"At a distance the oak seems to be of ordinary size. But if I place myself under its branches, the impression changes completely: I see it as big, and even terrifying in its bigness." - Eugene DelacroixThis quote by a fellow artist sums up the idea that perspective matters. The oak can either look small and insignificant or it can astonish you with it's height and width.
In your painting you will want to note this fact before you begin to paint. Color speaks, but not as loudly without perspective.
When you place your composition you probably place it into one of these four main categories already:
1) Linear perspective
2) Size and Vertical Location
3) Detail (Aerial or Atmospheric Perspective,) or,
I am teaching these perspectives to you so that you will better understand how each of these perspectives are different and how to decide which of these perspectives will go best with the desired mood or the characteristics that you wish to convey to your audience. The first perspective that we will be going over is linear perspective.
1) Linear Perspective
Linear perspective is based on the idea that all lines will converge on a common point on the horizon called the vanishing point. You have observed linear perspective when you notice that the lines on the highway appear to meet at a point in the distance. Artists use linear perspective to create a focal point for a picture. Any walls, ceilings, floors or other objects with lines will appear to come together at the horizon line. These lines converging lead our eyes towards that point. Often, the most important object or person in the picture will be located at that point. Linear perspective is a very focusing perspective and will use lines to create the focus.
2.) Size and Vertical Location
Since objects in our environment look smaller when they are farther away, the easiest way to show depth is to vary the size of objects with closer objects being larger and more distant objects being smaller. We also perceive objects that are higher on the page and smaller as being further away than objects which are in the forefront of a picture. This perspective is often used for landscapes because of it's simplicity and realistic view of nature.
3.) Detail (Aerial or Atmospheric Perspective.)
The atmospheric perspective uses color and value contrasts to show depth. Objects which are further away generally have less distinct contrast - they may fade into the background or become indistinct dark areas. However, while the background values are indistinct, the foreground objects will be clear with sharper contrast. This perspective is used most often by impressionists. Though realists artists will use it at times, the impressionists will use this perspective to it's highest value. They will contrast their subject, and dim the rest of the painting softly into a very non-focused background.
When objects are partially obscured by other objects in front of them, we perceive them as further back then the covering objects. We do not see them as incomplete forms, just further back. Most artists will use this method when they are painting a pantry or mountains. It is a perspective method on detailing distance.
I hope that this lesson has taught you some of the basics on perspective. If you wish to view more information on this subject you can find more here:
The Linear Perspective
A Painting Book (See chapter 16 for the perspectives)
Detail (Aerial or Atmospheric Perspective)
The Overlapping Perspective