Cast Painting at Grand Central Atelier

 I have been learning about many ways to approach modeling form in paint at Grand Central Atelier.  Since I started painting at GCA my development has been significantly aided by help from my cast painting teachers, Patrick Byrnes, Devin Cecil-Wishing and Justin Wood in addition to beneficial advice from my peer students and some helpful critiques from Scott Waddell, Will St. John and Brendan Johnston.  My teachers and peer students have so much insight they offer and I feel that I am just tapping into realization of many aspects of form painting.  I still have very far to improve with my painting abilities but this post describes some things I have learned in my development so far.

I begin the painting process by making a block-in drawing that describes linear boundaries of information on the cast.  Making a block-in for a painting is no different than creating a block-in for a drawing except that with the added difficulty of changing areas of wet and dry paint the consequences of adjusting mistakes in the block-in while painting can be more severe. So I pay close attention to specificity in the shapes while blocking-in.

The relationship between the block-in and modeling is symbiotic.  The block-in holds the modeling like the shell of an egg.  As a result, the modeling can never become more dimensional than the shape it is confined to.

Knowing that the shapes of the block-in may become slightly adjusted during the painting process I usually leave the lines in my block-ins with a slight width to make the transferred drawing on the linen easier to interpret.  With a slight width in line I also can have the opportunity to view the form boundaries as existing somewhere within that thickness of line, which gives me flexibility to determine the final shape of each form through form analysis.  This flexibility in the lines of the block-in is helpful for me because, it can be difficult to model form while being confined to the rigid boundaries of a block-in that was not completed with as in-depth form analysis that takes place during the modeling process.

Value Study

Before approaching the actual painting I create a small value study to use as an aid in managing the large relationships on the form while I later model the form in small sections.  The value study acts as a map for the value range in the cast.  By referencing the relationships in the value study I can gain a better sense of which area of my value range I should be in while working on individual parts of the cast

Underpainting

The block-in is transferred to the painting surface using an oil transfer.  This process is described on Doug Flynt's blog here.  After the block-in is transferred to the surface of the linen that I paint on, Art Fix, I complete an under-painting using paint thinned with odorless mineral spirits.  The under-painting provides coverage of the light value of the surface to create a layer that is more similar to the final values of the form painting.  If parts of the final form painting are thinner, the under-painting that is similar in value will show through instead of the light color of the ground.

I personally have preferred to keep the under-painting in a looser state to be able to clearly isolate the gradations of my modeling to make it easier for me to evaluate.  I have tried working on under-paintings that were closer in value and handling to the final form pass and struggled with evaluating the gradations as I painted because the final pass was so similar to the values of the under-painting.  Although, I imagine if I had a stronger ability to retain the conception of the overall form this difficulty of  isolating each parts gradation would not be such a struggle.  For me, the gradation is one the most difficult aspects of form to describe in suggesting the three dimensionality form.  Since I am still developing in comprehending form, I find it easier to retain the conception of one slice of a form at a time that I can easily evaluate. I currently have found it easier to manage modeling form by building the relationship of forms through focusing on developing them in smaller strip like sections at first.

Modeling Form

Form modeling in paint is essentially just drawing with paint.  The logic of light on form does not change and modeling proceeds in the same way as with graphite except with the added difficulty of controlling gradations in paint.  I proceed by creating a strip of form that suggests the curve of form as it gets lighter on its path to facing more towards the light.  It is beneficial to begin in an area that contains most of the value range on the cast, such as the darkness of a shadow to the lightness of a section of form that is most facing the light.  Although in the instance of the above image I made the mistake of  not beginning in the area where the form turned most towards the light, which made it difficult to manage relationships in the cast during the process of painting it.

For me, it easier to distinguish the modeling from the looser under-painting as if the form is a shell.  I often even imagine running my finger underneath the strip of form that I create in my paintings to see if it feels like the form should bulge out in certain areas to make the fullness of form closer to the roundness of form on the actual cast.

I create gradations in paint by dabbing a progression of values next to each other.  In areas of form that contain a broader planes I lean towards applying larger strokes of paint instead of smaller dabs.  My goal is to place small sections of value that are progressively lighter than the preceding stroke to suggest a subtle turning of form toward the light.  For each strip I often begin at the shadow and slowly crawl up the hill of form one slight change in value at a time to create a gradation that suggests the curvature of form on the cast.  I try to use thick enough paint that shows a solid value of paint with each stroke.  Due to the wet into wet nature of oil painting I can also utilize how similar values of paint blend into each other to create intermediary values but in doing so I have to remain focused on creating a specific gradation of form.  The intermediary values that blending can create are not always the specific values that describe the form.  If I do not pay attention to the effect that wet into wet blending is creating I can easily lose a specific gradation of form.

I find it important to reflect on the form consequences of each paint stroke.  I have often blended mindlessly and pretty much just blended past the values that I wanted without paying attention.   I try to remain conscious of the effect of each added value to the turning of form.  With painting it is all a matter of making precise and deliberate decisions.  Once paint is on the surface adding more paint continues to build up the surface and can make it more difficult to easily adjust the values of paint.  I have found it helpful to preface each brush stroke with the question of whether to turn parts of the form towards or away from the light.  Choosing whether to make the stroke lighter or darker. Then I just try to push the form to where I intend it to turn to. 

As the painting progresses the shell of form expands one form at a time, just as in the drawing process.  In the image above the top left form on the brow is isolated because it is not yet painted.  Because gradations in paint are much easier to adjust while wet than when dry I have been taught about the benefit of completing an entire form during each painting session to avoid significant seams in the middle of forms.  I also use a soft brush to drag the paint along the border of the boundary of each form that I complete during a session to provide a valley for the paint during the next session to attach to without the harsh border of thick paint.

With the top left form of the brow painted in I am still progressing with the painting of the eye.  An image of the completed painting is below.

Brushes

I have learned from Devin Cecil-Wishing that brushes can be shaped differently to make it easier to adjust gradations in specific ways. I have mostly been using cheap synthetic oil painting brushes from Blick Art Supplies that can get a sharp point and have substantial spring to assist in controlling each paint stroke or dab of paint.

 Pointy brushes can be helpful for adjusting tiny areas of a gradation that require more precise control.

These same brushes can be patted down to create a flatter surface area that can be helpful in adjusting larger areas of a gradation.  I have found that the size of brush to use is in relation to the size of the form and the area of a gradation that is being modeled.  Devin Cecil-Wishing has also taught me the benefits of using multiple brushes for lighter and darker areas to limit the contamination of values that occurs during wet into wet painting.

A large very soft brush can be helpful as a final touch to a section of modeling to blend away surface ridges of paint that have accumulated in the modeling process.  I usually only use a large brush at the very end of a painting session for that purpose.  Even while trying to remove those surface ridges at the end I remain conscious of how I may be adjusting the form and try to keep the form in mind as I blend.

During the modeling process I initially try to place each value of paint in the gradation as specifically as I can and then adjust the form by adding more paint to alter the value.  When I find that adding more paint leads to significant building up in the thickness of paint I often use a brush with little or no paint on it to try to bend the values into where I want them to be on the form.  Since I still don't have very much control of paint, I have found that changes in adjusting wet paint often requires some back and forth work of adding paint and blending to bend the form to a desired curve.

 Paint Use

 My teachers have emphasized the importance of using a substantial amount of paint to make it easier to manipulate.  I have found that with more paint on the surface I can adjust my gradations while limiting the amount of paint that I am taking off of the surface with my brush while making adjustments.  Painting too thinly was a serious issue that I especially struggled with on my first cast painting of the ear. I was painting so thinly that the color of the white ground significantly showed through my painted layer and created a surface that was very uneven.  Also, since I did not do an under-painting for my first painting of the ear the value of the white ground was drastically different from the values in the form pass which made the unevenness even worse than if I painted thinly on an under-painting.

 I am still struggling with controlling paint but these materials and techniques that I have been learning are helping out.  I am striving to create form in paint that suggests very specific curves of form and am still struggling with controlling the evenness of my gradations.  I often get distracted by the desire of creating a smooth surface and lose a tactile sensibility to the form modeling.  I have found it more helpful to remain focused on gaining a tactile sensation of creating from that I can believe is three dimensional and making the best decisions I can with my painting materials to sculpt the form to that effect.   When I am in that state of mind I find that as a result my form modeling becomes smoother by being more specific to the curvature of the form.

Painting Process

Value Study

Underpainting

 Reworking

 After initially completing the painting form by form I selected a few areas to improve upon during the reworking stage.  One area that I wanted to adjust was the overall roundness of the chin.  I wanted to turn the bottom planes of the chin more away from the light so that it would be more opposed to the direction of the more light facing planes on the upper chin.  I have found it important to determine exactly how I want to adjust sections of form before beginning the reworking stage to make it easier to proceed with focus.

I have been taught to begin the reworking stage by applying a small amount of retouch varnish over the entire painting to bring back the gloss from areas of the painting that have sunken in.  When reworking, I add just a bit of Oleogel to my paint to slightly thin my paint where necessary. But in areas that require significant lightening or changes I end up using paint without medium.  In areas that require significant changes in reworking, such as the chin, I ended up repainting the entire form to provide a more unified surface quality.  I proceeded by selecting a section of form to adjust and tried my best to make decisions based on how I want the form to change as opposed to making rapid decisions based on pure optical judgements of value.  By validating my decisions with form analysis I can proceed with the same amount of care in trying to create specific gradations of form as I had in the initial form painting.  Being that specificity of form is an important goal for me, I try not to lose that focus while reworking.

I learned a lot while making the cast painting shown above.  I have so much more to learn as I progress with my current cast paintings at Grand Central Atelier.

Copying at Metropolitan Museum of Art

Classical painting is a visual language in and unto itself and requires me to study how to interpret and design visual information.  To become better acquainted with the creation of classical art I have been studying from masterpieces at the Metropolitan Museum of Art in the past few months.

After William Bouguereau's painting Breton Brother and Sister

After Carpeuax's sculpture Ugolino and His Sons

While I find viewing artwork that I admire very helpful, I also often find that I look more carefully while copying from pieces of artwork.  These studies have enhanced my understanding of representing form and inform aesthetic choices that I make in my studies at Grand Central Atelier. Studying from paintings allows me to study paint application and form modeling while many of the sculptures I have copied provide an opportunity to select viewpoints of poses that I find engaging and display crucial choices made to model forms in a way that is both realistic and beautifully expressive. 

After Randolf Roger's sculpture Nydia, the Blind Flower Girl of Pompeii

After Domenico Pieratti's sculpture The Youthful Saint John the Baptist (with an imagined background)

Furthermore, these copies provide a platform for ideas of the type of art that I am interested in creating.  With a better realization of what makes me connect with amazing works of art I can strive towards aligning my work towards the aesthetic of the works that I admire.

Phases of Vision

 The process of representing what is seen involves recognizing the phases of visual interpretation. Although at first glance one can clearly recognize an image of a face as a portrait, the task of describing the visual information that makes up a portrait is much more difficult to do in an instant.  Even though we are presented with one unified visual image it can be described as consisting of individual parts, a subject that Brendan Johnston has described to us first year students at Grand Central Atelier.  In the simplest sense, what one sees consists of shapes, values and colors.  In the block-in those shapes undergo rounds of investigations to arrive at an understanding of the qualities of shapes.

As a first year student at Grand Central Atelier I have been practicing figure block-ins with the aid of my teachers, Brendan Johnston, Patrick Byrnes and Josh LaRock.  They have shared advice with me on an efficient approach to the block-in process that has been passed down through the teaching of Jacob Collins and other instructors.

The visual shapes one sees are inevitably tied to the structures that they are made of, such as the shape of an eye in shadow.  But this symbolic association of an eye in general can distract one's interpretations from observing the particular qualities of each shape.  Learning to see shapes in their purest and actual sense can be at first approached by breaking its line segments into the most clearly observed pattern.  Although the simplicity of the drawing in this stage may seem overly basic, the lines at this stage represent what I know about the shapes from initial investigation, a subject that Brendan Johnston has discussed with us first year students often.

 By the next phase of shape investigation I am  continuing to search for the specific qualities of shapes.  Although it is often tempting for me to declare that shape investigations are over early in the drawing process and launch into refining those shapes, this has often led me to represent symbolic generalizations of the structures that the shapes describe and has led to drawings that look less like the visual images that I see. In order to remain aware of the particular qualities of shapes requires an active openness to searching out the subtleties of each shape in the block in.

I had a discussion with Patrick Byrnes about what can help to retain an open awareness to the specific qualities of shapes and learned about the importance of searching for the exact shapes through constant questioning of all the shapes together.  Through continuing to question the particular qualities of shapes on the visual image the block-in becomes more clearly revealed.  The more the shapes are questioned through investigations the more truth is revealed in the answers found.

 After thorough investigation into the shapes, the block-in progresses by evaluating how the shapes correspond to the three dimensional structures they represent.  I  heard Josh LaRock comment on the importance of realizing when to switch to evaluation of  structures to develop a block-in past the shape phase.  Through interpreting each tilt of a shape as a segment of a plane as it corresponds to perspective and light effects, such as terminator and cast shadow edges, I could arrive at a more clear representation of the visual information that at first glance I actually was so unfamiliar with.

Below is an image of another portrait block-in drawn at Grand Central Atelier made using the same process.  Images of this process on figure drawings can be seen here.

Thank You

Thank you so much to everyone that was able to make it to the Salmagundi Junior & Scholarship Members Exhibition.  I really appreciated the support and met so many great people on the opening night.  I am also thankful to the Salmagundi Club for the generous award that I received for my drawing "Marie", shown below.

The exhibition is on display at the Salmagundi Club (47 Fifth Avenue, NYC 10003) until January 15th with gallery hours of Monday - Friday, 1 - 6 pm, Saturday & Sunday, 1 - 5 pm.

Taking Time

Looking at the point of my pencil, it never ceases to captivate me, the idea of how refined form can possibly become if represented to the precision of that fine tip.  Such wonder lead me through creating this eye cast drawing to investigate the subtleties of form at Grand Central Atelier.  My drawing proceeded by taking time to carefully construct gradations that represented specific curvatures of form one section of form at a time.

While  making deliberately constructed sections of form allowed me to closely study each forms specific surface, I also had to consider those smaller aspects in relation to the larger forms on the cast.  With this drawing I noticed I was able to develop more of an ability to retain a sense of the structure of larger forms while making smaller changes to them.  Since I put careful thought into the structure of each form as I constructed them, as I refined the form I could gain a better sense of where I wanted the form to develop and which areas that needed to conform to the specific curve of form I intended to make.  However I often lost sense of the larger forms while working on smaller aspects, such as sub-forms like the folds in the eye brow.  A critique from Scott Waddell showed me how to evaluate the form in the simplest possible way in order to regain a sense of the hierarchy of larger forms to the smaller forms that sit on top of them.

While progressing with this drawing I developed more of an appreciation for the idea that the smaller forms only gain significance when in their proper relation to the larger forms that they depend upon.  Working in a slow form by form method can sometime cause loss of awareness to the integrated nature of form.  But I found that the more time I spend practicing to retain a sense of where I am modeling in relation to the hierarchy of the overall form of the cast I can develop a better sense and ability to properly place smaller forms and larger forms.  I will continue taking time to carefully study form with my upcoming cast projects.

Thanks so much to the great help from all of my teachers for cast drawing, Devin Cecil-Wishing, Patrick Byrnes, Scott Waddell and the teachers who sometimes came by to help and encourage me with my drawing, Josh LaRock, Jacob Collins and Colleen Barry.  I couldn't ask for better instructors.

Thanks again to all who supported my art material fundraiser for school (The Arthur Haywood Education Initiative).  I am very fortunate to be learning so much with the supplies.

A week at the Grand Central Atelier

To offer some insight into my daily experiences at the Grand Central Atelier I am sharing a post that describes a recent week at school that was very helpful for me.

Classes for the core program are in session from 8:30 am - 5:00 pm.  As a first year student I draw from the cast in the morning until 12:30 before having lunch in the school's kitchen through 1 pm when I return to the cast hall to practice block-ins until 5 pm.

Near the beginning of the week I received valuable advice one of my cast drawing instructors, Patrick Byrnes.  In my drawing the light indentation on the eye initially suggested more of a scoop than was actually apparent on the cast.  Patrick informed me of how to more accurately describe that area by slightly lightening the darker part of the form to turn the form more towards the light. While I draw my cast during the weekday mornings I also usually can overhear the advice from instructors, Jacob Collins, Ted Minoff, Will St. John, Josh LaRock and Scott Waddell as they teach the 2nd through 4th year students in the figure room,  and from Tony Curanaj in the still-life room on some afternoons.

One day a week in the afternoons, first year students sculpt copies of casts in clay.  My sculpture teacher Zoe Dufour has been helping us with sculpting. I am sculpting from the same eye that I draw from in the mornings. A picture of us working on cast sculpture can be seen on the GCA instagram page here. This practice has helped me to gain more of an understanding of the three-dimensional nature of form and encourages me to apply sculptural considerations to assist me in modeling form more specifically while drawing in graphite.  Since drawing at GCA is approached through the concept of turning forms darker in relation to how much form turns away from the position of the light source, drawing is essentially sculpting with pencil.

When Devin Cecil-Wishing, one of my cast drawing instructors, came by the cast hall I was about to begin modeling a new form.  I was initially planning to model the lower form underneath the eye, (and a strip of form can be seen where I started working in that area) but after Devin's recommendation to model the lower brow I decided to model that form.  Since the form of the lower brow is connected to a shadow edge it is easier to make a gradation out of that shadow.  Also, it was helpful advice from Devin to move to the forms above the eyelid since they are more curved than the forms below the eye, which allows for an easier task of modeling form where the curvature of form is easier to see.  Since the cast hall is lit by light coming through a large window some of the forms on the cast that are not as round appear even more subtle under the natural light.

Later in the afternoon I took a break from practicing block-ins to see the work in progress from Colleen Barry's stucture drawing class.  It was very informative to see the work 3rd and 4th year students were making in that class and to learn about how they were approaching figure drawing through discussions with them.  The information I have been learning about the figure and form has been beneficial to me while I work on a portrait commission painting after school during the week nights.  One night one of the cast drawing instructors, Justin Wood, was able to stop by the studio in the school that I was working in and offered some very helpful advice on how I can reference master paintings to assist with painting my portrait commission.

Later in the week while I was drawing my eye cast in the cast hall, I could hear the echoes of Scott Waddell's advice in the morning coming from figure studio.  I decided to take a break from my drawing to see how the 2nd year students were progressing with their figure drawings.  I was amazed to see how refined their drawings were turning out during the second week of their month long pose and gained insight into how they pace themselves on their drawings.

During my lunch breaks I have been working on master copies while I eat.  Anthony Baus has an incredible library that he left the school in his Perspective Lab.  I have been utilizing some of his books to make master copies, such as the Carracci copy shown above.  These studies from 17th century artists has given me insight into how I can develop my own compositions, such as the one shown above on the right.  On my way back from lunch I walked past the gallery within GCA, Eleventh Street Arts, and was very inspired by the still-life show on view.  With a greater sense of how my studies are leading to more expressive works of art, off to the cast hall I returned to practice block-ins for the afternoon.

A 4-hour "tippy cast" block-in completed during an afternoon.

My cast block-in instructors, Brendan Johnston and Scott Waddell, come by during the week to give us 1st year students very helpful advice on how to approach making proportional drawings, called block-ins.  Now we are working on the practice of "tippy casts".  With this exercise we tip the casts at various angles that make the object less recognizable.  Through representing the shapes students can develop the ability to accurately copy shapes that are seen, without being influenced by the idea of trying to make a drawing that leans towards the symbolic idea of what one expects a face to look like.  While Scott Waddell and Brendan Johnston are in the cast hall I am also able to benefit from hearing the painting advice they give to the 2nd year students who are working on cast painting and I can watch as they demonstrate painting techniques on student's cast paintings to clarify how to model form.

One afternoon Josh LaRock was nice to stop by the cast hall to help us out after he finished teaching the 3rd and 4th year students in the figure room. While giving me advice on how to adjust my block-in, shown above, he suggested that I would benefit from approaching setting up my cast differently the next time.  The cast that I was blocking in did not have large unified light and dark shapes due to how I positioned it to the light and the angle that I was viewing it at.  Practicing tippy cast block-ins with a cast under a stronger lighting effect would make it easier to draw.  Josh's advice made sense to me that the practice of comparing shapes is easier to manage when the shapes are split into large and obvious light and dark shapes.  Later that afternoon I could hear some excitement from the figure room that the 3rd and 4th year students were painting in and stopped by to find that they were remarking on a figure painting that Josh LaRock brought to the studio.  Viewing the amazing figure grisaille painting of "Sheena"  that he made while he was a 2nd year student at GCA left me feeling so inspired and lucky to study at GCA.

By 5 pm  the ringing of the timer from the figure studio sounded and I could hear the 3rd and 4th year students thank the model for posing.  With that, the weekend has just begun, with more tales from the Grand Central Atelier to come when this cast drawing is done.

In progress...

Thanks again to all who supported my art material fundraiser for school (The Arthur Haywood Education Initiative).  I am very fortunate to be learning so much with the supplies.

Benefits of Master Copies

Practicing master copies has been extremely beneficial to developing my artistic voice.  Not only do these studies offer in-depth research into the effects of light, but they also clarify ways of portraying reality from the greatest masters of translating nature.  Each of these drawings, shown below, has fostered an awareness of aesthetic concerns that I am interested in.

After Ingres

After Bouguereau

Drawing of a sculpture from the Philadelphia Museum of Art

After a Carpeaux sculpture (quicker studies such as this and the one above offer a lot too)

Drawing Copy of a terracotta sculpture by Benedetto da Maiano

After Scott Waddell

     Furthermore, no matter how realistic each master's technique that I studied was, investigating the unique decisions they made revealed their representation of each subject's character and beauty.  Studying nature has been able to teach me much, but there is also great opportunity to discover what beauty is and the choices needed to be made to portray it and each subject's character by studying from the masters.

Studying the Color of Skin and its representation

The color of flesh that one perceives is caused by multiple processes of light reflection.  Diffuse reflection, specular reflection and subsurface scattering contribute to the perceived color of skin.  Through studying how light's interaction affects the color of skin I was able to use that information as a basis to paint skin.

Diffuse reflection occurs when light rays projected from a light source reflect at various angles from its meeting with the surface of a form.

The example above shows only a fraction of the portion of light rays emitted from a light source.  In diffuse reflection, millions of light rays, composed of photons, are projected from the light source to meet the surface of a form and then reflect at various angles.  The diffusely reflected light rays enter the eye at varying levels of brightness to create an image of a form under a light source(s).  This causes the form to appear darker as its surface turns away from the light.

Specular reflection is the mirror-like reflection of light on a smooth glossy surface where the angle of incoming light projected in a single direction from the light source, the angle of incidence, is reflected at the same angle into a viewer's eye, the angle of reflection.  Therefore, the angle of incidence equals the angle of reflection. Specular reflection is only visible on a form at the halfway point between the angle of incidence and the angle of reflection into a viewer's eye.  Many specular reflections create a highlight area.

Subsurface scattering is a process of light reflection where light penetrates the surface of a translucent object and is scattered by interacting with the material before it exits the object from a different point than it entered from.

Diffuse Reflection (light ray does not penetrate the surface),  Subsurface Scattering (light ray penetrates the surface)

On human skin this interaction of subsurface scattering allows for the reflection of the sub-dermis hue (the color of flesh and blood) in its combination with the epidermis hue.  While subsurface scattering occurs at various levels of light intensity, this effect is heightened in the presences of a great deal of light.  A hand placed over a flash light emphasizes the effect of subsurface scattering. 

The light penetrates through the outer layer of skin to interact with the reddish color of the sub-dermis before the light exits the surface, in this case on the other side of the light. (4)  Because the epidermis (outer layer of skin) is translucent it can be thought of as a veil through which we can see some of the layer underneath it.

Human skin is made up of many layers and each has its own properties.  The epidermis is the outer layer of skin and primarily exhibits diffuse and specular reflection.  Lights interaction with the sub-dermis of skin (flesh and blood) primarily results in subsurface scattering.  Blood is partially made up of red blood cells, composed of hemoglobin, and its properties contribute to the reddish hue perceived in the color of skin.

Human red blood cells magnified 1000 times (2)

 When light interacts with skin some light rays are absorbed or reflected from the color of the epidermis while some light rays penetrate through the epidermis and interact with the color of the sub-dermis to be absorbed or involved in subsurface scattering before exiting the surface.  Some light rays penetrate even further to reach the bone layer.(1)

All of these interactions that light has with skin creates a specific effect on the perceived color of skin.  Due to the multi-layered process that creates the color of skin, I attempted using a layered painting process to try to represent the color of skin and the effects of light that make it visible.  I experimented with this process on a painting of  an ear and will use that painting to illustrate the thought process that I have been following.

Applying  Light Concepts to Painting

The interaction of light with a painted surface involves diffuse reflection and subsurface scattering as well.  Some light rays interact with the opaque layer of paint on the surface while some light rays continue to penetrate the surface to the color under-layer and then to the color of the canvas before light is reflected from the surface of a painting, producing a combined effect of each layers color.(3)

With these properties of light's interaction with paint in mind, I experimented with representing the color of skin through its light effects in my painting.

I began by making my under-layer reddish in hue to represent the sub-dermis layer of skin.  This layer was painted thinly to allow for light to pass through it before reflecting from the canvas layer.

Then I more opaquely painted the color of the form as I perceived it.  Due to the opacity of the painted layer, it was able to reflect light more diffusely (representing diffuse reflection in the epidermis of skin), while still allowing for light to pass through it to also reflect the more reddish hue of the under-layer (representing subsurface scattering in the sub-dermis of skin).  And the color of the canvas in combination with the amount of light passing through its surface contributed to the luminosity of the color that is ultimately reflected from the painting as light rays exit the surface with properties of the layers that it has interacted with.  This painting seemed to have more of a glow than my other pieces where I used a different process.

3-D Modeling Layers

This painting process was largely inspired by investigations into 3-D modeling.  Many 3-D modeling programs separate the effects of subsurface scattering, diffuse reflection and specular reflection into different layers before representing their combined effect.  The consideration of each specific effect of light contributes to stunning representations of human skin.

Image from David Moratilla

3-D modeled image from David Moratilla

Image with no subsurface scattering on the left, compared to being shown with subsurface scattering on the right

 (5)

While the painting process described in this post is just an experiment, I am not sure how effective it has been at representing the color of skin, especially in the photograph shown, but these investigations are something for me to continue experimenting with or at least thinking about in the future.  There are many other factors that could be considered to specify the effect of the process, including the specific amount of blood in a given area, the properties of melanin in a given area, the density of hair on skin etc., and each factor could alter the painting process to produce more specific results.  So I look forward to continuing investigations with painting skin.

References

- (1) Blevins, N. (2006, June 12). Translucency and Sub-Surface Scattering. Retrieved July 15, 2015, from http://www.neilblevins.com/cg_education/translucency/translucency.htm

-(2) https://commons.wikimedia.org/wiki/File:Humanrbc1000x.jpg

- (3) Gamblin, R. (2003, October 1). Why Classical and Contemporary Paintings Look So Different? Retrieved July 15, 2015, from http://www.gamblincolors.com/newsletters/studionotes12.html

- (4) https://en.wikipedia.org/wiki/Subsurface_scattering#/media/File:Skin_Subsurface_Scattering.jpg

-(5) http://www.gamedev.net/topic/585052-real-time-skin-shader/

Many of these concepts of light are explained in further detail on Doug Flynt's blog and in Scott Wadell's video webisode here.

Canvas Preparation

I used a certain process to prepare the surface of the canvas for a commissioned portrait painting that I am currently working on.  The dimensions of this painting are life-size so I had to stretch a large  canvas.  I used an unprimed Utrecht medium texture cotton canvas for this surface. 

To prevent the stretcher bars from bending as pressure would later be applied from stretching and preparing the surface of the canvas I used cross bars (that I used from a store bought canvas that I previously had).  These cross bars were either nailed or screwed into the frame of the stretcher bars.

After the canvas was stretched I applied a layer of acrylic gesso, using the Golden brand of gesso.  This layer was applied by laying the gesso on the canvas with a brush and then using a roller, in a perpendicular direction to the brush strokes, to flatten out the texture of the surface.
     The surface was then sanded with a 220 grit sandpaper and the process was repeated twice. Once much of the space between the strands of fabric on the canvas were filled in with gesso from using the roller, I used a process to make the surface much smoother.

I first applied a large viscous amount of gesso to the surface using a brush.  Then I quickly used a plastic taping knife, shown below, to drag the wet gesso across the surface while trying to hover over touching the previously dried layer of the canvas in an effort to create a smooth surface.

This process of using a plastic taping knife is somewhat similar to laying down an area of concrete.

Once the surface had been flattened with the plastic taping knife, I proceeded to sand the dents and irregularities and out of the surface with a 320 grit sandpaper.  This part of the process took a very long time.  Part of the cause of this was that the plastic taping knife that I used did not have rounded edges for the corners of the tool, which I prefer to use.  The sharp edge of the tool that I used caused it to dig into the wet gesso as it was dragged across the wet surface.  I repeated the process with the plastic taping knife and sandpaper twice to smooth the surface for painting.

A small part of the surface shown on the left, next to the unprimed texture of canvas shown on the right.

Then I transferred the drawing to the surface using an oil transfer method (Doug Flynt explains this process on his blog here).  The process of surface preparation that I used created a much smoother surface to paint on than the texture of the canvas that I started with and was much cheaper than using a large amount of expensive linen.