Creating believable human face has been one of ultimate goals of many 3D artists. The process of creating an average human face is nothing new or rather a very old topic, however to archive the most realistic and natural-looking possible we have to make the best out of every step we do: from collecting references, planning before modeling,topology, texturing, rendering…etc.
In this study I will only cover part of my research of the modeling process, I will skip through the fundamental things like how to use tools in specific software like Maya/Max or step by step instructions but rather paying more attention to upper level things such as : overall work flow, different approach of modeling, topology, common mistakes …etc as well as all other things that you should put your mind on while working to create a realistic head model.
One fundamental thing you should always aware of is that: always doing research/ planning before digging into doing any actual work. This is critical important for almost anything not just realistic head modeling.
Some master (yes, if there is any) don’t require any reference to work their way up to the final product, but practical-wise and production-wise it is highly recommended or even a must that we must base our work on references, whether it is concept art or photograph…etc. The way we set up references and concept arts have direct influences on our models later. The most important thing in this part is the accuracy and quality of reference photographs, concept arts. If we under estimate or make mistake in this process, we might face serious problems later when the model fit with the front view reference image but does not fit at all with the side view. Other case is that our model look exactly fit in orthographic view but in perspective view it doesn’t look alike the person in reference.
This will consume a lot of time tweaking back and forth, we feel lost and our reference images didn’t come in handy as we expected.
If we are going to take photograph of a real person for references, It is important to take photograph at right angle or else our model will look wrong and we will have to spend considerable amount of time to adjust it. we should also take into account of our camera ‘s focal length. the longer our focal length is, the better reference photographs we have.
Because the longer our focal length is, the closer our view angle to orthographic view ( like front view, side view which we base our modeling on). However, in theory we never get a orthographic reference photograph due to distortion of view angle so the models in 3D always look a little bit fatter than the real person, but this can be solved by additional editing in perspective view. One other thing I like to mention is that we should use even lighting because all the detail will be washed out or become hidden under lighting that is too strong or too low.
Getting reference images into 3D app:
We should not import the raw photo image straight from camera into our 3D software yet, because of the deviation during photograph process we have to check whether these image are exactly fit with each other or not. We should correct our reference images in Photoshop ( using lense profile correction to get rid of the lense distortion) or any other images processing application.
Draw horizontal lines across key elements such as: eyes, nose, mouth and eye browns to check if our references image is consistence and correct-scaled.
3-Edge planning & Topology:
We should always plan our topology before modeling or else we will get lost in maze of edge loops or lost control of our polycount and end up wasting poly on unnecessary parts.We have to sketch out the main shape of the head then base from that we plan our edge structures. Topology is one of key element in 3D modeling in general and especially human face modeling in particular.
Because topology and edge loops play an important part in building up the head volume, face’s characteristics as well as make up what our head model can do/deform in animation.Unlike other parts of character, the head have much more screen time with many close up shots that involve complex facial expression animation like: smile, sad, anger…etc all bring up different shapes and deformations stages of the face.
With a good and smart topology, it is possible for our head model to be able to deform well into to any realistic expression. If we have a messed up topology, our head model can not do a single facial animation and even if it can, the expression will look very un-natural and distorted badly or require a lot of heavy skinning/ deform rigging work. Another plus flint is that nice topology will also make it possible to build the model with less geometry but still look realistic and accurate yet easy to edit and maintain.
3.1- Human Face topology
What is a good head topology? How should we know it is good or bad ? Base on what margin?
In order to answer this question we should go back to our anatomy book and references to look at human face anatomy. Shape of human head, winkles and expressions are all formed and built up by muscles and shape of skull,amount of fat under the skin.The muscles that we need to keep in mind that play important role in forming one person ‘s f