Criticisms and answers

This Post provides a link to “Chapter 12 : Criticisms and answers“, the last chapter of my book “Drawing with Feeling“. It is a short chapter which focusses, first, on possible critiques of the ‘feeling-based‘ method advocated in the drawing lesson and, then, on my responses to them

 

CHAPTER 12 – CRITICISMS AND ANSWERS

 

A selection of drawings and paintings by students

Drawing is used for making both drawings and paintings. Below I add examples of both made by my students, all of which required the use of drawing skills. Unfortunately, I do not have examples of work they produced before being subjected to the drawing lesson. I am sorry about this because the progress made can be described as either ‘significant‘ or ‘astonishing‘. For example, there are two drawings by dyslexics who came to Montmiral with extremely limited drawing skills (One, when she arrived, was much less skilled than many seven year old children, the other was in despair that he could find no teaching that could help him improve from his current naive-adult level). I wonder if anyone can pick out the images they made. Apart from these two examples, some of the works are by complete beginners, others are by relatively experienced amateurs and yet others are by professionals. Can you tell which?

The first drawing bellow illustrates the struggles that accompany the rigorous training of the feel-system that takes place during the drawing lesson. The second drawing illustrates the immediate benefit, while the other drawings provide a small sample of the variety of ways the students used what they had learnt in the longer term.

 

The drawing lesson
The drawing lesson: An example of the lower part of a tree trunk that took two and a half hours of talk and feel-system training to get this far. Notice the multiplicity of the mistakes and corrections.

 

criticisims : first drawing after the lesson
The drawing lesson: An example of a first, feeling-based, follow up drawing, taking approximately three hours

 

Criticisms : John Hughs drawing of esplanade wall
A drawing of esplanade wall (study for a painting)

 

Criticsisms: Mary Burke down the pathway-pencil
Down a pathway (a study for a painting)

 

Criticisms : Student: portrait of me
Quick charcoal portrait of me, when I was teaching rather than posing

 

Criticisms : Student : portrait of Laura
Seated woman reading

 

Criticisms : student : Seated woman in front of Fireplace
Seated woman posing for a drawing class, in front of a fireplace

 

Criticisms : Donal Bannister : Esplanade bench
A bench on the esplanade (a study for a painting)

 

Criticisms : george hooper doorway drawing
A ancient door in perspective (a study for a painting)

 

Criticisms : Student drawing of local landscape
Drawing of local landscape

 

Criticisms : Sarah Elliott : portrait of Fen
Portrait of a young woman

 

Criticisms : Loucine Hamel : portrait of Sarah
Portrait of a woman

 

Criticisms :Marie-Thérèse Rouffignac : Self portrait
A self portrait of a woman, in watercolour

 

Criticisms : Ken Marunowsky : Montmiral vista
Looking out beyond the buildings

 

Criticisms : Sylvia Toone : Still life
Still life with yellow teapot

 

Criticisms : Gordon Frickers yellow tree in oils
Pathway and trees

 

Hugh moore farmhouse in oil
Farmhouse in countryside

 

Roger Raijanovoja : dream logs burning
Dream of logs burning

 

Sarah Moore : Sheep tracks
Sheep’s pathways abstracted

 

Eliza Conyngham girl at Puycelci with chestnut
Memory of a magic moment

 


List of links to already published chapters from the two books on drawing

VOLUME ONE : “DRAWING ON BOTH SIDES OF THE BRAIN”

BOOK 1 : “DRAWING WITH FEELING”

The chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

The chapters so far loaded:

OTHER POSTS ON DRAWING:

spacer

Go to top of page

Go to list of all other contents

spacer

The lesson: conclusion

Building on what has been learnt

Having got a feeling for using the “feel-system“, from Chapter 4 , (“The sketch and the feel system“) and experienced the challenge of making use of it when making drawings from observation in Chapter 10, (“The drawing lesson: action“) this ‘Post‘ provides a link to Chapter 11, (“The drawing lesson: conclusion“). Its role is to offer suggestions as to how to follow up and build upon what has been learnt already. In particular, an exercise is suggested that demonstrates the efficacy of the method, both for training the memory and for improving information pick-up speed without losing accuracy. With sufficient practise, these chapters on the “feel system” and its application in the drawing lesson, will enable artists to:

  • Use literal accuracy as a tool for deepening awareness of appearances,
  • Harmonise line-production with ongoing feelings.
  • Extend the meaning of “accuracy” to include any ‘exaggeration‘, ‘distortion‘ or any synthesis that reflects the “reality” of current personal experience.

 

CHAPTER 11 : THE DRAWING LESSON-CONCLUSION

 

Images and quotations

Expreesion of deep feeling
Albrecht Dûrer: Tenderness exemplified in his portrait of the artist’s Mother. As he wrote, “Love and delight are better teachers than compulsion”.

 

the power of disciplined free expressioon
Auguste Rodin : The many inaccuracies show how a deep knowledge of anatomy can energise a freedom of mark-making. In praise of the rigorous approach of his teacher, Horace Lecoq de Boisbaudran, he wrote: “what luck we had in falling in with such a teacher. Most of what he taught me is assuredly in me still”.

 

Hidden perfection
Edgar Degas : A rough looking study, but with everything in its right place. As the artist himself said, “It is all very well to copy what you see; it is much better to draw what you only see in memory. There is a transformation during which the imagination works in conjunction with the memory. You only put down what made an impression on you, that is to say the essential. Then your memory and your invention are freed from the dominating influence of nature. That is why pictures made by a man with a trained memory, who knows thoroughly both the masters and his own craft, are almost always remarkable works.” One of the best statements I know of the philosophy behind the method of Horace Lecoq de Boisbaudran.

 

The power of exaggeration
Vincent Van Gogh: “I needn’t rush – that’s no good – but I must work on in complete calmness and serenity, as regularly and with as much concentration as possible, as concisely and as pointedly as possible.” He also said, “I would like to be able to draw more freely and with more exaggeration”.

 

A lesson in the power of distortion
Toulouse-Lautrec: On meeting someone with a face that interested him, said: “Monsieur, it would be doing a great favour to me if you would come to my house and pose for a portrait. It will probably not look like you, but that is of no importance.”

 

The primacy of feeling
Pierre Bonnard: “You can take any liberty with line, with form, with proportions, with colours, in order that the feeling is intelligible” and “Impulse, which supersedes science is sometimes superior to science, which, in its turn, supersedes the impulse” and “You have to be patient, know how to wait. The emotion will surge up in its own time”.

 

A lesson in reductionism
Henri Matisse: Self portrait: “Underneath this succession of moments which constitutes the superficial existence of beings, and which is continually modifying and transforming them; one can search for a truer, more essential character” and “The effort to see without distortion takes something like courage and this courage is essential to the artist, who has to look at everything as though he saw it for the first time; he has to look at life as he did when he was a child and, if he loses that faculty, he cannot express himself in an original, that is to say, a personal way” .

 

a life lesson for all
Self portrait and a quotation from my book: “Fresh Perspectives on Creativity “: All we can do is get on with being ourselves, knowing full well that our weaknesses can be our strengths and that, even our strengths are no great disadvantage, if we don’t get too uppity about them.

 

 

Below are links to other chapters from my book, “Drawing on both sides of the Brain“, and to related material


 

VOLUME ONE : “DRAWING ON BOTH SIDES OF THE BRAIN”

BOOK 1 : “DRAWING WITH FEELING”

The chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

The chapters so far loaded:

OTHER POSTS ON DRAWING:

 

Full list of Posts in all categories

Go to top

 

The drawing lesson

The drawing lesson that can be found in Chapter 10 of “Drawing with Feeling“, is the most important chapter in my book on the practice of drawing. All the other chapters either lead up to it or hinge upon it.

The key difference between the method described in this book is that it concentrates on training our capacity for getting a feeling for relativities of length, angle and position of lines drawn on the page. The method was developed on the basis of my research findings, when I was a Senior Research Fellow in the Department of Psychology at the University of Stirling in Scotland. I was later to discover that, despite many superficial differences, my drawing lesson also has much in common with the core ideas of Horace Lecoq de Boisbaudran, the highly influential 19th century teacher. The big difference between his method and mine is that while he emphasises training the memory in a general sort of way, mine, with the advantage of knowing about important 20th century advances, emphasises the aspect of memory that deals with training the “feeling system“.

The drawing lesson in this chapter is a description of the one that I give to individual students. It usually takes about three hours of highly concentrated trial, error and in-depth explanation of why the error has been made. After it, almost everybody, no matter their original level of attainment, will find that they have taken a significant leap forward in their ability to draw from observation with accuracy. The leap forward for beginners is regularly spectacular and many, already skilful, professional artists have been impressed by the improvements in both the speed, accuracy and expressiveness achieved in their drawings from observation. Some idea of their appreciation can be obtained from the “exhibiting artists” section of the student comments page. In the next chapter it will be shown how students can build on what they have learnt and, as a result, make signifiant progress, both in drawings made from memory and in line-production speed.

While the drawing lesson and its follow-ups enable students to surprise themselves (and sometimes me as well) with the progress they make in one day, they will need to follow up with the exercises suggested in the next chapter and in various other places in this book. If they do so regularly, over a period of time, they will find themselves experiencing, over and over again, the advantages of a method that is centred upon the use of comparative looking, used as a tool for expanding awareness, and of the “sensing” of relativities, as a means of guiding line output. The reward will be an ability to create drawings, whether made quickly or slowly, that are enhanced by their new found and personalised, feeling-centred, information pick-up skills.

Converting a live drawing lesson into the written word has inevitable disadvantages, particularly when it is one that requires up to three hours of sustained concentration from both student and teacher. For this reason, however clear my explanations, Chapter 10 was never going to be an easy read. A consequence of this is that getting the most out of it may prove to be hard work. If it does, I hope that you will not let this put you off, for taking as much time as is necessary to understand and implement each and every step will be well worth the effort.

The centrality of feeling

The big differences between the method explained in this chapter and other methods are the emphases on:

  • Using accuracy as a way of extending awareness, rather than as an objective in itself.
  • Enabling liberation from widely taught methods that distance us from our feelings.
  • Sensing as a way of measuring spatial relativities (of size, length, orientation and position on the page).
  • Coordinating the information pick-up system with the organisation-of-action skills system to enable fast, information-rich results.
  • Opening up opportunities for “personal expression”, through exaggeration (Van Gogh, et al.), distortion (Toulouse-Lautrec, et al.) and feeling-connected mark-making (Bonnard, et al.)”.

Before attempting to follow the instructions in Chapter 10, it might be well worth revisiting Chapter 4The sketch and the feel system. There, beside elaborating upon what I mean by the “feel-system“,  I suggest a number of simple exercises to give you experience of using it.

 

CHAPTER 10 – THE DRAWING LESSON

 

Below you will find some images and, below them, some links to already published chapters from BOOK 1, “Drawing with Feeling” and from BOOK 2, “Drawing with Knowledge” , both from the two-book Volume that I have written on the practice of drawing: “Drawing on Both Sides of the Brain“.

 


Six rapidly drawn images in ink and pencil

Illustrating how feeling-centred, personal responses to a pose can be conveyed in the rapidly made drawings

 

Drawings of Putel

Cats doing what they do best: Creating eye-catching patterns of curvatures, and softening hearts, while lazing around

 

ink drawing of Katherine

Catching the energy of unplanned body positions that cannot be trusted to last more than a few seconds

 

Drawings of Helene

How simple lines can catch a fleeting expression or a chance pose that unexpectedly catches the eye

spacer


INTRODUCTORY

VOLUME ONE : “DRAWING ON BOTH SIDES OF THE BRAIN”

BOOK 1 : “DRAWING WITH FEELING”

The chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

The chapters so far loaded:

 


Go to top of page

Go to list of all other contents

i

 

A bridge to creativity

The bridge

The main body of my two part volume on “Drawing” is now complete. What is now required is a bridge to the volumes on “Painting”. This is provided by returning to the subject of “accuracy” as a catalyst to “creativity“.

It is common to find artists and teachers that scorn accuracy. These point out point out that all truly accurate drawings would be the same, no matter which artist produced them and that this would be the antithesis of creativity. But nowhere in any of my books is this use of accuracy recommended. What they do recommend is its use as a tool for both ‘looking‘ and ‘feeling‘ in new ways.

The efficacy of the ‘looking‘ part is easier to explain, for the search for accuracy gives us every chance of  expanding awareness. This must be the case for it requires us to adopt strategies that reveal aspects of appearance that we normally overlook.

In “Drawing with Feeling“, the first BOOK in this volume, the focus is on two inextricably linked approaches to seeking accuracy:

  • The analysis of relativities of size, length, orientation, curvature, position on page, etc..
  • The use of comparative looking to as a means of avoiding the many traps that the processes of visual perception have laid in our way.

Due to the fallibility of human judgement, neither of these can actually achieve total accuracy. But that is beside the point. It does not matter how inaccurate the result, the process of seeking it will have revealed new aspects of appearances and provide opportunities for finding out more about ourselves.

In “Drawing with knowledge“, the second BOOK in this volume, the emphasis is on using linear perspective and anatomy, not as rules for construction images, but as ways of guiding looking strategies. In other words as tools that encourage new awarenesses.

In the next two books, “Painting with Light” and “Painting with Colour“, the emphasis is on  how knowledge of light and colour-related phenomenon can help develop our sensitivity to colour in nature and extend and enrich our domains of exploration.

The idea that the accuracy aspiration might provide a bridge to the awakening of new feelings is harder to for some people to entertain. However it necessarily constitutes a voyage of discovery and, accordingly, provides a way of enriching the memory stores that link us to the feelings of a lifetime.

 

CHAPTER 22 – A BRIDGE TO CREATIVITY

 


Images to go with quotations

This chapter has a large number of quotations from artists, but no images accompanying them. I am therefore taking this opportunity to rectify this omission and add a few more quotations.

The first three come from artists that were working well before the arrival of the “Modernist Painters”, but who were significant precursors.

The emphasis is on ‘feeling’ and ‘memory’ and the implication that these is a connection between the two.

 

Bridge to Chardin
Jean-Baptiste Siméon Chardin, “Did you say that one paints with colours? Not at all, one merely uses colours. One paints with feeling.

 

Bridge to Couture
Thomas Couture (teacher of Edouard Manet), “Inferior artists fail to respond passionately to nature and merely follow it like a child tracing a picture.

 Constable
John Constable, “Drawing is just another word for feeling.”

 

Bridge to Manet
Edouard Manet, seeking the ‘effortless’ look, is known to have submitted at least one of his models to more than forty sittings. His hope seems to have been to complete his painting in one go, but he is said to have only once succeeded. Except on that one occasion, every sitting consisted of a variably long sequence of “failures”, each of which had to be scraped down ready for another try. Evidently, as one sitting succeeded another, the artist could not but help become more and more familiar with the pertinent aspects of his sitter’s appearance and this familiarity would certainly have influenced the looking strategies he used subsequently.

 

Monet
Claude Monet, “I want to succeed in expressing what I feel” and “No one is an artist unless he carries his picture in his head before painting it, and is sure of his method and his composition” and “Impressionism is nothing but immediate sensation. All the great painters were more or less Impressionists”

 

Van Gogh
Vincent van Gogh: fellow students in the Antwerp Academy were astonished to see him completing fifteen studies of the model while they were still labouring away on their first. In the Dutch artist’s view, “one drawing study on its own does not give full satisfaction, but many of them, even if they come from different sources, mutually complete one another.” He also said, “I would like to be able to draw more freely and with more exaggeration.”

 

Gauguin-still life painting
Paul Gauguin “My simple object, which I take from daily life or nature, is merely a pretext, which helps me by means of a definite arrangement of lines and colours to create symphonies or harmonies”. Also, he is said to have remarked that he closed his eyes in order to ‘see’.

 

Cézanne
Paul Cézanne was far from advocating cold objectivity when he made the statement, “The painter paints, whether it be an apple or a face. Painting is only a pretext for play of lines and colours, nothing more”. According to him “painting from nature is not copying the object, it is realising one’s sensations.” His advice was to “look at the model and feel very exactly… and express oneself distinctly and with force.”

 

Bridge to Bonnard
Pierre Bonnard, “Drawing is sensation. You can take any liberty with line, with form, with proportions, with colours, in order that the feeling is intelligible”.

 

Bridge to Degas
Edgar Degas: “Drawing is not shapes, it is one’s feelings.”  and  “It is all very well to copy what you see; it is much better to draw what you only see in memory. There is a transformation during which the imagination works in conjunction with the memory. You only put down what made an impression on you, that is to say the essential. Then your memory and your invention are freed from the dominating influence of nature.

 

Picasso
After eighty (some say ninety) sittings, Pablo Picasso felt that he had failed to complete his portrait of Gertrude Stein. However, without realising it, during his struggles, he had got to know the features of the sitter’s face so well that, after a period of reflection and gestation, he was able to produce his rendering of it from memory.

 

Matisse
Henri Matisse, “Exactitude is not the truth” and “I cannot copy nature in a servile way; I am forced to interpret it and submit to the spirit of the picture” and “I might be satisfied with a work done in one sitting, but I would soon tire of it: therefore, I prefer to rework it so that, later, I may recognise it as representative of my state of mind” 

 


Link to list of all chapters

Return to top of the page

Head movement opportunities

How head movement can help accuracy in drawings from observation

All the books correctly say that, when using the perspective frame and other traditional devices for obtaining accuracy in drawings from observation, head movement must be avoided at all costs. Teachers also warn students, who are trying to obtain accuracy when drawing from observation, that any movements of the head can substantially change both internal and external relationships in the scene they are depicting. Although what they say is true, their warning glosses over the fact that such movements can be  a powerful tool for homing in on accuracy. The purpose of this Post is to provide  the link below to “Chapter 17 – Head movement“, which explains why. Below that link I have included a slightly edited version of the Introductory to that chapter.

CHAPTER 17 – HEAD MOVEMENT

Introductory

Having learnt to find the eye-line, we are ready to make further use of the analogy of the opening window. The purpose of the next two chapters is to become better acquainted with some of the many anomalies of visual perception that regularly plague attempts at accurate drawing from observation. In this way we will learn to become more sensitive to aspects of appearances that we might otherwise overlook. Three particularly pervasive sources of anomalies are:

  1. Turning the head (whether from side to side or up and down)
  2. The imposition of axes of symmetry by our visual systems.
  3.  The constancies of size and shape.

This chapter and the one that follows give examples of each of these, which will appear under three headings: “head movement”, “axes of symmetry” and “the constancies”. Although for explanatory purposes, it is convenient to treat them
separately, we find that any combination of the three can be affecting our percep
tion at the same time. We start with this chapter on  “head movement”

Images illustrating head movement

The three images below show three different views of long boundary the wall of the esplanade. They provide a bit of realism to line drawings found in Figures 1a, 1b, 1c & 1d  in the Chapter 17, to which this Post is inked.

 

Movement
Long wall to the right

 

Head Movement
Long wall to the left

 

Head movement
Long wall head on

 


Chapters so far published from

Book 1 and Book 2 of “Drawing on Both Sides of the Brain” (Volume 1 of the series of four volumes)

BOOK 1 : “DRAWING WITH FEELING”

Chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

Chapters so far loaded:


 

Full list of Posts in all categories

Back to the top of the page

Axes of symmetry & receding surfaces

Axes of near-symmetry

I have to thank two short women and a tall man for revealing to me that “axes of near-symmetry” are intimately related to the phenomenon of “orientation constancy”. The tall man was looking over a low wall and he was depicting its top as sloping down from left to right. The short women drew it as horizontal. The fact that the man could see a particular field beyond it that the women were unable to see, meant that he was the only one of the three that was being influenced by what I later came to call the “bakery facade illusion”. The women were right that the top of the wall was horizontal. To find why the man was also right, click on the link below to Chapter 18 of my book “Drawing with Knowledge”. Its title is “Axes of symmetry, recession and the constancies”.

 

CHAPTER 18 : AXES OF SYMMETRY & RECEDING SURFACES

 


Some photos showing axes of near-symmetry and receding surfaces

 

axes of symmetry
The old bakery facade, before restoration. The axis of near-symmetry clearly slopes upwards, away from the viewer

 

axes of near-symmetry
The old bakery facade transformed into new homes. The wall top, the roof bottom and the axis of near-symmetry are very nearly parallel.

 

axes of near-symmetry
The “bakery facade illusion” in rue de a Porte Neuve. The axis of near-symmetry of the retaning wall to the left slopes up away from the viewer.

 

receding surfaces
Receding fields with vertical cypress tree as guide  to analysis

 

receding surfaces
Setting off into a receding landscape. The lowest part of the white house is not far off being the height of the walkers above  their heads

 


Click here for full contents list for both books on drawing

BOOK 1 : “DRAWING WITH FEELING”

Chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

Chapters so far loaded:

 


 

Full list of Posts in all categories

Back to the top of the page

 

Eye-line problems

Finding the eye-line

Establishing an eye-line is the first step if you are going to use the the rules of linear perspective for constructing an image. The same is true, if you are using the same rules as an aid to drawing from observation. However,  whereas its use in construction is straightforward, its use in drawing  from observation is far from it. The purpose of this Post is to explain why. Below you will find a link to “Chapter 16 – Finding the eye-line“. I have also included a slightly edited version of the Introductory to that chapter.

CHAPTER 16 – FINDING THE EYE LINE

Introductory

After the session in the studio, we move out into the street. From the demonstrations using the opening window, we have learnt that any straight edge that lines up with the eye-line remains horizontal no matter at which angle it is relative to our line of vision. If we are to make use of this knowledge, we need to find the eye-line. As a general rule, students who come to my school assume that this is easy to do, but the evidence of the drawing they make suggests that they are likely to be deceiving themselves.

 

eye-line
Making it easy to see the slope of the esplanade wall

 

Eye-line
Asking for trouble: explanation why in the chapter

spacer


Chapters so far published from

Book 1 and Book 2 of “Drawing on Both Sides of the Brain” (Volume 1 of the series of four volumes)

Contents list for both BOOKS

BOOK 1 : “DRAWING WITH FEELING”

Chapters so far loaded:

BOOK 2 : “DRAWING WITH KNOWLEDGE”

Chapters so far loaded:

spacer


Full list of Posts in all categories

Back to the top of the page

 


 

The eye in diagrams

The surprising eye

The eye is full of surprises. The biggest ones come from the structure of retina that is situated at the back of it. The purpose of this Post is to provide a link to images and explanatory captions that tell us more about this starting gate of visual processing. At first sight, much of what we find strikes us as bizarre. But, when we delve more deeply, we discover the considerable advantages of the way things actually are. It turns out that nothing would work nearly as well as it does, if things were arranged any differently. The images and their captions will go a long way towards explaining why.

In the process, they will help readers to get a better understanding of how the eye/brain combination makes practical use of the information contained in the ever-changing patterns of light coming into the eye.

The link to the diagrams

Click on the link below to access the images and captions referred to. They are extracted from ‘The Glossary‘ to the four volumes I am in the process of publishing on this website.

 

GLOSSARY DIAGRAMS (1)-THE EYE

spacer

What happens next

Upon leaving the retina, the neural signals travel in two directions. Some go up the optic nerve to the region of the neocortex known as ‘Visual Area 1′. Others take a completely different route that makes contact with the regions of the “Old Brain”. These play a central role in visual perception as we experience it. For example, they play their part in eye movements, spatial awareness, affective responses, multimodal processing, whole-field relations and much besides. Images and captions relating to both these routes will be posted later on this website, in a separate entry, entitled, “Visual Regions in the Brain”.

spacer

Images of blood vessels, neurons and and neural processes in the eye.

The human retina contains a very large number of neurons (cells) and a very much lager number of neural of processes providing links between them. It also features a dense network of blood vessels that supply blood to the neural processes. Together these three components make a significant barrier to the passage of any light that strikes the receptors. Until I learnt better, this light-blocking function did not seem to be of much of interest.

What changed my mind was the discovery that the light-sensitive cone and rod receptors that transform light-energy into neural signals, do not face towards the incoming light, but away from it. Consequently, the light coming into the eyes has to penetrate this light-impeding layer of neurons, neural processes and blood vessels, before it reaches the receptors. To add to my surprise, it turned out that the light-receiving end of the receptors is buried in a layer of dark matter. It was some time before I realised how these seemingly bizarre arrangements make possible visual perception as we know it.

The barrier confronting the light that enters the eye

It turns out that the barrier of neurons, neural processes and blood vessels compensates for the fact that the rod receptors are very much more sensitive to light than the cone receptors. The benefit of this state of affairs is that it enables a necessary degree of functional equality between the responses to the incoming light of the two different receptor-types. Needless to say, this equalling up would not take place, if the light striking the less sensitive cone receptors were to be subjected to the same impediments. This explains why the forces of evolution have created a gap in the neuron and blood vessel barrier in front of the region known as the fovea, exactly where the incoming light strikes the cone receptors.

Glare-blindness

If the equalling up process did not take place, the rod receptors would be bleached out whenever the incoming light was strong enough to activate the cone receptors. The result would be a massive degree of glare-blindness in daylight conditions.

Dire consequences

If they were effectively blind, the rod receptors would not be able to participate in daylight visual processing. As a consequence, the neural computations of whole-field relations could take place. One of the many aspects of visual processing that would rendered impossible would be the separation of reflect-light from body-colour. As a result there would be neither colour constancy, nor the use of the information residing in the  reflected-light that has been separated out.

If this were so,  pretty well all that I have written in my book “Painting with Light” would be nonsense.

Burying the receptors in dark matter

The burying of the light-sensitive receptor heads in the dark matter is easier to explain. It prevents the light from scattering from one receptor to the next and, consequently, reduces blurring.

spacer

The eye
Figure 1: Blood vessels blocking light from the ‘rod’  photosensitive  receptors.  The small darker disc is where the light sensitive ‘cone’ receptors are located. Notice that no blood vessels impede the passage of incoming light to these.

 

The eye
Figure 2: This image of a small section of a network of neural processes gives an inkling of an idea of the extent to which these these can block the incoming light.  For reasons explained above, the blockage only applies to ‘rod’  photosensitive receptors. It does not apply to the ‘cone’ photosensitive receptors .

 

The eye
Figure  3: A diagram of cell-types in each of the five layers of the retina. The massive numbers of each of these contribute to the blocking of the light arriving at the ‘rod’  photosensitive receptors.

Some numbers and sizes

One estimate for the number of the light-sensitive receptor cells is in the region of 150 million. Although the precise number of neurons and neural processes in the retina is unknown, it is certainly in the hundreds of millions.  All this packs into an astonishingly thin layer (less than 0.5 mm) whose extent can be compared to that of a 10p piece.

 

A reference

If you want a comprehensive account of the component parts and structure of the retina, you could consult the relevant pages of the website of the The National Library of Medicine.  You will find them dizzyingly more complex than the grossly oversimplified information given either above or in the ‘Glossary‘ extract.

spacer

Go to top of page

Go to list of all other contents

spacer

 

Linear Perspective : Chapter 14 :

The mixed history of linear perspective

The purpose of this “Post” is to provide the link (below) to my introduction to “Chapter 14 : Linear Perspective“, the second chapter of “Drawing with Knowledge” (the second BOOK in the two book volume).  The main subject dealt with is uses and abuses of Linear Perspective.  The chapter explains the purpose for which the rules the rule of linear perspective were developed and how over the years  artists and teachers came to use them for other purposes for which they are not suited. It also explains how the rules of linear perspective can be used in new ways. A preliminary idea of what this means can be found in  first paragraph of the “Introductory” to this chapter, which I have included below. Also see below for links to all published chapters from “Drawing with Feeling“, the first BOOK in the two book volume.

spacer bar

CHAPTER 14 – LINEAR PERSPECTIVE

spacer bar

“Introductory” – from Chapter 14 : Linear perspective

Academic tradition divides the subject of “perspective” into two aspects, known as “aerial” and “linear”. Aerial perspective concerns colour changes due to the influence on appearances of atmospheric particles situated between the eye and an object being viewed at a distance, and is dealt with in a separate volume. In this book attention will be confined to linear perspective. Moreover, to avoid misunderstandings, it is important to stress that no attempt will be made to compete with the many existing texts on this subject which demonstrate that, when properly applied, the well-known laws can enable the construction of moderately realistic images without the need to actually look at anything. As far as I know there is nothing of interest to add to these, although, a great deal needs modifying in many of the texts on the subject which regrettably give us oversimplified and therefore misleading versions of this complex and elegant subject. Rather, in this volume, the laws of linear perspective are treated in a completely novel way: not as a set of instructions for the placement of lines on but as a tool for guiding looking strategies. This transformation is achieved by placing them in the context of ideas coming both from 19th century research into visual phenomena and from much more recent discoveries relating to the functioning of eyes and brains. In PART 2, the subject of anatomy will be treated in an analogous way for analogous reasons.spacer bar

Some images relating to the theme of linear perspective

Illustrating Brunellesci’s perspective mirror set-up (maItaly : Italian History and Art)

 

Linear perspective
Pietro Perugino, Christ handing the keys to St Peter 1481-1482.

 

Linear perspective
School of Athens by Raphael in the Stanza della Segnatura 1509-1511

 

linear perspective
Albrecht Dürer – perspective device for obtaining accuracy

spacer bar

A list of  chapters from “Drawing with Feeling“, book 1 of “Drawing on Both Sides of the Brain

Chapters 10 to 13 to be published later

A list of  chapters from book 1 of “Drawing on Both Sides of the Brain

spacer bar

Go to top of page

Go to list of all other contents

spacer bar

Perspective and anatomy revisited

New ways of making use of perspective and anatomy

The purpose of this ‘Post’ is to provide the link (see below) to my introduction to “Drawing with Knowledge”, the second BOOK in the two book volume (See below for links with the published chapters of “Drawing with Feeling“, the first BOOK in the two book volume). The two main subjects dealt with are Linear Perspective and Anatomy.

spacer

BOOK TWO,  CHAPTER 13 -DRAWING WITH KNOWLEDGE

spacer

Do the rules of perspective and anatomy help or hinder accuracy?

A key property of the world we live in is that we will never perceive any of its contents as the same on more than one occasion. The list of reasons why includes the influence on appearances of:

  • The almost infinite variety of species and object types
  • The invariable uniqueness of genetic differences between members of the same species
  • Ageing
  • Environmental conditions, including  variations in the direction and strength of primary and secondary light sources, degree of atmospheric filtering, etc.,
  • Occlusions by other objects
  • Viewing angles and viewing distances
  • Visual illusions.

However seeing something (even the same object) as the same on more than one occasion is what we have to do if we are to recognise it.  This means that:

  • Recognition and the content of our long term memories must depend on generalisations
  • There will always be a degree of uniqueness in the appearance of every object we try to draw or paint from observation.

From all this we can conclude that:

  • Achieving accuracy in drawing or painting from observation will always require finding out about aspects of appearance that cannot be stored in our memories.
  • Following the rules of linear perspective or anatomy can never achieve accuracy in drawing or painting from observation.

So what can they help us to do?

  • The rules of linear perspective and of anatomy can help us construct plausible images from the imagination (See examples below)
  • The rules of linear perspective and of anatomy can help us to know what to look for.

The second of these provides the main subject matter of this book.

 

Some studies using linear perspective and anatomy.

  • Linear Perspective

perspective and anatomy
Structural study of complex object
perspective and anatomy
Piero della Francesca : studies of a head
perspective and anatomy
Piero della Francesca : Use of linear perspective in his painting “The flaggelation of Christ”

spacer

  • Anatomy

perspective and anatomy
Visalius : anatomical study from his famous book
perspective and anatomy
Leonardo da Vince : study of arm musculature
perspective and anatomy
Michelangelo : Page of studies

spacer

A list of  chapters from “Drawing with Feeling”, book 1 of “Drawing on Both Sides of the Brain”

spacer

Go to top of page

Go to list of all other contents

spacer