3D Artist
Feb
22

Model a historical portrait in ZBrush

Tips & Tutorials
by
Ang Lu

Discover techniques for creating a realistic image of a Chinese empress with intricate clothing from the Qing Dynasty


Model a historical portrait in ZBrush

This tutorial was written by the amazing Ang Lu and appeared in issue 112 of 3D Artist. Subscribe today and never miss an issue!

Tools used

Maya, ZBrush, Mari, Nuke, Photoshop

In this tutorial, you will learn how to create a realistic portrait image using software such as Maya, ZBrush, Mari and Nuke. We will take you through the process of modelling, texturing, shading, hair creation, rendering and compositing. Instead of using external plugins for hair and rendering, we will be using XGen and Arnold 2.0 for Maya 2017. This tutorial is suitable for beginners because it will help you to understand the ideas behind the production, but you should also have some knowledge of the software involved to achieve the desired results.

 

Step 01 – Create the base model


Model a historical portrait in ZBrush

The first step is to create a base model based on the references we’ve found. You don’t need to think about the details at this stage. Our main purpose is to ensure we have the correct proportions of the model and to think about the method of production for each model. We need to know which parts will be done in Maya and which parts will be easier to build in ZBrush directly. Starting off with a clear idea of what you need to do is very important for improving your production efficiency.
 

Step 02 – Work on the high-poly head


Model a historical portrait in ZBrush

Import the head we created in Maya to ZBrush. Then we can import reference images by using Texture>Image Plane>Load Image. Reference Views enables you to import your images from different angles, which is very useful for creating a precise model. For the skin details, we can use several different skin brushes. First we brush big details such as pores and wrinkles and then cover them with a layer of fine particles.
 

Step 03 – Make the headdress


Model a historical portrait in ZBrush

The jewellery structure on the headdress is really complicated, so we’ll choose to create the model in ZBrush directly, which is easier than creating a low-poly model in Maya. DynaMesh can be used to reconstruct the model’s wireframes, so we can sculpture the shapes we want. Then we can use ZRemesher to make our wireframes rational, but this may require a high poly count to keep the details. Therefore we’ll use Decimation Master to maintain the details with the lowest poly count, while keeping the UV. It is a very useful tool.
 

Step 04 – Sculpt high-poly cloth


Model a historical portrait in ZBrush

Now we will import the basic model to ZBrush for sculpting. Although I considered using Marvelous Designer for the cloth at the beginning, I think this dress is relatively simple and can be quickly sculpted by using ZBrush. After completing the high-poly model we use GoZ to go back to Maya for unfolding the UV. Here we need to remind you to ensure that Maya has mental ray installed when you use GoZ.
 

Step 05 – Model the high-poly chair


Model a historical portrait in ZBrush

We built the chair frame in Maya then completed the complex parts in ZBrush. Similarly, we used DynaMesh to create the complex structure of the model. The model structure of the chair is very complicated, but we won’t spend too much time on it because it is only part of the background.
 

Step 06 – Texture the head


Model a historical portrait in ZBrush

To make a texture map for the face, stamp a real skin image in Mari for the model and remove the pores. We will then add the details for the skin texture from ZBrush when we come to sculpting. Next we create the displacement map in ZBrush and convert it into a High Pass map in Photoshop. Then we overlay to our skin colour to generate diffuse. These steps need to be done to ensure that we get the correct texture details after render. We have to create two specular maps, one used for large area highlight and another one used for partial highlight.
 

Step 07 – Texture the cloth


Model a historical portrait in ZBrush

We import the model into Mari, and then we stamp a layer of fabric texture and create a new layer for the pattern stamping. Mari enables you to adjust and merge layers separately as in Photoshop. We hide the layer of pattern while creating specular and bump. The hardest part of creating this cloth is to find the patterns on the clothes.
 

Step 08 – Set the lights and render


Model a historical portrait in ZBrush

After we finish the textures, we are ready to render in Maya. Firstly we will create an aiStandardSurface shader and turn off the diffuse and specular, then we just connect the bump and displacement. Secondly, we create an aiAreaLight and aiSkyDomeLight for rendering. By using grad mold rendering, it is easier to see the details of the effects.
 

Step 09 – Headdress shader


Model a historical portrait in ZBrush

The jewellery on the headdress is made of metal, so we need to adjust the strength of Metalness in aiStandardSurface. For example, if we set it to 1, it will be all metal, with only specular and without any diffuse. Here we set it to 0.9 so that it remains slightly diffuse, which will be easier to adjust during the composing stage. We have not painted the map for this part of the model, because we want to create the map with 3D textures in Maya. We can adjust the specular of metal and bumps by combining several different 3D textures.
 

Step 10 – Create the shader for the head


Model a historical portrait in ZBrush

After we confirm the displacement value, we connect to the specular map and reduce the Weight of Base to 0, which will enable us to see the specular effect conveniently. We connect spc01 to Specular and connect spc02 to Coat. When we adjust one of the specular maps, we also reduce Weight to 0. The SSS map is transformed by diffuse, and we create an aiColorCorrect node in Maya to modify the map. When we make SSS, we need to turn on the Weight of Subsurface to adjust the intensity of Radius and Scale.
 

Step 11 – Make shader for the eyeball


Model a historical portrait in ZBrush

The eye consists of two models, one is the eye with a texture map, another one is the eye with glass. After painting the blood vessels of the eyeball, we extract the red alpha to create bump. When we make the glass material for the eye, you need to remember to tick off the Opaque option of the model. Arnold 2.0 uses Transmission instead of the previous Refraction, and the refractive index is controlled by IOR.
 

Step 12 – Shader for cloth


Model a historical portrait in ZBrush

This part is relatively simple. After setting the bump and displacement, we connect the specular map to material for adjusting brightness and roughness. The effects of rendering may not be obvious because some details on the clothes are relatively tiny. So we can slightly increase bump or displacement while adjusting specular to add more details to the image.
 

Step 13 – Create the hair


Model a historical portrait in ZBrush

Switch the workspace to XGen – Interactive Groom, select the face of the model that requires hair and click the icon to create hair and fur using interactive groom splines. We can adjust the Density, Scale and Width Scale in the Attribute Editor. Now, we can start creating the hairstyle. We then use the Comb tool to put all the hair to the back of the head and use the Clump tool to gather the hair together in the back. Finally use the Noise tool to disrupt the hair near the temples.
 

Step 14 – Add eyebrows


Model a historical portrait in ZBrush

We use the same process described in Step 13 to create eyebrows, and we will use the Cut tool to make the eyebrows different lengths. When using the Comb tool, choose Collide With Meshes to prevent the hair from piercing the model. We may comb both sides of the eyebrows at the same time after we set up Symmetry. Then we can create each side of the eyebrow separately, because our real eyebrows are asymmetrical. We can also modify the shape of the eyebrows by adjusting the model structure.
 

Step 15 – Make the lashes


Model a historical portrait in ZBrush

We use another method to create eyelashes. We switch the workspace to Maya Classic, open the XGen window, click Create New Description, choose Placing and Shaping Guides and then we can start to create. Click Add or Move Guides to add guides to our model, and we can adjust Density, Length, Width and Taper in Primitives. We select all of the guides and click Modify As Curves in Utilities so that we can adjust the shape of the eyelashes, and once we have done the adjustment click Accept. Then we click Update The XGen Preview to see the effect. Finally, we add a few tools including Clump, Cut and Noise to adjust the distribution of the eyelashes in Modifiers.
 

Step 16 – Create the fuzz


Model a historical portrait in ZBrush

Just like creating the eyelashes, we first select the face of the model (apart from the hair, eyebrows and mouth areas) and then we click Create New Description. However, this time we select Groomable splines which is used for short hair, fur, grass and so on. Also, we adjust the Density, Length, Width and Taper in Primitives after we create the fur. Then we add Cut and Noise to finalise the effect in Modifiers.
 

Step 17 – Camera and render settings


Model a historical portrait in ZBrush

After setting up the location of the camera, select Enable DOF in Camera Attributes. We use the Distance tool to set two locators to measure the distance between the camera and the eyes, and then we set our screen on virtual focus. With the AOVs, we can add it in Render Settings or we can launch the Render Setup window to set up our own. We can increase the Sample and Ray Depth when we are ready for the final render.
 

Step 18 – Composite in Nuke


Model a historical portrait in ZBrush

Import the EXR file from Maya to Nuke. Combine the diffuse, specular and SSS together by using the Merge node, and then select the mask channel. We can adjust the brightness, colour, saturation and gamma by using the Grade node and Saturation node for different materials. Finally import the image to Photoshop and use Camera Raw for final adjustment.