Realistic Facial Features in 3D Character Sculpts

Arthur Hernandes shared his realistic character workflow and talked about the production of Cabal Patriarch with ZBrush, Maya, and V-Ray based on the actor James Cromwell.

Introduction

Hello, my name is Arthur Hernandes and I am a 3D character artist, 31 years old, from São Paulo, the largest Brazilian city. I have been working in CG for almost 16 years. Most recently, I participated in a CG Brazilian feature film and its platform game, and during this year I had the opportunity to work as a 3D character artist on the game Skydome.

I have always liked video games and their art, so this was a natural path for me. Initially, I started my career as a 3D animator who liked to model the characters as a hobby. Eventually, I noticed that my passion for 3D modeling was bigger and decided to change my focus.

Idea & References

At first, I planned to conduct a study. I have always liked the realism that the big companies like Blizzard and Blur were capable to exhibit in their cinematics, so I wanted to try something similar. The original challenge was to create a complete 3D character posed in a certain way that would be able to transmit its own history. The Cabal Patriarch has always been one of my favorite “Magic: The Gathering”  cards, so I thought that character would fit my task perfectly.

The first step was to search for some face references. Since I wanted to be as realistic as possible, I looked for some actors that would suit a good Patriarch. In this sense, I think that James Cromwell would be the best choice. I googled his roles, mostly the shots of his character in the second season of American Horror Story, and separated the references. A good thing with references from movies is that you are able to see what you need from different angles and under different illumination, so you can notice details that are hidden in just a single ‘shot’.

Another important aspect to keep in mind during this process is the kind of standard you want to achieve. In this sense, it is good to have other good artists as a reference. For me, these were Rafael Grassetti, Steve Lord, Adam Skutt, Vimal Kerketta, Kris Costa and many others.

Concerning the challenges, I would say that one of my first problems was the lack of proper focus. The initial goal was too generic, so I was not able to give the needed attention and care to every element of the character. Then I decided to focus only on the face first and move to the next parts after making it as good as I possible. Besides that, creating a realistic 3D face could be challenging on its own: the hardest part, as always, was to make it as similar to the reference as possible. It is important to emphasize that this is an iterative process which took several versions until the final one was made.

Sculpting

The sculpting process was pretty straightforward. I started with a dynamesh with just a few subdivisions and then blocked a very simple skull. Subsequently, I added generic primary forms of the nose, ocular cavity. etc. just to establish the model’s foundation. After these landmarks, I could take care of the elements’ dispositions in relation to the actor’s face. Slowly, I refined the physical characteristics like the nose size, eyes distance, and mouth shape until I reached the desired form. With a rough model in hands, I focused on the secondary forms like expression lines, wrinkles, plane differences, etc. It is important to note that in this step I usually work without symmetry in order to give more realism to the model.

Details

After I finished the primary and secondary shapes I started to take care of the little details. I approached the areas containing excess skin with the standard brush and Clay. For the cavities, I used Dam standard to accentuate the details and make them more perceptible. Besides, I used Pinch and Inflate to keep the skin folds close.

For more specific elements like the skin pores, I made used alpha together with Drag rectangle to have an initial base and later I manually added some more details.

In the final file, the model had approximately 6 million polygons.

Eyes

When working on the eyes, I usually start with just two spheres: one for the cornea and the other one to the sclera, iris, and pupil. However, in this project, I used a different approach and created three distinct meshes: one for the sclera and cornea and two for the iris and pupil separately.

As soon as I had the eye’s base model, I imported it to ZBrush and painted with Zspotlight using real-eye pictures as a reference. The basic idea was to paint the color map first and then create the sculpt details from it. After, that I transformed it into a mask and used Standard and Inflate brushes to add the texture details. Then I used brush clay to leave the surface more irregular. Finally, I applied the same workflow to the iris: painted a color map, transformed it into a mask, and sculpted new details.

For the eye shaders, I used the V-Ray Mtl with some texture maps to control the relevant parameters, like reflection, opacity, Albedo and normal map. The shader was quite simple and the realism obtained was basically a combination of a regular sculpting process combined with good lighting to get an interesting reflection effect in the eyes.

Skin

Since the original idea was to obtain the most realistic model possible I used V-Ray’s FastSkin Shader. It simulates the behavior of the real skin in a virtual scenario. After applying the shader I modified its parameters in a proper way: I intensified the translucency effect which increases the scatter rays value, adjusted the sub-surface colors to have a proper skin tone and the scatter to obtain the characteristic redness effect of the light penetrating the skin. However, before starting to paint the maps I searched for skin references on the internet in order to ease the face coloring process.

For the Albedo map, I used ZBrush and started with the same color that I used in the Sub-scatter parameter. After that, I slowly added red into the warmer areas of the face, and then some blue and green. Finally, I input some specific spots that appear on the old skin.

With Albedo map in hands, I was able to create the Specular and Glossiness maps. I initialized both of them in black and then added white spots in the areas that I wanted to be brighter like the nose, mouth, forehead and eye bags. Subsequently, I mixed a cavity map made with ZBrush and a b/w version of the Albedo in order to give a greater variation range of brightness on the face surface.

Finally, in order to bring the sculpted details into ZBrush, I exported the Displacement and Bump, combined the 2 maps and applied the result as a displacement map in the shader.

Hair

The hair creation process was quite simple. I created masks showing the needed areas with ZBrush, applied Fibermesh and brushed the hair with Move Brush. The hairs themselves were created with the help of Maya’s nHair system. Every type of hair (facial, eyebrow, etc.) has its own nHair, thus we are able to assign specific features to each part just by changing the desired parameters.

In order to create the nHair, you need to make a 3D object that will serve as a generating surface. After that, you can apply the nHair and add the created Fibermesh curves. Every type of hair has its own specific nHair configuration. In general, I always adjust the Thinning parameter in order to generate a more natural and randomized strand’s size, increase the Clump Width to better distribute the hair roots, and the Clump Width Scale to have more separated hair tips.

Besides, the V-Ray Hair was used for all the character’s hair, but its parameter values were tuned for each area separately. The opacity, for instance, was decreased by 40% for the thinner hair (nose, ears) leaving it less apparent. Finally, to have a more robust beard, I changed the Primary Amount in order to remove its brightness, and Primary Glossiness to emphasize the bright areas.

Lighting & Rendering

I chose V-Ray as a render engine because I really like the results I get with the Skin shader, plus its relative simplicity.

The idea was to show the model in a neutral light without color interferences. I made a standard rig with a top-down key light in order to give volume to the model and highlight the shades, especially in the eye area, two backlights to give the translucency effect that the sss provides, and finally, a bottom light to adjust the shades in neck and nose areas. Besides, I inserted two dome lights with HDRI maps to complement the lighting set: one to illuminate the darker areas and another one to intensify the material specularity.

Concerning the shaders, I applied Fast Skin to the face, V-Ray Mtl to the eyes and V-Ray Hair to the fur.

Arthur Hernandes, 3D Character Artist

Interview conducted by Kirill Tokarev