(see value also)
bc3onions4bit.gifBlind Contour

3onions4bit.gifModified Contour with the addition of some contour lines

cont49.jpg Contour lines. notice how they define the form of the object ataking it from flat shape to form. notice also the aspect of light causing the illusion of depth along with the contour lines.
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Gesture drawing also defines form as well as movement

The quality of line is very important in drawing

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simply put good line quality defines good drawing from bad drawing.

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if you study above, then you will understand how artists such as Van Gogh used shading to define his illusions of space and depth.

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Van Gogh used light , dark, short, long, you name it with regards to line quality and or characteristics.
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degas' drawing of hands exhibits great line quality.
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Below light and shadow.
Light and shadow give shape a form. this is part of the illusion of depth.
Shadow is the absence of light.
Shading is the act of making shadow.

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Rays of light determine the shadows length, the angle actually of the light rays hitting the object.


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The parts of a shadow and shading. there is also rim light which some refer to as reflected light but it is actually a pictorial device that separated an object from the darkness of the shadow. It is a thin strip of light on the object between the dark of the object and the dark of the shadow. Is it real? i do not know but it works so well that i tend to see it there, real or not.

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different degrees of pencil. graphite is made from graphite and clay. the more clay the lighter the graphite.
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above is a value scale.
it is a way of measuring light.

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Shading techniques for sketching or drawing. Smudging is also called blending.
hatching is defined as a 45degree parallel mark. our eyes flatten out horizontal and vertical marks even though they can be used in heaven dark shading.
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Albrect Durer
was a master draftsman. look at his use of cross hatching and contour hatching here.