Return to the Perspective Menu |
|
As artists we have to make decisions on a regular basis. We have to decide specifics for those who encounter our works. Each decision builds a foundation for the next one. Eventually so many decisions have been made that a viable work of art is produced. To not decide is to flounder, procrastinate, or become nonproductive. To decide is to produce, and to create. Creativity then might be considered the end result of a long string of decisions. Once you have made them all and followed them through, you have accomplished a creative act which we will here call art.
The subject before us is Linear Perspective, and the concept we will deal with is our first set of important decisions. From what point in space is this picture seen? Like a camera image, painted and drawn pictures are ultimately flat and they appear to be on a flat surface. Our minds may reconstruct the perceived foreshortened shapes into mentally recognizable constructs, but ultimately they are flat shapes on a flat surface. Each image is drawn or photographed to be seen correctly from one point in space. Any other angle produces a flattened (even if it is still understandable) image.
For a camera, this point is simple to reconstruct. It is where the camera itself was positioned when the picture was taken. Telephoto lenses can zoom in and enlarge specific parts of the image, but ultimately this point never actually moves. We refer to this point as the station point.
When drawing a picture, we have to make some tough decisions right off. Since there is no camera involved, we have to decide on our own station point. This decision will influence the rest of the image, but it is not necessarily a difficult one when we understand the different angles involved.
Spike has agreed to help us illustrate the most basic angles for a linear perspective drawing. If you ever see a diagram of a rendering that has any of the above abbreviations on it, you can be sure that someone has taken the time to use at least some of these concepts.
Center Line [of Vision] (abbreviated CL or CLV): This imaginary line represents the center of the viewers field of vision. This line is perpendicular (90 degrees) to the Horizon Line.
Center of Vision (abbreviated CV): This point represents the place where the Horizon Line intersects the Picture Plane.
Horizon Line (abbreviated HL): This represents the eye level of the viewer. It is not always necessary to draw this into your pictures, but it helps to establish one at the beginning in order to arrange the rest of the composition around it.
Cone of Vision: This is a circular area about 60 degrees wide (30 degrees above, below, and to each side of the Center of Vision. Some sources will place it as far as 90 degrees across, while others will constrain it closer to 45 degrees. The farther your perspective drawing travels away from the Center of Vision, the more warpage that may be detected by onlookers.
Picture Plane (abbreviated PP): This is a theoretical flat surface on which you draw. It is parallel to the Horizon Line and perpendicular to the Center Line. You do not need to draw on this surface while standing at the the Station Point. You can move closer or farther away, while remembering where everything goes.
Station Point (abbreviated SP): This is the place where the perspective drawing is best seen from. In a photograph, it would be the actual place where the camera was when the picture was taken. In our above diagram it is where Spike's eyes are.
The last basic concept to define is the Vanishing Point (abbreviated VP). Vanishing Points are usually located on the Horizon Line and represent the place where objects would diminish in size (remember diminution and convergence?) to the point that they can no longer be seen because they are so far away that they appear too small.
There are other concepts to juggle when working in linear perspective, but these should get us started just fine. Most of the others can be ignored until we need them later, since they are just reorganizations and practical applications of the ideas outlined above. Our next step is to deal with the basic decision making process for a linear perspective composition.