

      If you're using this method, you can just sculpt out the face until it gets faceted, subdivide once, and continue sculpting. Rinse and repeat. 

    • A newer method which is used in the video is Dynamesh. This method constantly updates the topology of the mesh in order to create an even distribution of polygons across the surface, based on a resolution that you set (higher resolution = more polygons). The benefit to this method is that you can pull out larger forms from a shape, update dynamesh, and then continue sculpting on the new forms since they now have a good distribution of polygons. This will let you sculpt an entire body out of a sphere by pulling out limbs, for example. You have to turn on dynamesh by using Tool: Geoemtry: Dynamesh, and once it is on you can manually update it by holding Ctrl and dragging somewhere onto the document (not on the model). If you have polyframe turned on so that you can see the wireframe then you'll see what I mean about it changing the topology. Because dyanmesh changes the topology, it will wipe out any existing subdivision levels.

      If you're using this method then just ctrl+drag in order to update dynamesh whenever faceting appears. If it doesn't have enough polygons for what you want, increase the resolution and update again. 

    Personally I like using a combination of the two. I like using dynamesh as a basemesh creation tool, but it's not something I'd typically keep on the whole way through a sculpt. As soon as I have the main forms established I'll turn it off, and from there I'll either treat the result as the first stage of a subdivision mesh, or (more often) I'll use Tool: Geometry: Remesh and use the result of that as the base level.   
     
    I have watched the first two videos over and over just trying to get the face correct, but somehow missed the ctrl + d/dynamesh, still don't see it but oh my god, thank you, I have been stuck on the finer details for days and days.

    I pick the Dynamesh128 ball at the start, but that is the only dynamesh thing in the video I saw.

    Pretty much fixed everything and added a ton of details in about 20minutes, it is insane how easy it is now that I have so much to work with, only issue is that when I try to smooth something, it doesn't seem to work at all or rather I can't smooth anything that is any more than a slight indent, any ideas? wondering if you can go back with Ctrl+D in some way and then forwards again?
  • TropicalTommy
    kanga said:
    Somehow missed this, thank you.
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