Depending on how you define them, there’s any number of different elements to consider when composing an image, but one way the key components can be broken down is into line, shape, colour texture, form, value and space.
Line is an illusion created by the edges of objects. Many drawings styles use lines to define the boundaries of objects within an image, as even though lines don’t actually exist it’s the easiest way to convey form. Whether the lines within an composition are actual lines or merely the edges of contrasting tones or hues, they’ll be one of the most easily identifiable features.
Shape is self-explanatory, and refers to both individual objects and combined objects. Colour is deceptively difficult to use properly, it does little to define objects, rather creates mood, warmth or cool. It can be used to bring attention to certain areas of an image, but not as well as tonal value.
Tonal value describes how light or dark a part of an image is. Tonal value is arguably the most important part of an image, since it’s the most visible part. Form describes the 3-dimensional qualities of an element, which is expressed through shading and perspective.
Texture is similar to form in that it can describe 3-dimentional qualities within an image, except instead of describing the overall structure it describes the tactile qualities. Texture is the difference between a reflective surface and a matte surface or a smooth surface and a grainy surface. Mostly texture adds detail and realism to an image.
Space is the proportion of an image that objects occupy; conversely, negative space is the portion of the image surrounding them or between them. Usually the focus of an image with be the positive space – the object or person the picture is focusing on – but sometimes the negative space can be the subject, for instance if the image is focusing on a piece of sky between trees or buildings.
So, how do these all work within an image?
There are eight elements of composition to consider: unity, balance, movement, rhythm, focus contrast, pattern and proportion.
There are established principles for composition; some things work and some things just look ‘wrong’. The easiest principle to follow is the rule of thirds. Elements within an image will look best placed a third of the way up an image, or a third of the way along. By dividing an image into nine equal sections, you can identify the four focal points.
Focal points are places in an image where you intend the viewer to spend the most time looking. There are certain things people’s eyes will naturally gravitate towards, such as faces and hands. More detailed areas will also draw more attention, as will bright colours and contrasting hues.
If there is more than one focal point, they need to be arranged so that they are balanced. To some extent, symmetry in an image makes the composition feel grounded, but can also make it look unnatural.
Asymmetrical balance, which uses elements which are equal, but different, looks much more natural.