Making Of 'Traditional Portrait Bust'

Character artist John Crossland shares his techniques and tips for creating a classically-inspired portrait bust in ZBrush and Maya.

At the moment I'm concentrating on further improving my speed, spatial awareness and workflow. The concept for this piece was to do a study of a male adult, sculpted and rendered in a classical style. Using DynaMesh is a good basis to work with digital clay, starting from a small form and developing the piece all the way through to completion. During this making of I will take you through some of the features of DynaMesh and how it helped me to get to a final rendered piece.

Visual library

I usually start my projects with a quick image search to get a feeling for what I want to do, although I have a very large and extremely useful collection of saved images that I have come across previously. I find this really handy to browse through when I'm in need of some inspiration. I never really have any clear plan with these types of studies; I find it far more interesting to go with something that fires my imagination and see where it takes me!

Visual references

Visual references

Base scale object

Once I was happy with the idea, I created an asset which helped me get the correct scale, as well as letting me know which way the sculpture will be facing. Later on I would render the scene using a 'real world' physical lighting setup, so I needed this asset to be on a 'real world' scale.

I started working with a cylinder primitive, and then subsequently created a measurement tape to a scale of 1 foot, measuring the cylinder against it. This meant that when I imported the cylinder into ZBrush I knew I was the right way up and was working to the correct size needed. Sometimes with ZBrush it can be difficult for me to recognize what scale I am working to, so it is a really useful asset to have for future reference.

The scale object in Maya and ZBrush

The scale object in Maya and ZBrush

Initial form building

From the base cylinder created in Step 2, I then selected DynaMesh mode from under the Geometry tab in the SubTool palette. I tend to start with a fairly low mesh of about 16 to 32 resolution and start roughing in the basic forms of the sculpture. As I started to stretch this mesh I re-DynaMesh using the masking function; this helped to keep a clean mesh as I continued to develop the forms of the sculpture. Then, when I began refining further, I increased the DynaMesh resolution to 128 x 256 to give me more control when sculpting the finer details. I usually stop and jump out of DynaMesh at this point.

Initial cylinder scale object to the final rough DynaMesh object (left to right)

Initial cylinder scale object to the final rough DynaMesh object (left to right)

Refining the sculpt

As I continue to develop a sculpt I generally only use a few brushes. The Clay and Move brushes are my favorite for building forms and details. I will use the Slash brush for marking in certain areas, but then always take care to smooth out the surface afterwards.

Once the secondary forms have been developed even further I will then sub-divide the mesh. I find that DynaMesh provides a pretty stable quaded mesh that divides well, giving me enough resolution for the tertiary forms. At this point I also started adding in some simple asymmetry as well.

Initial DynaMesh base to final refined sculpt (left to right)

Initial DynaMesh base to final refined sculpt (left to right)

Using ZRemesher

At this stage, once I'm happy that all the forms are roughly in place, I start thinking about producing a semi-to-final remesh. This will help later for performance, posing and final detailing, not to mention reducing file size.

I duplicated the mesh so that the original remained safe, working on the copy. I defined a few ZRemesher curves on this copy, meaning that ZRemesher understands where we want the topology to flow. With the default settings on, I run ZRemesher, checking over the topology. If I need the mesh to be a lower resolution I will re-run ZRemesher with Adapt and Half on; this retains the newly-defined topology without having to draw new guides. Then I append this mesh back together with the original sculpt.

I subdivided the new appended mesh a few times to give it a higher resolution for the re-projection; if we didn't do this we would subsequently lose our sculpted details. Next I ran the Project All function (which can be found under the extended SubTool palette). Usually the details transfer perfectly but sometimes there might need to be a little mesh clean up or I might need to change the projection distance.

DynaMesh topology to new ZRemesher topology (left to right)

DynaMesh topology to new ZRemesher topology (left to right)

Final details then decimation master

Now that the topology of the sculpt was clean, I continued developing the finer, more subtle details, adding in further asymmetry and expression. The steps previously taken with ZRemesher made posing the sculpture relatively easy, and with solid topology I could step down the subdivision levels and mask off parts like the head and neck. This helped pose the model at a lower poly state instead of trying to manage a denser mesh, and this way the performance was generally more stable.

When I was finally happy with the model, I decimated the mesh. To do this, first I ran Pre-Process; this analyzes the mesh and lets me determine the optimum polygon limit for decimation, usually around 40k. Typically this involves setting the decimate slider to approximately 10 or 20%, and then hitting Decimate. Decimating retains all the details of the sculpture but cleverly outputs a relatively low poly asset for faster rendering; this helped me avoid having to generate UVs or bake textures to get the high resolution detailing.

Decimating the mesh to create a relatively low poly asset

Decimating the mesh to create a relatively low poly asset

Rendering in Maya with mental ray

I imported the decimated mesh as an OBJ from ZBrush into Maya for rendering. Generally I like to set up a simple lighting studio consisting of a floor backdrop, shadow light, rim light and some additional bounce cards for reflections. I rendered with Final Gather enabled to get some realistic soft light to bounce off the sculpture. I'll also added exposure control to the camera and some bokeh depth of field.

I also like to use the shader Mia_Material_X for rendering as it employs physically correct materials settings that can really accentuate clay-like materials.

Maya viewport of render scene

Maya viewport of render scene

Final clean-up in Photoshop

With the final render opened up in Photoshop, I did some minor color corrections here with a Levels layer, and also added in a little atmosphere using the Lighting Filter. Sometimes I'll use Photo filter to add in some soft warm colors and have recently been doing a bit of experimentation with Color Lookup files (this function is one of the new additions to Photoshop) – this can add some interesting visual effects to really show off the final image.

Final image result

Final image result

Related links
Visit John Crossland's website for more of his work
Get the latest ZBrush version
Get the latest version of Maya from Autodesk

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