Making of Mr.Obama Digital Portrait

By 3DM3

Since my project was related to well known public person finding good references was easy task but it was impossible to find images that could be useful for assembling good image plains so i relied mostly on eyeballing techniques.

Hi my name is Toni and i am going to walk you trough process of making digital portrait.
Making a digital portrait can be very difficult task if not prepared well,
so my first advice will be to get a lot of references for your project.
Since my project was related to well known public person finding god references was easy task but it was impossible to find images that could be useful for assembling good image plains so i relied mostly on eyeballing techniques.

Base Mesh

With all my personal project I try to learn as much as I can so I often change pipeline and workflow as well. Don’t be afraid to try some new techniques and apps since technology is growing every day giving us opportunity to work more efficiently. In this project I will be switching between Maya, ZBrush, Silo, Uv layout and Photoshop.

First thing I did was building simple base mesh in Silo using smoothed cube primitive and extruding few faces from bottom to make neck volume and shoulders. You can see Silo base mesh in figure below

Than I import base mesh as .obj file in ZBrush and started the sculpting. In this stage I was focused on overall shape and volume of model and I was not concerned with likeness features. My goal was to make good human bust sculpt and build new topology over that hi-res sculpt. That way I can have more efficient edge flow for further sculpting. ZBrush mesh base sculpt is presented in figure below.

When it comes to remeshing your sculpt there is many good solutions. I could use ZBrush Z-sphere or even Topogun but I’ve decided to do it in Silo which also have some nice tools for that task. After laying down new topology I quickly realigned my base mesh with reference image using move brush in Silo. After half hour of pushing and pulling I had good base mesh with some decent percent of likeness I can further refine in ZBrush.

Have to revisit it later. In sculpting process mesh can be deformed behind point where your polygons align with distortion free UV’s so I will revisit this problem. Before adding more details to mesh I often do UV part. For that task I use great app called UV layout. I don’t spent much time on UV’s at this point because I will do it after completing this model.

For well trained artist task of building base mesh in such way can take between 1-2 hours. This mesh can be used in many other project because it have god mesh structure and volume.

Sculpting

After building base mesh I imported this new base in ZBrush for further refining and sculpting. Be sure to focus on overall shape and volume of model instead of fine detail. Both overall shape and details are equally important but at first stage I suggest you to stay at lower subdivision levels and make good use of every edge and polygon before stepping up to higher level.
Don’t forget to use references images at all time. If you are not happy owner of two monitors it is helpful to print those images on paper. Sculpting in ZBrush is really fun but be careful not to get carried too much and often check proportions of your model.
After completing the sculpture I exported the model in lower subdivison level and once again check my UV’s in UV layout. Then I re-import that mesh again in ZBrush. Now I have completed sculpture with distortion free UV layout and ready for texturing.

Texturing

For texturing part I use texture projecting techniques. Many people think that ZBrush can only paint on poly’s but using projection master you can actually project your painting directly on texture. For my model I have used 4k size textures. Here is quick explanation of workflow in this technique:

Make new document in ZBrush and resize it to your texture size or more.
Load your model and drop it on canvas than press “T” to get in to edit mode.
Once in editing mode you position your model to camera in direction you want your projection to be.
Make new texture any size you want for example 4096 x 4096.
Press “G” to enter projection master and choose color projection with no fade option and press drop down.
Now go to Zapp link which will transfer your canvas to Photoshop. Now u can overlay Photo of your reference over your ZBrush model and realign facial futures of your photo to match your model. I find liquify tool in PS most useful for that task.

For more tips about Zapplink check www.zbrushcentral.com

After saving your Photoshop work go back to ZBrush and your texture will be projected on the ZBrush canvas over your model exactly you made it in PS. Because you are now in projection master, press G again to pick up your projection. After couple of seconds your projection will be baked on to your texture. Repeat this process few more times but with different angles and save those textures as different files. Now you can stitch those projections together in Photoshop.
From basic color texture I made six different textures such as epidermal and subdermal, specular, bump and so on.

Scale of the model is one of the important things that must be well tuned because subsurface scattering weights relies on scale of your model. If you are not sure how to adjust scale of your model in Maya or max here is tip.

First load your model and apply fast skin material on to it.
Place some point light in front of your model and one point light behind model .
Point light behind should shine through your model in red color when rendered.
That red color comes from back scatter component of sss fast skin shader.
Now adjust scale of your model or even better scale conversion parameter in material until that red color only shines through the ears of your model.
That way you will be sure that your scale is correct since fast skin shader comes already tuned for optimal results.

Hair

For the short hair I use Maya fur. I don’t have any particular tips for Maya Fur, only thing is when you test fur be sure to turn off all shadows because it can take long time to render specially with raytracing shadows. Here is hair setup:

Lighting and Rendering

For the final rendering I use high density mesh since I am doing still image and I don’t care if model will be animatable. Rendering is the part which I find most time consuming because it takes a lot of test to come up with good relations between lights and shaders. Every test I did took between 3 – 15 minutes. For the lights I have used 4 lights…

Two back lights are colorized, one slightly blue and other yellow. Main key light comes from the side and above and I have one big aerial light in front of the model for key light. I set two area lights that are not illuminating scene but they are only visible in reflections (for the eye). All of the lights in my setup are area lights because they produce nice soft shadows but in cost of more render time.