Tips On Pencil Portrait Sketching - Blocking-in Large Masses Of Value
In this commentary we will discuss the blocking-in of big masses of tone or value.
Tone is generally thought of as shadow. Beginners generally first sketch an outline of the shadow and then fill in the shadows bit-by-bit. They usually start with an eye and then grow out the shadows. Inevitably, the result is a chaos of disconnected darks and lights.
There are two distinct ways of viewing tone: in Western culture we see tone as shadow; in Eastern culture tone is seen as color.
A European viewer seeing a Chinese drawing will be struck by its 2-dimensionality. Conversely, Chinese connoisseurs in the 17-hundreds seeing for the first time European portraits were perplexed by the "dark scuff-marks" under the nose.
Applying, or more accurately, constructing tone should be done with a sculptural sensibility. That is, think of your sketch as a piece of clay that is to be carved. Once roughly carved, you then model the surface forms with varying intensities of tone while manipulating their borders thus defining the forms present in the skull.
A portrait sketching from life or (photograph) starts with the drawing of the construct. Two things must be accurately drawn: 1. the form of the entire head; and 2. the proportions (i.e., length and angle relationships). This is a learned ability that no one is born with.
Once the construct has been struck, the entire head is then broken down into two pieces: a big light and a big dark. No more than that. At this stage, do not concern yourself with whether or not one area is darker than the other. Only the large light/dark pattern counts.
Observe that squinting is a good way to more clearly see the value patterns because you are not distracted by details.
A good rule of thumb is to divide an area in two. For instance, if an observed dark patch is not totally even in value divide it in two and block-in the two slightly differing values. Before long a multifaceted but unified matrix of values will appear.
From the blocking-in of the primary darks you can then readily sketch the features. Over time you should try to remember the entire anatomy and "sense" the form three-dimensionally. This, too, is a learned ability.
You must know your anatomy to be successful in sketching portraits even at the most fundamental level. Learn the anatomy in bite-size portions as you sketch along.
A good way to sketch is to toggle back and forth between line sketching and tonal sketching or hatching. Another way is to first do a entire line sketching of the subject. That is, to sketch a "map" of the head that includes all planes and marks the boundaries of the various tonal areas. As a second phase you can then hatch-in the right values.
While you shade be constantly aware of the planes of the head and the bearing of the light source.
Another skill to be acquired is the skill to cross-hatch areas in a flat and even manner. There is nothing more off-putting than scratchy looking cross-hatching.
Lastly, take note of a strange optical phenomenon called "simultaneous disparity". It happens when light and dark values lie next to each other. In general, white is expansive while black is contractive. The result is that the white patch looks larger than it is while the black patch will look smaller.
In closing, keep the blocking-in procedure simple. Look for big masses first and then for the smaller ones. It is always better to work from the general to the specific. And, at this point, ignore the details.
