classical realism

Light and Shadow on Geometric Forms


Considering Light and Shadow in Basic Geometric Forms
The three most useful geometric forms we are going to consider are the sphere, the cylinder and the cube. 
Let’s look at these and consider the lighting situation that we normally find ourselves in. 
Typically if light is coming from above and off at and angle (in these cases the light is coming from the top left), then the lightest light will be inside the form, nearer the top and nearer the left of the form.  As the various planes of the form turn away from the light, the value of the light gets progressively darker, until we arrive at a part of the form that turns completely away from the direct light source.  From that part on, the rest of the form will be in shadow.
This lighting situation is called crest lighting, and will occur far more frequently in classically lit subjects and scenes.  The second lighting situation we may encounter is called rim lighting, where, as the name suggests, the lightest light falls directly on an outer edge.
In either case, we have one part of the form in the light and one part in shadow. 
When we have blocked-in our figure or portrait or still life, the next step is to map out a light and shadow pattern, and then to get that shadow area to a value #6.  This would give us a drawing that consists of a) light, and b) shadow.  The light are is the white of the paper, and the shadow area is a flat value #6.
Most students can immediately identify variations in the shadows but not so many see those in the lights. 
In fact, we need to invert this thinking and “seeing”.  In classical drawing, the shadows are areas of rest.  Details here are subdued and the range of values is compressed, in favour of bringing out details and full rendering and expanded values in the lights.
As we consider our most basic geometric forms, let us identify the variations in both the lights and in the shadows.  Once identified and named, we can more easily recall the rules of each part, and apply these logically to our drawings.
© Mandy Boursicot 2013

The Lights

Value #1 the white of the paper will be the lightest light, the diffuse highlight and the spectral highlight.
Value # 2 following on from the lightest light, is some slight darkening of the lights, and possibly turning of the form away from us, in the lightest area (see sphere and cylinder).
Value #3 this is the light half-tone or the normal local value of the object
Value #4 this is where the light half-tone gets a bit darker so it’s the medium half-tone
Value #5 this is the dark half-tone or the turning tone of the lights are they are at their darkest, which is just before the form turns into the shadow.
All of the above would be either the white of the paper, or rendered in gradations with a 2H and then HB in the darkest half-tones
When we render the lights, we should work with pencil strokes that follow the basic geometric form and work from the darkest part towards the light with gradations of tone that are getting perceptibly lighter.
Form Shadows
The shadows were originally set at a value #6.
Eventually we will need to make those variations in the shadows, so here is an brief explanation of what we see:
Value #7 is right on the edge where the light and the shadow meet.  This is sometimes referred to as the “bed-bug line”, or the “terminator line”, or simply “the terminator”
Just past our bed-bug line is the core of the shadow and reflected light, which would be our original value #6. 
That is followed by some turning tone in gradations which might lead us to a value #7.5 or 8.
On the ground plane is the cast shadow. 
Cast Shadows
Cast shadows have their own rules.
Firstly, they are darkest nearest the form casting the shadow (value #9) and then get lighter the further away they are from the form casting the shadow.
They have an edge or an outline, which is sharper and darker nearer that original form, and this outline gets lighter and more diffuse the further we go from that form.
In addition to this, just outside of the cast shadow is a penumbra.  This is an extra secondary and lighter shadow that becomes more visible and more diffuse the further we get from our original form
Occlusion Shadow
The last kind of shadow is the “line” right under the form.  This anchors the form to the ground plane.  It is called the occlusion shadow or proximity shadow.  This occlusion shadow is the darkest shadow and occurs at the point of contact of the form with the ground plane.  It often leads into the cast shadow.
© Mandy Boursicot 2013

As can be seen, in these drawings, the space occupied by value #1 and #2 are fairly even, and then 3, 4 and 5 occur in rapid succession.  This is because the light diminishes at an exponential rate as the form turns away from the light source, and heads towards the shadows. The dark rim directly under the cylinder is the occlusion shadow.  On the perimeter of the cast shadow is the penumbra.

 © Mandy Boursicot 2013

In this cube, the lights are very light, only using values 1 through 3, and then the form of the cubes turns a sharp corner into the shadows.  The shadow directly under the cube is the occlusion shadow. 

Teaching Schedule for April 2013

Here’s the April Schedule.

If you’re in the P2 group, please note the switch from Tuesday to Thursday during April.  In May there will be a switch back to Tuesdays, but more about that later !

Shadow Shapes


This iconic posterized image should be familiar to most people, and is instantly recognizable as Che Guevarra, despite being a simple pattern of light and shadow.  The original picture of Che has been altered from including all the finer shapes and subtle inuendos of half-tones and details in the darks.  In other words, the infinite variety of values has been reduced to simply two values.  Such an abbreviated value image, whilst recognizable in its major statement, is also devoid of much of the beauty and delicacy that comes with a well-articulated and intelligently-refined image.
The two-value image is graphic and basic. Yet it serves an essential function.  The precise articulation of the shadows pattern on the inside of the form describe changes in the topography, and thus forms the framework on which the rest of image will be built and elaborated.

Aside from the posterized versions of photos which I have just shown, we use shadow shapes to start our drawings and paintings. 
Here are some examples of portraits and figures in their shadow shape stage:

 – Academy of Realist Art, Toronto
 – Zdenek Sychrava

© Mandy Boursicot 2013

Classical Order of Light


In addition to light and shadow to describe a three-dimensional object, we use a range of values from light to dark to describe the volume of the object as it turns towards or away from the light.  If there is more than one object, or if it is a complicated subject, such as the human form, then it’s more than likely one section will be closer to the light source than another part (a model’s chest, for instance) would be closer than his foot) and hence the light hitting the closer section would be brighter than the light hitting the further section.  We would then replicate the quality of this diminishing light in our portrayal of that model.

To this end, we use a nine-step value scale to describe different tones in the light and dark, and create the illusion of form and volume, and recession into space.
– Academy of Realist Art
In this system, the number 1 value represents the lightest of the lights, which will be the white of the paper, and the other extreme, the number 9 value, represents the darkest of the darks, which is the blackest that we can achieve with the medium we are using (this can vary depending on whether we are using oil paint, printer ink, charcoal, pencil, etc.)
In the sphere with light hitting at 45 degrees, we can render the whole volume of the sphere with different tones as follows:
– Classical Drawing Atelier, Juliette Aristides

Even though the eye can distinguish many more values than can be represented in pencil, it is enough for the artist to use nine values, as the viewer will read our smaller range of values in the same way as they would read a much greater range of values in nature.
In our nine value scale, the lightest values, 1 and 2, will represent the lightest lights.  3 and 4 will represent the middle lights.  5 and 6 will represent the darkest of the family of the lights, those halftones.  7, 8 and 9 will represent the shadows, that is, the light shadows, the middle shadows and the dark shadows respectively.
A later blog will deal with the nature of different shadows.  For now, it’s worth noting that reflected lights belong to the family of the shadows and will most likely be the lightest of the darks.

© Mandy Boursicot 2013

Light and Shadow

The knowledge that we seek to increase, to inform our understanding of visible reality, is based on the physics of light, the examination of human anatomy, the study of perspective, the conceptualization of bodies in space and in motion, and the mathematics of geometry.  These are widespread fields of study, and the artist may only need to consider very narrow and specific portions within each discipline.  This blog will aim to cover those aspects that relate specifically to purposeful application by the artist, and these will be covered in due course.  For now, we will start with the foundational groundwork .
First, in order to have a common understanding, it is necessary to have a common vocabulary, to discuss both the most basic principles and finer points.
Light and Shadow
Classical Realists are concerned with the creation of an illusion of reality, specifically the illusion of a three-dimensional world on a two-dimensional surface. In order to achieve a masterful drawing, the realist needs to understand and apply the principles of the Classical Order of Light.
Without light, nothing is visible.  What we aim to create on paper is our closest approximation to what the eye sees.  We therefore need to understand how light works, and how we, as humans, see.
We need to turn to the study of physics to understand exactly how light works, and in future posts, we’ll be examining different aspects of the science of light.  For now, we’ll be looking at the Classical Order of Light.

– Classical Drawing Atelier, Juliette Aristides
Light travels in straight lines and when it hits an opaque object, such as a sphere, it will not pass through that object.  Indeed, a part of the sphere will receive light and a part of the sphere will not receive light. 
That part of the object where direct light cannot reach is the shadow.  Specifically, it is the form shadow (the shadow within that form).
Additionally, that form, our sphere in this case, is casting a shadow on another form, in this case, the ground plane, and that is the cast shadow.
These concepts are so essential to grasp and remember, it is worth repeating and internalizing them, so that we won’t confuse the shadow area with other tones on the light side that might describe undulations, furrows and other details.
The part that receives light from the direct light source belongs to the family of the lights.
The part that does not receive light from the direct light source will belong to the family of the shadows.
If in doubt about what one is seeing, it is worth testing whether a “darker” area is shadow or light.  One should first identify where the light source is located in relation to the object one is observing and use a process of logic to arrive at the right answer.  If the light source is in the top left, then it stands to reason that whatever is facing away from the light source (to the right, and downwards) would be the form shadow.  Any plane that is facing away from the light, a down plane, would most likely be part of the shadows.
A form shadow will also have a bed-bug line or terminator.  This is a boundary that completely “fences off” the perimeter of the shadow from the light.  We can look for such a bed-bug line to determine whether that is shadow or not. 
A cast shadow will be on another plane where there is an impediment, obstructing the path of the light from falling on that other plane/object.  A cast shadow will have its own outline or perimeter clearly visible.
The third test one could apply is to actually place something solid like a knitting needle in the area which one is testing.  If a cast shadow from the needle is visible in that area, then it is not part of the shadow.  If that area is indeed part of the shadow (no light is falling there in the first instance) there will be no cast shadow visible from the needle.

This photo illustrates that the shadow being cast by the knitting needle doesn’t continue into the shadow below the bottom lip.  This means that entire area under that lower lip is shadow, albeit very light shadow, including reflected light.

© Mandy Boursicot 2013


“Everything that needs to be said has already been said.  But since no-one was listening, everything must be said again.”
– Andre Gide, Autumn Leaves
Classical Drawing is a blog about the science behind the art.  It presents information for an intelligent approach to drawing.  Here, you’ll find the rationales, the explanations, the why’s and wherefore’s of what we put into our drawings and paintings.  Those things are based on what we see, and why we see them, is based on the science of light, and the study of human perception.
Anyone can achieve a high level of artistic production, given the right training, knowledge and applied practice.  This blog has been conceived as an aid to students of Classical Realism, and to any member of the public who has an interest in delving deeper into the rationales and science behind the art.
As a Classical Realist, it is my belief that drawing and painting can be taught, and can be learned, and can be mastered.  Unlike some contemporary strands of “non-skill-based art”, the art that we aim to produce is measurable against a scale of quality.  And in recent years, that standard has been increasing, the quality is augmenting, and the bar is being raised again and again.  To participate in this arena, we need to attune our eyes, and fine tune our understanding of what we see, so that we, too, can go through the steps of first drawing what we see, then drawing what we know, and finally seeing what we know.