This page contains some basic terminology that may hopefully help with reading other pages in the Photography 101 section here. 

Angle of view - The portion of a scene that is seen by the camera lens. The width and proportion of the scene is determined by the focal length of the lens. A wide angle (short focal length) includes more of a scene, or a wider view, than a normal (normal focal length) or telephoto (longer focal length) lens.

Aperture  - The lens opening. This controls the amount of light that passes through the lens. The size of the aperture is adjustable with rare exception of a few lenses. Lens openings are referred to as f-numbers or f-stops.

Balance  - The placement of colors, light and dark areas, or large or small objects in a photograph to create harmony or equilibrium.

Burning  - Purposely giving one or more areas of the photograph more exposure in printing or post processing to darken the particular area.

Composition  - The arrangement of all of the elements of a photograph; main subject, foreground, background, and supporting subjects.

Contact  - The process by which a piece of film is placed upon another piece of unexposed film or photographic paper and subjected to light in order to reverse the image in a 1:1 ratio.

Contrast -  The density range of a negative, print, slide, or digital image; the brightness range of a subject or the scene lighting.

Density  - The blackness of an area of a negative, print or digital image that determines how much light will pass through or reflect from it.

Depth of Field (Depth of Focus) - The distance range between the nearest and farthest objects that appear in acceptably sharp focus in a photograph. For all practical purposes, it depends on the lens opening, focal length of the lens, and the distance of the lens from the subject.

Developer  - A solution used to turn the latent image into a visible image on exposed film and photographic papers.

Diaphragm  - The lens opening. A perforated plate or adjustable opening mounted between or behind the elements of a lens which is used to control the amount of light the reached the film, paper, or sensor. These opening are usually referred to as f-numbers.

Dodging  - Purposely giving one or more areas of the photograph less exposure in printing or post processing to lighten the particular area.

Emulsion     - A thin coating of light sensitive material, usually a silver halide gelatin, in which the image is formed in film and photographic papers.

Exposure  - The quantity of light allowed to act on a photographic medium. Exposure is a product of, intensity (controlled by the lens opening), duration (controlled by the shutter speed or enlarging time), and the ISO (ASA) which is the sensitivity of the photographic medium to light.

Exposure Meter  - An instrument with a light sensitive cell that measures the light reflected from or falling on a subject. They are used as an aid to select the exposure setting. Synonymous to a light meter.

Film Speed  - The sensitivity of a given film to light, indicated by a number. The higher the number, the more sensitive (faster) the film. ISO settings on digital cameras are the equivalent to film speed.

Filter  - A piece of glass or other transparent material used to cover the lens to emphasize, eliminate, or change the color or density of the entire scene or certain elements of a scene.

Flashing  - Giving the edges of the paper more light in order to darken them. Same as a dark vignette in post processing digital images.

Flat Lighting  - Lighting the produces very little contrast or modeling on the subject and gives minimum shadows.

Focus  - The adjustment of the distance setting on the lens so the subject is sharply defined.

Graininess  - The sandlike or granular appearance of a negative, print, slide, or digital image. With print and film it results from the clumping of silver grains during the development of film. Graininess become more pronounced with faster films, increased density in the negative, and the degree of enlargement. With digital imaging, noise is the visual manifestation of a lower signal-to-noise ratio, which is measured in decibels.

High Contrast  - A wide range of of density in a print or negative.

Highlights  - The brightness areas of a subject and the corresponding areas in the negative, print, slide, or digital image.

Latent Image  - The invisible image left by the action of light on a photographic film or paper. The light changes the photosensitive salts to varying degrees depending on the amount of light striking them. When processed, the latent image will become a visible image either in reversed tones (as in a negative) or in positive tones (as in a print or transparency). 

Lens  - One or more pieces of optical glass or similar material designed to collect and focus rays of light to form a sharp image on film, paper, projection screen, or digital sensor.

Lighting  - The illumination falling on a subject, particularly in the direction or arrangement of the illumination.

Negative  - The developed film that contains the reversed image of the original scene.

Normal Lens  - A lens that makes the image in a photograph in a perspective similar to that of the original scene. A normal lens has a shorter focal length and a wider field of view than a telephoto lens and a narrower field of view than a wide angle lens.

Orthochromatic Film  - Black and white film that is sensitive to all colors of light except the red spectrum.

Panchomatic Film  - Sensitization of a black and white film so that it records in tones of about the relative brightness as the human eye sees in the original scene.

Positive  - The opposite of a negative; an image with the same tonal relationships as those of the original scene - for example, a finished print or slide. Negative films can be used to make positive images by contacting the negative with an unexposed piece of negative film.

Prime Lens  - A lens with a single focal length that can not be changed.

Print  - A positive picture, usually on paper, and usually produced from a negative or slide.

Shutter  - Blades, a curtain, a plate, or other moveable cover in a camera or lens which controls the time during which light reaches the film or digital sensor.

Slide  - A photographic transparency, usually color, that is mounted for projection.

Stock Solution  - A chemical solution which requires further dilution to work with. Stock solutions most always have a longer shelf life than a working solution.

Telephoto Lens  - A lens that makes a subject appear larger on film than does a normal lens at the same camera-to-subject distance. A telephoto lens has a longer focal length and a narrower field of view than a normal lens.

Vignetting  - Printing the central area of a picture while shading the edge areas into white. Also, the cutting off of the edges of the frame by filters or other lens attachment, especially when they are stacked. This happens much more commonly on wide angle lenses.

Wide Angle Lens  - A lens that has a shorter focal length and a wider field of view (includes more subject area) than a normal lens.

Working Solution  - A chemical solution that is used in the development of negatives or the printing of pictures. It is the most diluted substance that you work with.

Zoom Lens  - A lens in which the focal length can be adjusted over a wide range, giving the photographer, in effect, lenses of many focal lengths.