Exploration of a Sphere Part 6: There is a Point

Now I am going to bring the sphere series to a close with examples of what we have been talking about from one of my paintings:

Seneca, Jaime Cooper, courtesy Patricia Hutton Galleries

Click on any image to see a slide show.  I have picked just a few examples, there are many more in there.

Exploration of a Sphere Part 5: Painting the Sphere

Yesterday I discussed kinds of edges.  Now we will discuss how I actually painted the sphere.  I try not to torture my students (too much), so I generally let them trace a circle.  I want them to learn to control the paint, values, and edges, not be stressed about drawing a perfect circle.  It turns out that the line disappears under the paint so quickly that they wind up having to paint a perfect circle anyway, but letting them trace one takes some stress out of the start. 

In his Lives of the Artists, Vasari relates the following story:

This courtier, coming in order to see Giotto and to hear what other masters there were in Florence excellent in painting and in mosaic, talked to many masters in Siena. Then, having received drawings from them, he came to Florence, and having gone into the shop of Giotto, who was working, declared to him the mind of the Pope and in what way it was proposed to make use of his labour, and at last asked him for some little drawing, to the end that he might send it to His Holiness. Giotto, who was most courteous, took a paper, and on that, with a brush dipped in red, holding his arm fast against his side in order to make a compass, with a turn of the hand he made a circle, so true in proportion and circumference that to behold it was a marvel ... Wherefore the Pope and many courtiers that were versed in the arts recognized by this how much Giotto surpassed in excellence all the other painters of his time.

Apparently people practice perfect circles as a hobby:



Link to original video.  Pretty cool.  Anyway, back to our circle.

I first did an underpainting in raw umber thinned with turpenoid.  You can still see the underpainting in the background and the reflected light at around 5 o'clock on the sphere.  Notice how the color of the thinned raw umber leans towards a warm yellowish.  I then used raw umber mixed with zinc white to do the modeling on the sphere and a bit in the background.  Notice how the white cools the raw umber and it takes on a grayish bluish cast.  When painting I paid attention to the light, especially the core shadow and reflected light, the cast shadow, and the edges.

Exploration of a Sphere Part 4: Kinds of Edges

Yesterday I discussed how cast shadows behave.   Today we are going to talk about edges.

Click on the image to see a bigger view so you can really see what I am talking about.  No matter how good my shading and value structure are, my object will still look flat if I don't vary my edges.  It is the interplay between hard and soft edges, lost and found, that make an object appear three dimensional and like there is space and atmosphere surrounding it.  Edges have overlapping characteristics which I will attempt to define here.  Please ask in the comments if I don't make this clear. 

Lost edges are edges that are either so soft and fuzzy, or the object and background are so similar in color and value, or both, that you can't clearly distinguish exactly where the object stops and the background begins.  Found edges are edges where the contour of the object is so crisp, or the color and value of the background and object are so different, or both, that you can clearly see exactly where the object ends and the background begins.  You can use these properties: lost and found, and hard and soft, in conjunction with each other to control your edges.

For example, an edge can be soft (ie fuzzy) but be a different value and/or color than the background so it is a soft but found edge.  If you superimpose a clock face on the sphere you can see this at about 8 o'clock.

An edge can be soft and lost as you can see at about 11 o'clock.

An edge can be hard and found as you can see at about 6 o'clock.

Can an edge be hard and lost?  Sure.  Check out this image: 

Depending on how you tilt your screen, the rectangle may appear black, or you may be able to just see the ghost of a butterfly.  The butterfly is black, the background is just this side of black.  The edge is definitely hard, because I drew it in photoshop.  The values and color are so close that, even though the edge is hard, it is also hard to find (ie lost).

Exploration of a Sphere Part 3: How Cast Shadows Behave

Yesterday I discussed core shadows and reflected light.  One of my students asked a really good question about reflected light, which I answered at the bottom of the post here.  Today I am going to discuss how cast shadows behave.

Did you ever paint an object which appears to float?  That is because you haven't painted its cast shadow.  Did you ever paint an object which appears to be falling off the canvas?  That is because you have the angle of the cast shadow wrong.  (I know the sphere above is rolling down hill, but that is because I can't hold my camera straight.  I swear it is straight in real life.)  Did you ever paint an object with a cast shadow, but it still doesn't seem to be firmly planted on the surface it is sitting on?  That is because the cast shadow is not quite dark enough right up against the object.  Did you ever paint a cast shadow which appears instead to be a hole down which your object is going to fall, instead of a shadow?  That is because you got the value of the shadow too dark and too even and the edges too evenly hard.

Cast shadows are darkest right up against the object and they get slightly lighter in value as they move away from the object.  Sometimes they will have reflected light in them too.  The light comes from the main light source, hits the table, bounces back up onto the sphere and creates the reflected light on the sphere.  But look closely, sometimes the light is strong enough to continue its journey, bouncing off the sphere and back into the cast shadow.  Yikes, I know, you have to look closely.

Edges of shadows tend to be harder/sharper closer to the object casting them and get softer/fuzzier as they move away from the object.  I will talk some more about edges tomorrow.

Exploration of a Sphere Part 2: Core Shadows and Reflected Light

Yesterday I started my series on the simple sphere.  Today we are going to discuss core shadows and reflected light.

The core shadow is the darkest part of the object.  It is the area that misses receiving most of the light and runs just past what you would call the light side of the object.  It appears to be the darkest part because it is also not receiving any reflected light.

The reflected light is light that falls on the table and reflects or bounces back up onto the dark side of the sphere.  It creates a bit of light on the shadow side.  This light is darker than anything on the light side of our sphere.  You know when you are a kid and you hold a dandelion up under your chin to see your chin turn yellow?  That is reflected light.  The sunlight hits the dandelion and reflects off it up underneath your chin.  The next time you are out in bright sunshine look at the plane underneath everyone's chin.  If they don't get mad at you for staring at them, you should see the color of their shirt reflected up onto that plane.

Our brains are very trained to look for this reflected light in order to interpret an object as being three dimensional.  Even people who have no idea what reflected light is will look at an object painted with reflected light and say it looks more real and three dimensional that an object painted without it.  Look very hard for reflected light and get it into your shadows.  Invent it if you have to.  Remember though, it is still darker in value than anything on the light side of your object.

Exploration of a Sphere Part 1: Types of Shadow and Light

One of the most basic core doctrines of learning to paint in a representational way is to learn how light behaves and how to paint it.  Enter the good old sphere or egg.  Now art schools make students draw or paint them until the students run away screaming.  The problem is that students are never taught the point to all this boring work.  The students are just annoyed by what they think is busy work.  So I am going to do a week long series on our simple friend the sphere to attempt to explain the point.  Every object in existence that you may want to paint can be split up into combinations of spheres and planar shapes (like a cube).  It is as simple as that.  I will do a post in the near future illustrating this point.

But first, before we can combine simple objects into more complex ones, we need to understand how light behaves when it falls upon a simple object, like our good old sphere:

I set up a wood sphere on a piece of paper with a desk lamp lighting it from the side.  This is what is termed "form revealing" light.  This light creates a clear distinction between light and dark on the sphere, thus revealing its shape.  If we moved the light around so it was shining directly on and from the front of the object, it would reveal no shadows (think a picture taken with a flash).  This would flatten our sphere out so it looked like a paper cutout.  We want to make things easier on ourselves, so we want to use form revealing light.  Think chiaroscuro or Rembrandt lighting (more about this in a later post).

Rembrandt van Rijn, Self-portrait, c. 1629; Germanisches Nationalmuseum, Nuremberg

See the strong difference between light and shadow?  This is form revealing light.  Anyway, back to our sphere, which we want to also be lit with form revealing light:

Under this lighting we can see:
a highlight
the core shadow
the reflected light
and the cast shadow

The highlight is fairly obvious, it is the lightest part of the sphere, where the strongest light is directly hitting it.  More on the other kinds of light and shadow tomorrow.

***

One of my students asked:
I was reading your blog (loving it) and I have a question on the figure painted by Rembrandt.  Is there reflective light under the figure's left eye? Thanks. 

Ooo, good question!  As the reproduction above looks, the answer could be yes.  It is darker than any of the lights on the light side of the face.  However, from my experience looking at Rembrandt lighting, that triangle under the left eye should be lighter.  It is illuminated by the main light source falling on the left cheek, not light being bounced off something.  You can just see the shadow cast by the nose on the left cheek, which ends before the triangle of light begins.  I suspect that the image above is not a great picture.  Rembrandt's paintings are notoriously difficult to reproduce.  I went looking and lo and behold:

Rembrandt van Rijn, Self-portrait, c. 1629; Germanisches Nationalmuseum, Nuremberg

That is better.  So the answer is no, that triangle under his left eye is direct lighting (but reduced a bit because it is further away from the light source).  The reflected light on the left side of his face is that bluish greenish gray tinge you see along the edge of his cheek, jaw, and under his chin.