Wednesday, October 27, 2010

VALUE SCALE

Value scale refers to the gradual movement from Black to Gray to White. A value that is on the upper portion of the value scale is known as being “high key.” And a value that is located on the lower portion of the value scale is known as “low key.”

Arrangement of the these values, their quantities, and their shape can indicate light direction, intensity, and object tactility. A value scale drawing is bound by the number of values chosen, the more chosen, the more accurate the representation.Within a value scale drawing, boundaries between individual shape are left. This allows the value gradation to be seen clearly. It yields a graphic representation of the object.

Value scale- low to high.


A Value Finder- a tool to assist in discerning a true isolated value amidst many. This tool allows the viewer to locate the value within the viewing hole and see it unaffected. Within most complex value relationships of a subject, there is a lot of simultaneous contrast, and fluting making it difficult to see accurately. This Vale Finder is about a 5 on the Value scale- middle.



A simple cup with illumination from the left.


The same cup rendered into a 9 value scale representation. Notice the gradations along the cylinder base. Each value has shape and is progressively darker than the one to its immediate left, allowing the gradation to be seen. The gradation also informs the viewer to the surface of the object. In this case the side of the cup is smooth and curved. The rim of the cup shows a stark transition from interior light to exterior dark, this shows the surface has a dramatic plane shift. Placement, shape, and quantity, indicate how the light is falling over the surface.


This is a representation of the value scale drawing as outlines or boundaries. Value is what gives light information and adds to form.



Wednesday, October 20, 2010

ANATOMY- TRUNK

The strength of all figure drawing comes from a mixture of formal skill and anatomical knowledge. Understanding the human body, interior as well as exterior, is essential. Through out history many cultures have preoccupied themselves with depicting the human form. Western Civilization Art reached its investigative height during the Renaissance, also a coinciding focus of science and art. Below is an example of Leonardo DaVinci's Vitruvian Man. This is a clear demonstration of the need to make sense of the human form- in this case the perfection of human form and its relation to the perfect language of Geometry, the perfect circle and square. The figure is inscribed with its proportions measured and reach touching these shapes. Also note Leonardo's proportions for the figure using the measure of a head.

In 1747 we see the example of one of the most accurate representations of the human skeleton in the work of Bernard Siegfried Albinus- Corporis Humani. The following three examples are taken from Drawing Lessons from the Great Masters, Robert Beverly Hale. Here we see the human skeleton displayed not as static, but as if in motion. All bones and structures are presented in fine proportion, accuracy and rendering. Of specific interest is the TRUNK, or the area composed of the Cage and Pelvis. Please note the volume and form of each of these structures and how the artist represented them using line and value. Below is the Ventral position.

The Dorsal Position.

The Lateral Position.

The following four examples are taken from Human Anatomy for Artists by Andras Szunyoghy and Dr Gyorgy Feher. Below is an example focusing on the trunk. Note the relationship of the shapes, proportions, and location of the cage and pelvis. Also see how the top of the cage tapers and slips up into the shoulder girdle (a horizontal ring composed of the clavicles and scapula.) Notice the hollow in the pelvis as it completes the volume of the cage.


Below is an example of just the Cage (or Thorax.) It is important to note the volumetric shape of this structure (the space inside is loosely egg shaped). Again we see the taper at the top, and the opening at the bottom. All ribs radiate from the spinal column and MOST attach at the sternum, some being short arcs others being long loping arcs. It is important to note that these ribs are not cylindrical curves, but thick flat curves, and in most cases with flex joints (look just to the left and right of the sternum to see a plane shift at that junction.)


Below is the Dorsal View of the Cage. Here we see the spinal column and ribs reaching around to the front. Again we see a plane shift on these flat rib shapes- they are not round rings, but a segmented arc (think about breathing and how important it is for some flex to happen.)
In this and the last example note how the artist presented the sense of volume inside the cage, through the ribs we see the continuation of each rib but it recedes through value shift and line (possibly atmospheric perspective!)


Below we see the Dorsal trunk (back) focusing of the shoulder girdle. Note the shape and form of the scapula, where it lies on the cage, the angle at which it rises to meet the clavicle on the front.

Below is an example of the Pelvis take from The Human Figure, Jon H. Vanderpoel. Here we see a good description of contour line as it relates to the undulating form of the pelvis. Notice the butterfly shape of the structure and the hollows within. Important landmarks are the ilium crest (upper most point of the pelvis, the semicircular shapes) and the Ischium (rings at the bottom) and the Sacrum (on the backside the area around the Coccyx)

Here is an example of the Spinal Column (Human Anatomy for Artists) illustrating the three views and most importantly the gentle S- like curve. Notice the shapes of the vertebrae, cylindrical in front and wing protrusions in the back. Also observe the relative size of the vertebrae big to small top to bottom.
Another Example from John Vanderpoel illustrating the angles of these forms with the body. Note how and where they open and constrict on opposite sides.


Sunday, October 17, 2010

BASIC PERSPECTIVE


Perspective- a technique of depicting volumes and spatial relationships on a flat surface.

Linear Perspective - a mathematical system for representing three-dimensional objects and space on a two-dimensional surface by means of intersecting lines that are drawn vertically and horizontally and that radiate from one point(one-point perspective),two points (two-point perspective), or several points on a horizon line as perceived by a viewer imagined in an arbitrarily fixed position.

Atmospheric Perspective (or Aerial Perspective)- a technique of rendering depth or distance in painting or drawing by modifying the tone or hue and distinctness of objects perceived as receding from the picture plane, esp. by reducing distinctive local colors and contrasts of light and dark to a uniform light bluish-gray color.

Picture Plane- An imaginary "pane of glass" at which the viewers gaze meets the illusion created on the two dimensional surface. To extend the analogy, the viewer would trace on this glass the three- dimensional object. Not just the material surface, a concept.

Horizon Line- A level horizontal line located at eye level.

Vanishing Point- A point of convergence of parallel lines located on the Horizon Line.

Scale- The apparent size of an object.



This example illustrates the same object in relationship to the Horizon Line (Above and Below.) Notice whether you can see the top of the cube or the bottom, which way the diagonal lines slope to the vanishing point.

The following Four examples were taken from Basic Perspective Drawing- John Montague.





This example illustrates the top of a cylinder (circle) as it approaches the Horizon Line. Notice how it changes to an elipse and further squeezes to a line.


Piranesi- Prision Series

Rackstraw Downes

Al Held
Student Example

Student Example

Wednesday, October 13, 2010

Paraline Drawing Project

Plan and a Plan Oblique of a Cube:

1. Begin by drawing the top view of the cube. This is a 4" square. This will serve as your Plan.

2. Begin the Plan Oblique by drawing a second square on its corner. With a triangle ruler set the square on a 45 degree angle, be sure to keep the measurements accurate. When finished it will look like a diamond.

3. With ruler, draw vertical, parallel lines from all corners that measure 4" up.

4. From the end point of the vertical left line use the Triangle Ruler to find a 45 degree angle and project it to the end point of the next line segment. Continue to connect line segments at 45 degree angles until the form is complete.

5. The Cube now appears transparent. Erase interior lines so the cube appears opaque.


Oblique drawings from Plan and Elevation:

Plan




Elevation



Result







Analysis and Convention- Paraline & Orthographic Drawing

Paraline- 3-dimensional drawings where parallel lines remain parallel - Isometric and Oblique

Oblique - Adjective (drafting) -designating a method of projection(oblique projection) in which a three-dimensional object is represented by a drawing (oblique drawing) in which the face, usually parallel to the picture plane, is represented in accurate or exact proportion, and all other faces are shown at any convenient angle other than 90°.

Plan- A view from above.

Elevation- A view of the from the front, back or side.

The following examples are taken from the Basic Perspective Drawing- A Visual Approach by John Montague.