Drawing a face realistically is probably one of the biggest
challanges when it comes to art.
There's no exact formula, but here are some characteristics that work for me and I can pass on:
The face can be divided into three parts:
1/3 goes from hairline to the center of the eyebrows
2 /3 starts between the eyebrows and ends at the tip of the nose
3/3 reaches from the tip of the nose to the chin.
These are approximate measures. Of course you have to mind the perspective.
More characteristics are:
- The eyes are always in one line or bow, since head and face are round.
- The distance between the eyes is approximately the width of an eye.
- The mouth is parallel to the eyes plus eyes and mouth are "congruent" to the centerline, or the vertical axis.
No matter what perspective or angle these characteristics stay the same.
It seems logically or too simple to mention, but a lot of mistakes happen, because these characteristics are not in alignment.
As a result the face looks asymmetric.
To give you a better idea here are four sketches from different perspectives:
I drew an extra strong center line. From there it is easy to measure the rest. I also added the two bowed lines through eyes and mouth. As you can see they run parallel to each other.
Despite the different angles and perspectives those lines
and characteristics stay the same and are in alignment. It doesn't matte
if the person looks down or upwards.
I have not added the trisection (the three parts I mentioned at first) but this can easily be measured.
To me it is easiest to start with the eyes and nose, therefore the center of the face. This is up to you however.
I recommend to learn drawing the proportions first and once you are practiced you can move on and start with shading. But before you do that the proportions have to be correct.
Given time you get a better feeling for proportions and
you learn to see things that the untrained eye cannot see.
When it comes to drawing a portrait of a specific person and not just any face, it takes more than technical advice.
Every face is different. Every person has other characteristics and features. So the measurements vary from face to face.
It's always good to keep that in mind. It is not just about an object, but a real person.
In the end the only trick is to practice.