Glossary

Photography & Digital Photography glossary

The following is a glossary of commonly used digital photography and photography terms.
You may click on some of them to see an in depth tutorial that you can do yourself to better apply and understand the application of that term.
If any information herein has been miss-represented please contact the Web master.


AE Lock - Auto Exposure lock
This term refers to a button on the camera which, when pressed will hold the exposure at the current value until a photo is taken or it is disabled.

AF Lock - Auto Focus Lock
This term refers to a button on the camera which, when pressed will hold the focus at the current value until a photo is taken or it is disabled.

Aperture *tutorial upcoming
This refers to a mechanical opening which opens and closes in order to let more or less light through. It is also referred to as the F-Stop. Each opening is represented by a number where the larger the F# the smaller the opening. F2 for instance allowing a substantial amount of light to pass through and F11 allowing less light through. The aperture is directly related to the amount of depth of field.

Aperture Priority (A or AP)
Represents a setting (normally found on the main mode dial) which allows the user to manually set the Aperture size and gives control of the shutter speed to the camera, allowing it to set the best speed for the current lighting conditions. This setting is normally used when the photographer wants greater control over their depth of field.

Artifacts & Artifacting
Distortion in colour or line causing caused by image compression. Leads to poor quality image.

Auto - Automatic
This is a term that refers to a setting on almost all cameras which allows the camera to choose all or almost all the settings.

Barrel distortion
Lenses can cause different types of distortion on an image which includes barrel distortion or barelling which is when the edge of the image bows towards the outside.

Battery
There are two main types of batteries which are rechargeable and disposable and several different kinds of these.

*Rechargeable battery tip: When you will not be using a rechargeable battery for more than a week or two make sure it is completely discharged. Even though almost all new rechargeable batteries have gotten rid of the "memory" problem there is always some seepage and leaving a half charged, or even worse a fully charged battery without using it for extended periods will cause it to decrease it's full capacity.

Calibrate
Calibrate or calibration refers to the task of obtaining the same colour results from one device to another. One of the harder tasks in digital photography is to obtain the same colour results from your screen or camera to your printed image.There are several different ways of doing this, the more expensive being high end colour calibration tools.

Center-wighted metering
Type of metering where the camera meters the whole image area but puts the most importance on the middle of the image.

CCD - Charge coupled device
This is a light sensitive chip that gathers light to create a digital image. The CCD in a digital camera replaces a piece of film even though normally the memory card is seen as the film because it stores the images, the CCD is the actual device that originally captures the light from the lens.

CMYK - Cyan, Magenta, Yellow and Black
CMYK is the printed spectrum of light as opposed to RGB which is the visible spectrum of light.

Default
Refers to the standard or factory settings for any given device.

Depth of field *tutorial upcoming
The area of acceptable focus. The amount of depth of a photo in front and behind the subject that is in focus.

Digital zoom *tutorial upcoming
An enlargement of an image that is enhanced digitally. Quality of a digitally enhanced image is very poor compared to that of an optical enlargement.

DPI
Dots per inch - This refers to the resolution of an image. The more dots in an image the better the quality is. 300dpi is very similar to the quality in an actual photograph.

*Information: The default DPI of a display hooked up to a computer is 72 DPI for Mac computers and 96DPI for Windows based machines. This means that an image which is 1inch by 1inch at 300DPI will appear much larger on the screen.

DSLR - Digital Single Lens Reflex
Type of camera which allows the photographer to view the actual image through the lens of the camera via a mirror set up.

Dynamic range
The difference between the brightest and lightest pixels in a photo. AKA Contrast

Effective pixels
The number of pixels that are exposed on the sensor and that are seen in the final images after processing.

EV - Exposure value
The amount of shutter speed or aperture needed to double or half the amount of light that will expose your picture.

EXIF - Exchangeable Image File
Information imprinted on a digital photo and contains information such as the date, shutter speed aperture etc at which a picture was taken

Exposure
The amount and length of time that light will expose the film or sensor thusly creating a light impression or photograph. Exposure is determined by shutter speed and aperture settings.

Fill in flash
Refers to using only a small amount of flash in order to help better expose an image. Fill in flash is normally used in photos where the subject has the sun behind them.

Filter
Filters are additions that attach to a lens in order to filter light for different reasons.
Examples of common filters are a polarizing filter that removes light at certain angles to obtain an image without glare from windows and with enhanced colours.

FireWire
Apple created this file transfer protocol. It is extremely fast and comparable to USB 2.

F-stop - F-number
The ratio of the aperture.
The F-Stop is the size of the aperture which opens and closes to allow more or less light to pass through. The F-Stop (aperture) with other elements is used to control depth of field.

Focal length *tutorial upcoming
The magnifying power of a lens

GIF - Graphic image file
Image compression type that supports only up to 256 colours and is used for line art as opposed to photographs.

Interpolation
Cameras or image editing software enlarge photos by interpolating them. This means to add pixels around an existing pixel, in order to allow the image to become larger. Bilinear=nearest neighbor. Bi cubic.

ISO - International Organization for Standardization
A sensors (CCD, CMOS) sensitivity to light. Ranges from 50 to 1600 are common with 3200 and 6400 being quite high. This also determines the amount of noise in a photo.

JPG - JPEG
A lossy compression type common in digital cameras.

Light Meter
Small handheld device allowing the photographer to see the amount of light needed to expose a photo.

Megapixel - A measurement of size and resolution. One megapixel is one million pixels. you can determine the megapixel size of your camera by multiplying its pixel width by it's pixel height.

Meter - Light meter - Metering - Meter reading
There are different kinds of light meters including in camera and hand held devices. These meters calculate the amount of light needed to correctly expose an image. However light meters can be fooled, check your images after taking them to be sure to have correct exposure.

Number of total pixels (total pixels)
Corresponds to the amount of total pixels on a sensor. Not all these pixels will be seen on the final image. Shows the sensor size as opposed to the final image size.

Optical zoom
Enlargement of an image done with glass only which keeps the quality of the enlargement as opposed to digital zoom.

Point and shoot camera
Cameras, normally without the ability for manual aperture or shutter speed settings.

Priority Auto
Camera mode which allows the camera to do the metering of the photo and allows the user to override most settings.

Prosumer
Refers to a camera which has settings similar to an SLR camera. Pro refers to the professional settings that allow you to control the camera exposure.

RAW (Raw image file)
This refers to an image captured from a digital camera that has not been processed. This image has more quality than a JPEG image since it has not been processed and thusly lets the photographer manually change the settings for it.

RGB
Literally: Red, Green, Blue. Refers to the visible spectrum of light. Monitors and projection TVs use these three colours of light to create the picture.

Shutter lag
A amount of time it takes between when you depress the shutter button to when the photo is actually taken

Shutter priority (P or SP)
Allows the photographer to manually set the shutter speed and the camera will compensate with the correct exposure by setting the aperture. Normally used to control the action of a photo such as a fast moving car with a blur because of it's motion or a bird caught in mid-flight.

Slow sync flash
Flash setting where the shutter opens and then the flash fires prior to closing

Start up time
The amount of time it takes the camera from being off to being able to take a picture.

SLR (see also DSLR)
Single lens reflex. A type of camera that uses a mirror system to show the photographer the image through the lens taking the photo.

Spot metering
Type of metering where only a small (programmable) area in the middle of the frame is used for metering.

White balance
Settings on a camera that allow the user to adjust the light hitting a photo to resemble the most realistic colours possible.

Cameras will also show this with settings for specific scenes such as: Cloudy, Tungsten, or Flash. White balance is also measured in Kelvin temperature examples of which being - K3200 indoor light - K5600 outdoor daylight - K6000 flash photography the higher the # the cooler the temperature


If any information herein has been miss-represented please contact the Web master.