| Item |
Abbreviation |
Description |
| Aspect Ratio |
|
The ratio between the width and height of an image. |
| Background |
|
Whatever appears behind the main subject of a photograph. |
| Blur |
|
A lack of sharpness in the image caused by a missed focus or by the camera or subject movement during a slow shutter speed. |
| Brightness |
|
Describes how light or dark we perceive a colour to be. The higher the brightness, the closer the colour will be to white. |
| Compression |
|
Storing image data in a way that results in a reduction in file size. Compressing data is especially important when you want to publish images on websites. GIFs, JPGs and PNGs are all common compressed file formats. |
| Contrast |
|
The difference between the darkest and lightest areas in a photograph. The greater the difference, the higher the contrast. |
| Cropping |
|
An image-editing technique whereby a portion of a photograph is removed, usually from the outside of the image, to eliminate unwanted details. |
| Depth of Field |
|
The area in front of and behind the main subject of a photograph that remains in focus. |
| Dots per Inch |
DPI |
A measurement of the resolution of a digital photograph. The higher the DPI, the better the detail of an image. It is a measurement of the number of dots found in a one-inch square of an image. |
| Downloading |
|
The process of transferring images from a digital camera to a computer. Once an image has been downloaded it is saved to the computer's hard disk. |
| Exposure |
|
The amount of light that your camera captures while taking a picture. Too much light can create an overexposed image (too bright) while not enough light can result in an underexposed (too dark) photograph. |
| Gigabyte |
GB |
A measurement of data storage equal 1,024 megabytes (MB). |
| Graphics Interchange Format |
GIF |
A standard for compressing image data. Because of their limited colour depth, GIFs are better suited for images made up from solid colours such as logos, icons, and text. |
| Grayscale |
|
A photograph made up of varying tones of black and white. |
| Highlights |
|
The brightest parts of a photograph. |
| Image Format |
JPG, GIF, PNG |
The manner in which digital images are stored. There are numerous ways to store an image, and the most popular that are used on websites are JPG, GIF and PNG. You can identify which format is used by looking at the end of the file name after the dot, for example, picture.jpg is a jpeg file. |
| Image Resolution |
pixels |
The number of pixels in a digital photograph is often referred to as its image resolution. |
| JPEG |
JPG |
A standard for compressing image data developed by the Joint Photographic Experts Group. Image file names using the JPEG compression will have a file extension of .jpg. |
| Megabyte |
MB |
A measurement of data storage equal to 1024 kilobytes (KB). |
| Megapixel |
|
One-million pixels, a unit of measurement in an image. |
| Pixel |
|
Short for Picture Element. Digital photographs are made up of thousands or millions of them - they are the building blocks of a digital photograph. |
| Portable Network Graphic |
PNG |
The PNG file format is a great alternative to the GIF format. PNGs compress bitmaps without loss and also support transparency and 24-bit colour. |
| Red-Eye |
|
The red glow from a subject's eyes caused by light from a flash reflecting off the blood vessels behind the retina in the eye. |
| Resizing |
|
Changing the dimensions of an image (measured in pixels) to make it larger or smaller. |
| Saturation |
|
The richness of colours in a photograph. |
| Sharpness |
|
The clarity of detail in a photograph. |
