Knutsford Photographic Society

Jargon Corner

Here is a glossary of common photographic terms you may heard. If you would like to contribute any further glossary definitions for inclusion here, please e-mail them to : webmaster@knutsofrdps.org.uk . We hope you find it helpful.

Jargon Corner

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

Acetic Acid

In the darkroom, a chemical used in stop baths to neutralise and stop development before prints of negatives are put in the fixer i.e. it stops the picture developing further once the correct tonal and contrast balances have been achieved.

Agitation

In the darkroom, this is the technique of constantly moves the print or negative so that fresh chemicals are kept in contact with the emulsion surface.

Air brushing

An advanced technique of retouching used on prints. It involves a fine high-pressure spray of ink. Some photo-editing software offers an equivalent facility for manipulating digital images.

Aperture

The opening of the lens, where the light comes in to expose the film. Most cameras control the aperture automatically to bring the correct amount of light through the lens onto the film; on many this can also be overridden. The lens setting which denotes aperture is called F-stop e.g. f2.8, f11 etc. With manual controls, the aperture can be stopped down/up by altering the f-stop from the camera-suggested setting, which lets in less/more light. Here the shutter speed needs to be altered correspondingly to retain a correct exposure.

Some cameras have a manual override to allow for varying effects resulting by altering the amount of light admitted for above/below correct exposure. Where aperture can be manually overridden, opening the aperture by one stop doubles the amount of light reaching the film. See also Auto Bracketing and Bracketing.

Aperture-priority

A facility on the camera by which the photographer sets the aperture (‘f’ number) and the camera automatically sets the shutter speed for a correct exposure.

APS Advanced Photo System

This film type and camera format was introduced in the 1990s. For popularist use it combines easy film loading with easy use. There are 3 print sizes and an index is provided instead of negatives.

APS includes the PQI (Print Quality Improvement) feature. This reads information about the shot and records it on the film’s magnetic layer, thus allowing a more accurate end result.

ASA

See ISO

Auto Bracketing

A system which allows a camera to take a series of photographs, each at a different exposure. From the photographs produced the photographer can select the one which appears to have the most accurate or desired exposure. See also Bracketing.

Auto Exposure

Uses a built in light meter in the camera to calculate the correct exposure (i.e. aperture and shutter speed) for a given situation.

Auto Focus

A system by which the camera correctly focuses the camera lens for a given subject/scene.

B

Backlight Compensation

A useful feature when your subject is standing in front of a very brightly lit area. In that case a camera’s auto exposure will usually expose for the bright background, causing the subject to be a silhouette. Backlight compensation adjusts the camera to correctly expose for the subject (NB in this case the background may become even brighter on the finished result!)

Back Projection

In the studio, this technique allows the photographer to artificially recreate a desired background for a shot, with the subject (e.g. a model) placed in the studio in front of the artificial backdrop. Also used as an alternative means of projection to replace the traditional projection via a slide projector onto the front of a screen.

Back projection works by projecting the required background/image onto a translucent screen. Often also used for presentations to large conferences.

Bellows

A lightproof folding sleeve placed between the lens and camera, mainly used for close-up work.

Bleaching

Used in the darkroom, this chemical process converts the black silver image into a colourless image. It’s the first step sepia toning.

Blur

No, not a 1990s pop group, but the fuzziness that occurs from camera shake, when a camera is not held firmly or when the exposure is too long for a camera to be ‘hand held’.

Bracketing

As for auto bracketing but done manually. Usually the photographer will take the series in half or one spot increments above and/or below the exposure recommended automatically by the camera.

Bromide Paper

A light-sensitive paper for printing photographs.

Bulb Setting

Usually depicted as ‘B’ on the shutter speed selector on the camera, this allows the shutter to be kept open as long as the shutter release is pressed. To avoid camera shake use a tripod and a cable release/infrared release/time delay to activate the shutter. See also Cable Release.

Bulk Film

The purchase of large single quantities of film which makes the overall cost of the film cheaper. Sometimes camera club members group together to buy film in bulk.

Burning-In

In the darkroom this technique is used to control the development of small areas during development. The addition of small beams of light (usually from the enlarger) controlled through use of the fingers or a purpose-built dodger (usually a lolly-shaped tool, homemade out of paper and wire), which enables the bringing in of more/less exposure during development. Some photo-editing software offers an equivalent facility for manipulating digital images.

C

Cable Release

A cable which attaches to the camera and also the shutter and allows the shutter to be opened from a distance without having to touch the camera, thus avoiding camera shake.

Camera Shake

See Blur and Hand Held

Coated Lens

A lens with a coated surface used to reduce flare.

D

Depth of Field

The area in front of and behind the actual point of focus which is additionally in focus. A small aperture results in a greater depth of field, a larger aperture a smaller depth of field.

Depth of Field Preview

A facility of the camera which allows the photographer to see the depth of field effect which the currently selected aperture will produce.

DIN

See ISO

Drying Marks

Blotches found on a print or negative resulting from insufficient washing in the darkroom or automated film processing.

DX Coding

Allows certain cameras to automatically detect the film speed for a given roll of film. If you look at the canister of a roll of 35mm or APS film, if it is marked as DX and if your camera has a DX facility, then the camera will automatically select the speed of the film on your camera.

E

Extension Tube

One or more rings which are placed between the camera body and its lens resulting in an image being magnified. Also useful for improved focusing on close-up objects.

Exposure Meter

Built into many cameras, they measure the amount of light entering the camera.

Eyesight Correction

Adjusts the camera to cater for variations in individuals’ eyesight (applies to focusing primarily)

Exposure

See Aperture

F

Fast

See Film Speed

Film Format

Refers to the dimensions that apply to the film to be used. The film chosen must match the format that the camera can accommodate. The main formats in common use are APS and 35mm. Many professional photographers and much older cameras will use square formats of various sizes.

(Film) Grain

It is actually the tiny particles of silver halide painted onto film as an emulsion that make film light sensitive. The coarser the particles are on the film, the more light sensitive the film will be because coarse particles react to light at a relatively high speed i.e. the faster the film will be. However the coarser the particles are, the more visible they become, making the end result look grainy. So a fast film will be more sensitive to light but will give a grainy result.

The reverse is true for slow film.

Film Speed (ISO)

The International Standards Organisation rating which identifies how sensitive a given film is to light. The higher the ISO number, the more sensitive the film is to light. A film, which is very light sensitive (with a high ISO number), is call “fast”, with “slow” film being less light sensitive (with a lower ISO number). So an ISO400 film is twice as fast as an ISO200 film and is better used when there is less light (because it is more light sensitive). Also see Grain.

· ISO100 and ISO200 films are the most popular and generally used as they perform well in good outdoor light and inside under flash.

· ISO400 is better in low light and at night; also for action shots where a fast shutter speed is required (because the film is fast, enough light will hit the film even though the shutter is only open for a short time)

· ISO800, ISO1600 & ISO3200 tend to be for specialist use in very low light or for where very high shutter speeds are required. They do produce very grainy results (which may be deliberately desired for a special effect)

· At the other end of the scale ISO020, ISO050 and ISO64 are used in very bright conditions, where a lot of detail is required (because they are low grain films) or where the image is to be blown up to a very large size (again accommodated by the low grain).

Note – The ASA (American Standards Association) ratings for film speed equate to the ISO rating i.e. 200ASA = ISO100. The old DIN (Deutsche Industrie Norm) system has been replaced by the ISO system.

Film Type

A term which usually refers to the medium of the end result e.g. “colour”; “black and white” (or “monochrome”) or infra-red film; “slide”/“transparency”/“reversal” film (all the same thing!) or “negative” film, which is also refereed to as “print” film. Also used in combination e.g. “colour print film”.

Infra-red film detects ‘heat’ and can be black & white based or colour based e.g. on the B&W version growing foliage appears white.

Negative film tends to be the popular format as its eventual outputs are in the form of prints, which are easily view, passed around and put in albums. Further reprints are easily and cheaply reproducible from the negatives also supplied.

The alternative is transparency film, which tends to be used by professionals and serious amateurs. The output is high quality and the original colours tend to be faithfully reproduced on the positive, which forms the slide in a one-stage process. The high quality means that it is slides that are used to produce photographs in magazines and books, not negatives/prints. Slides are also widely used amongst camera clubs, as projection through a slide projector onto a screen is most convenient for group viewing.

“Film type” may sometimes be used to refer to the film format or film type.

Filter

A glass or plastic plate placed in front of the lens to affect the way that the image as it will appear on the film. The effect depends on the type of filter. They can produce special effects or changes in colour or contrast.

Fixed Focus Camera

Simple cameras usually don’t include the ability to alter the focusing point. They are usually factory-set up to focus on a distant object (like a landscape) to allow for universal use.

Focusing

The method of adjusting the lens to get a sharp image; can be done manually or automatically on some cameras.

F-Stop

See Aperture

G

Glaze

The glossy surface on darkroom-produced prints; it enhanced that deepest blacks in the image. For digital printing, “glossy” papers try to emulate glazed photographic paper.

Grain

See (Film) Grain

H

Hand Held

Describes the process/photograph which has been taken whilst the camera has been held by hand rather than on a tripod. At fast shutter speeds (usually above ¹/₉₀ of a second) it is acceptable to hold a camera by hand for most common uses. Below that shutter speed or when a quality/guaranteed sharp image is required, the camera should be placed on a tripod to avoid camera shake.

Hotshoe

Usually found on top of the camera (in the case of an SLR); this accommodates the foot of a flashgun and contains the electrical contact, which allows the camera to activate the flash.

I

ISO

See Film Speed

L

Lens Hood

Attaches to the front of the lens to avoid glare from the sun.

M

Monochrome

Otherwise known as “black and white” – a film ype.

Multiple Exposure

The taking of more than one exposure on the same area (or frame) of film. A creative (or accidental!) technique.

N

Negative

An image where all the tones and colours are reversed.

P

PQI

See APS

Programmed Shutter

Aimed at achieving sharp results, this system automatically links the film speed, shutter speed and aperture setting to (usually) obtain a fast shutter speed.

Push (uprate)/Pull (downrate)

The technique of uprating or downrating the speed of a film by compensating during the development (processing) of the film. For example, a photographer may use an ISO050 film but push it by exposing it as though it was an ISO100 film. If this happens, the processing of the film has to be amended to make the film produce photographs as though it had been an ISO100 film that had been used.

S

Safelight

Used in the darkroom, it allows the darkroom worker a certain type (colour) of light, which will allow them see what they are doing without harming the light sensitive materials being processed. They tend to emit red or orange coloured light, to which most photographic materials are insensitive.

Shutter-priority

A facility on the camera by which the photographer sets the shutter speed and the camera automatically sets the aperture for a correct exposure.

Shutter Speed

The length of time for which the shutter is open (e.g. ¹/₉₀ of a second), thus governing the length of time for which the film is exposed to light. Fast shutter speeds freeze action; slow shutter speeds make action look smudged.

Slow

See film speed

Spot Meter

A light meter which takes a light reading of just a very small area of the subject

Stopping Up/Down

See Aperture

T

Telephoto

A lens that has a focal length such that it makes images appear closer than they seem with the naked eye or the standard lens of the camera. Also see Zoom

TTL (Through The Lens)

Through the lens light metering measures the light actually coming through the lens to try to obtain the most accurate exposure information for the shot.

V

Vignetting

The darkening or lightening of the edges of a photograph. Extremely small apertures can cause vignetting if care is not taken.

W

Wide Angle Lens

A lens that has a focal length such the field of vision is wider than it seems with the naked eye or the standard lens of the camera.

Z

Zoom Lens

A lens with a variable focus length, which effectively allows the view of the camera to be “zoomed” in and out. Lenses can we wide-angle zooms, telephoto zooms or lenses somewhere in the middle which can zoom between wide angle and telephoto.

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