Basic Concepts of Photography

Lighting and Exposure
How the lighting of a scene affects the exposure of the film is one of the most basic photography concepts. The more light within the scene, the more the film will be exposed.

Conversely, the less light a scene has, the less the film will be exposed. While over-exposed film turns out pictures that are too bright, under-exposed film will be too dark, appearing “blacked-out.” Understanding how to manipulate lighting will help a photographer properly expose his film.
Have you ever seen or taken pictures that are so light or so dark that one can hardly make out the subjects? That shows the importance the proper lighting and exposure in photography.

In any given scene a subject can be fully lit with direct light, fully lit with indirect light or partially lit with backlighting or ambient lighting. Any directly lit subject is relatively easy to photograph, meaning that the film will be properly exposed and the picture will “turn out.” On the other hand, partially lit subjects are a bit more elusive: generally, the lighting or film speed should be manipulated to ensure the adequate level of exposure.

Learning how to alter the film speeds and lighting in poorly lit scenes takes some effort. However, a photographer can purchase a light meter, a tool that measures the amount of light in a scene. Given this measurement, the photographer can choose the appropriate film speed.

Composition and Camera Angles
Composition, or the technique of setting up the subject within the camera’s frame, is another basic principle of photography. The proper composition of a shot is directly related to the angle at which the photographer takes the picture. With a particular camera angle and a planned composition, a photo can draw in the viewer’s eye, add meaning to the image or add a sense of movement and dynamism to the scene.

By drawing the viewer’s eye to a particular part of a picture, the photographer also invests a particular meaning of feeling to his shot. Depending on the subject photographed, its placement within the frame can make it appear more mysterious, forceful, compliant, or intriguing.

If a photographer wishes his viewer to focus on a certain aspect of the shot, he can place the subject in a certain area of the frame. For example, putting the subject higher in the frame gives the subject an imposing presence on the viewer. On the other hand, placing the image lower tends to make the subject more submissive and possibly more mysterious to the critical viewer’s eye.

Another set of basic photography concepts involves the skills used by a photographer to make an image appear dynamic. For instance, a shot with the subject framed directly in the middle can make the viewer feel as though he is falling into the subject.

An example of this would be a picture of a person looking through a hollow log while the photographer is at the other end of the log snapping a picture of the person’s face. In this shot, the viewer’s vision moves through this tunnel, shooting immediately towards the person’s face. While not as overtly dynamic as action shots, this sort of compositional concept adds a subtle sense of movement to the picture.

Aberration
Aberration, also known as “color fringing,” refers to the effect in which light passing through a lens becomes blurred and produces a fuzzy image on the film. If the camera lens is unable to focus light of different wavelengths or if the lens is scratched or otherwise damaged, chromatic aberration of the final image will occur.

In a normal lens where aberration doesn’t occur, the lens directs light of different wavelengths to specific areas of the film, depending on the particular wavelength. This process results in a balanced, clear and sharp image on the resulting photo. However, when this process doesn’t occur, aberration distorts the color and clarity of the original image, ruining the resulting pictures. Often, the edges of the pictures are the most distorted areas.

Aberration can occur in six different ways:
· Astigmatism aberration
· Chromatic aberration
· Coma aberration
· Curvature of field aberration
· Distortion aberration
· Spherical aberration.

Although some photographers generally consider aberration to be a negative photographic effect, others have used it to artistic effect. By intentionally blurring parts of a photo, the photographer can effectively comment on the distorted features or nature of the subject that he is photographing.

Angle of View
Angle of View is the amount of a scene a photograph captures and can be measured vertically, horizontally or diagonally. Also known as angle of coverage or field of view, angle of view changes given the type of lens a photographer uses to take a picture.

While wide-angle lens tend to capture more of a scene than any other lenses, longer lenses generally get about two degrees of a scene within their angle of view.

The further away an image that a photographer is attempting to capture within their angle of view, the longer and more narrow the lens should be. For instance, a picture of the stars or far-off marine life would be taken with a longer, narrower lens than one that has an image with an angle of view that is twenty feet away. Similarly, if a photographer wants to include more or less light within an angle of view, they can use a petal or a hooded lens respectively.

Whether you are a novice or expert photographer, changing the angle of view of a scene can add a fresh, unique spin to a traditional picture. Rather than shooting a photo straight on, as is the traditional method, a lowered or slanted angle of view may give your pictures an unconventional flare.

Aperture
Aperture refers to the lens diaphragm on a camera that controls the amount of light that touches the film when the shutter opens. Settings for an aperture opening are measured in f-numbers, also known as the F-Stop. F-numbers are calculated by dividing the length of the lens’ diameter by the focal length. Aperture settings are generally located or adjusted on the outer edge of a camera’s lens.

Larger aperture settings, ranging from around f3.0 to f5.5, allow more light to enter through the lens. Consequently, if a photographer sets his aperture to a higher number, a single object will become the photo’s central feature, significantly minimizing any figures in the pictures background. Larger apertures are commonly used for portraits or close-ups.
Alternatively, smaller apertures, ranging from f16 to f32, include more figures in the foreground, as well as the background. In such pictures, more elements are clearly defined than a single central object. As a result, photos taken with narrower apertures lend more perspective to a scene. Landscapes and cityscapes are the usual subjects of pictures taken with smaller apertures.

If a photographer is taking a picture that doesn’t require an extreme close-up nor a broad scope, an aperture setting from f8 to about f11 tends to yield well-defined images.

Aspect Ratio
Aspect Ratio is a measurement of a photograph’s width to height. Commonly, 35 mm film measures 36:24, creating an aspect ration of 3:2. Such an aspect ratio tends to produce 6″x4″ printed pictures. Although aspect ratios are a central descriptor in photography, they are also important in cinema and computer technology.

Aspect ratios for different mediums have specifically lettered prefixes to distinguish them. “H” represents the prefix for HDTV aspect ratios; “C” stands for standard, or ‘classic’, aspect ratios; “P” indicates panoramic aspect ratios. While “H” is the prefix used for television, both “C” and “P” can be used for photographic aspect ratios.

It is important to know a film’s aspect ratio because varying ratios may not conform clearly to certain photo print sizes. Therefore, if you want to print a photograph at a specific size, you should examine an aspect ratio chart to assess what aspect ratio for film that you will need so that the image shows up clearly.

If you attempt to print photographs that don’t conform to the film’s aspect ratio, the photo printer will either pad the picture’s edges (i.e. by adding a border) or crop the photo’s top and/or sides. By altering the shape of the print, the photo printer can maintain the integrity of the image.

Auto-focus
Auto-focus refers to a camera’s ability to automatically adjust and focus its lens on a framed image. It functions by using a number of focus points to zero in on the object; then, small motors automatically position the lens into proper focus. The number of focus points a camera is capable of generally increases the more expensive the camera is.

Cameras can come equipped with one of two types of auto-focus systems: a passive auto-focus or an active auto-focus. While the passive mechanism uses sensors to detect contrasting light, active auto-focus uses timed lasers to calculate the image’s distance and then adjust the lens accordingly.

Nearly all digital cameras today are equipped with an auto-focus and a manual focus mode.

Although Pentax ME-F first developed auto-focus in 1981, it didn’t become a standard feature on consumer cameras until 1985. However, not all consumer camera manufacturers embraced the auto-focus mechanism. While Cannon and Minolta immediately made auto-focus a feature of their camera, Nikon and Pentax resisted. To this day, both Nikon and Pentax continue to produce manual cameras.

Pictures taken with a camera on auto-focus, however, can lack some of the features associated with manual camera photos. Experts tend to agree that photographs taken with auto-focus have poorer definition and lack continuous color in their depths of field. Similarly, cameras with auto-focus generally have less aperture settings. Consequently, auto-focus can limit the degree to which a photographer can manipulate his pictures.

More Advanced Photography Concepts
If a photographer wish to further expand your knowledge of photography concepts, he should start experimenting with some more advanced techniques, such as:
· aperture settings
· depth of field measurements
· focal lengths
· shutter speed settings.