A sketch is a quick freehand drawing, used to capture a fleeting image or reproduce an idea in a brief non-detailed manner. Artists often produce a number of such sketches, before they finally settle on one that they convert to a complete painting. Sketching is then, a sort of artistic brainstorming. The major difference between a sketch and a drawing is the speed with which the former is executed.
Types of Sketchings
There are several mediums that are used for the purpose of sketching. The Renaissance artists made sketches using a silver stylus on specially prepared paper.
Today, sketching is done using graphite pencils, pen and ink, charcoal, crayon, color pencils, inked brushes, pastels and markers.
The graphite pencil comes in various thicknesses and degrees of softness of the graphite. This makes them highly versatile, as they can be used for outlining, shading, filling etc. In the pencil erasing method, the lines that are created are smudged to achieve fullness and various shades. An art gum eraser or hard eraser is generally used. While the former does not completely erase the graphite mark, the latter does.
In the pen and ink technique , the sketch is made using colored ink that is applied via a pen or other stylus. The crow-quill dip pen is used to produce fine lines, while pens with broader nibs produce thicker lines. For technical drawing, the Rotring Rapidograph or Isograph pens are used. Comic book and graphic novel artists prefer using the micron pen. Artists also favour the waterproof Indian ink to the formerly used Iron-gall nut ink, which was a purple-black ink made from tannin and iron salts.
Crayons made of wax, charcoal or chalk are also used for sketching. A crayon made of oiled chalk is called an oil pastel. When it is made of pigment with a dry binder, it is simply a pastel.
Often, artists use markers or marker pens . These are pens which have a tip made of a porous material. A felt-tipped pen is a marker pen with a felt tip.
Techniques of Sketching
There are several techniques that are employed to make sketches more attractive and detailed. These include hatching, crosshatching, random hatching, scribbling, stippling, blending, circular shading and angular build-up.
Hatching is the method used to play with the brightness of an image. It is the sketching of closely spaced parallel lines. This is done by varying the thickness, spacing and number of lines. A number of thick closely spaced lines produce a darker image. When lines are placed at an angle to each other, it is called cross-hatching . This method is used to create contrast. Different colors may be indicated by using different line-work.
The technique of stippling involves using small dots, to indicate shading and solidity. The denser the dots, the darker the shade.
Uses of Sketching
The art of sketching is not simply restricted to the creative artist to give shape to his imagination, and aid him in his work. It is also employed for practical purposes.
Courtroom artists are usually sketchers.
Forensic sketches are used to identify wanted people.
Street sketchers earn quick money by making portraits of tourists.
The famous sketches of Leonardo da Vinci , are a delight to behold.