Every representational painting (that is to say, a painting that represents something specific, rather than a purely abstract painting) has a subject or several subjects. Some paintings have a simple composition with one easily defined subject, such as Leonardo da Vinci's portrait of the Mona Lisa, but many other paintings have several characters or objects, and, in general, just a lot of stuff going on. There may be a great deal to look at in a busy picture, but to capture the eye of the viewer, a painting must have a well-defined focal point. Once the eye is arrested by this focal point, the viewer will stay to take in the rest of your artwork.
To determine your focal point, decide what or who should be the star of the show. Pictures of the Assumption, for example, generally put the spotlight on Mary, but you might consider putting the focus on a watching child, to show that the event is being seen from her perspective.
Once you have selected your focal point, you can go about emphasizing it with one or more of the following techniques:
Framing Device. Set off your subject by placing it within a picture element that serves as a natural frame: a doorway or archway, a window, an arching tree branch or spray of flowers, a bonnet or helmet around a face. You can even use an actual frame, such as a mirror's reflection or someone standing in front of a framed picture.
Movement. In Leonardo da Vinci's painting The Last Supper, perspective is used to guide the eye toward the focal point. The lines of the walls and ceiling diminish toward the vanishing point, which happens to be face of Jesus Christ. In addition to the basic movement, Leonardo also has some of the disciples literally pointing at or reaching toward Jesus, which naturally leads the eye back again and again. Leonardo also uses a framing device, in that Jesus is seated in front of a window in the center of the painting.
Color. An effective way to attract attention to your focal point is the use of color. If your painting is full of blues and greens, as is a typical landscape, a red barn or bright yellow sunflower will provide an eye-catching burst of contrasting color (although be aware that a red barn is an extremely cliché subject). The color doesn't have to be bright, though, just different: In Vincent van Gogh's painting, Les Irises, a lone white iris stands out from its colorful bluish-purple peers and the reddish-orange ground because it is so singular.
Contrast. Along the same lines, contrast can be employed to pick out your main subject, as well. Putting something light in a dark area or something dark in a light area will draw the eye like a target. Most creatures, including people, are instinctively drawn to eyes (and Nature exploits this fact by equipping some animals with an "eye spot" pattern that can help them escape or intimidate predators), because there is such contrast in an eye (even fingernails and teeth are not as naturally white as an eyeball, nor is anything on the body as black as a pupil). In The Oath of the Horatii, Jacques-Louis David's picture of Roman soldiers swearing fealty to their captain upon their swords, the swords are shown shining brightly against a dark background. They are further framed by an archway, and if that weren't enough to establish them as the focal point, movement is also used, as both the captain and the group of soldiers stretch their arms out toward the swords as the oath is sworn.
Definition. The relative amount of definition, or detail, can be used to home in on a focal point, much like one's eye focuses naturally on a subject of interest and lets the other stuff blur out a bit. In Portrait of a Madwoman, GĂ©ricault renders the face of his subject with incredible sensitivity to detail, showing the rough, age-spotted skin of her face, her red-rimmed eyes and querulous expression perfectly. Her white cap (a framing device) is shown in slightly lesser detail, and the farther one travels from her face, the less focus there is: Her brown mantle is barely indicated in loose brushstrokes, and the background is featureless black.
Size. Just as with a contrast in color or level of detail, a dramatic difference in size can draw the eye to a focal point. A watermelon among oranges would certainly stand out, but a focal point doesn't have to be the picture's largest item, just the most singularly different in size. An orange among watermelons would command attention just as effectively.
Finally, there is Placement. There is always a "sweet spot" on a typical rectangular page or canvas to which the gaze normally gravitates. On both "landscape" (horizontal) and "portrait" (vertical) orientations, that spot is about one third down the center of the page. The hilts of the swords and the captain's raised hand are in the "sweet spot" in The Oath of the Horatii, above. The portraits of the Mona Lisa and the madwoman, above, have the faces located there. Armed with the knowledge that people will naturally tend to look in that area first, you can plan your composition to put the focal point there. But do not feel locked in to that particular spot; with the use of contrast, framing, movement, or the other techniques I've discussed here, you can direct the eye to your preferred location, and very often an "off-center" focal point makes for a more dynamic composition.
Whatever methods you choose to enhance your painting, always be open to experimentation, and keep making art!
Want more art instruction? Check out the following articles:
http://allsortsartbyali.blogspot.com/2015/05/figure-drawing-101-so-you-wanna-be.html
http://allsortsartbyali.blogspot.com/2015/03/figure-drawing-101-wacky-secrets-of.html
http://allsortsartbyali.blogspot.com/2015/03/i-have-been-professional-portrait.html
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