| Air brushing |
Traditionally this was the process of spraying
a fine jet of dye onto areas of film or a
print to change the appearance of an image.
i.e. fix flaws in a models skin, or smooth
out paintwork on a car. This process now takes
place digitally within photo manipulation
software, however it is still commonly referred
to as air brushing. |
| Ambient lighting |
Refers to the levels of light that already
exist within a scene to be photographed, without
the addition of any photographic lighting. |
| Aperture |
A window of (usually) varying diameter at
the front of a camera that lets in light.
The aperture is typically found within the
lenses of any camera. Changing the size of
the aperture is one way of adjusting the exposure
of an image. Inversely proportional with Shutter
Speed when determining exposure. |
| Aspect ratio |
The ratio between the height and width of
an image. The most typical aspect ratio is
2:3 meaning that for every 2 units of height
there are 3 units of width. This is the aspect
ratio of 35mm format. |
| Camera format |
Typically refers to the size of the film
or digital chip used to capture the image,
although there has been some carryover from
film measurements. i.e. some digital cameras
are described as 35mm format, even when they
have a smaller chip size. |
| Capture plane |
The point at which a photographic image
is "captured", either on digital
chip, or to film. When referring to film it
is typically called the "film plane". |
| Depth of Field |
The range of depth within an image that
displays apparent sharpness. |
| Extension tubes |
Tubes that connect between a lens and camera
body to extend the distance between the back
lens element and the image capture plane.
Used for macro photography. |
| Generation |
Each stage in the workflow of an image,
where the information is tranferred to a different
medium is classified as a generation. i.e.
transferring from film to digital file by
way of scanning, or printing from a file to
hardcopy are each a generation step and are
accompanied by a drop in quality. One of the
benefits of digital capture is that it reduces
the number of generation to final output.
i.e. no scanning. |
| Giclee |
A term commonly used in reference to high
end art digital prints. Effectively a high
quality inkjet (or similar process) print. |
| Grey Card |
A card with a midtone, or 18% grey. Used
to determine exposure readings with an in-camera
light meter. In-camera light meters are calibrated
to this midtone grey, meaning that whatever
scene is being viewed, the camera assumes
it will all average out to 18% grey. |
| Hero |
When viewing a proof sheet or selection
of images, the Hero image is the image selected
for final use. i.e. typically the best image
from the selection. |
| Image Resolution |
Referred to in "ppi" (pixels-per-inch)
or also "dpi" (dots-per-inch). Image
resoltion is a measurement of pixel density
in an image. For final output descriptions,
a ppi or dpi figure has no meaning without
a corresponding image size. i.e. a 4"x
6" image at 300ppi is 1200 x 1800 pixels.
An 8"x 12" image at 150ppi is also
1200 x 1800 pixels. Both images have the same
amount of information and will reproduce identically. |
| JPEG |
A commonly used file format. Please view
our page on file
formats for more information. |
| Lossless |
Refers to a particular type of file format
that does not disgard information upon saving,
even when compressing to reduce file size.
Please view our page on file
formats for more information. |
| Lossy |
Refers to a particular type of file format
that disgards information upon saving in order
to reduce file size. Please view our page
on file
formats for more information. |
| Macro photography |
Photography where the size of the subject
on the capture plane is similar or greater
than the real size of the subject. |
| Nanometre |
One billionth of a metre (or one millionth
of a millimetre). Used to describe wavelengths
of light (or anything else very very small). |
| Pixel |
The smallest element of a digital image.
Digital images are composed of many thousands
or millions of pixels. |
| RAW |
A commonly used file format for capturing
images in high end cameras. Please view our
page on file
formats for more information. |
| Shutter |
A window that opens to allow light to expose
the image capture plane. Usually within the
body of a camera, though with some formats,
can be contained within the lense. |
| Shutter speed |
The length of time that the shutter opens.
Determines the amount of light that reaches
the image capture plane. i.e. the longer the
shutter is open, the more light that reaches
the capture plane. Inversely proportional
to aperture settings when determining exposure. |
| Speed |
Refers to the sensitivity of film or digital
chip to light. The higher the number the more
sensitive, and therefore the less light required
to make an accurate exposure. |
| TIFF |
A commonly used file format. Please view
our page on file
formats for more information. |
| TTL |
Or "Through the Lense". Refers
to a type of light-metering that occurs in-camera
with light that has passed through the lense,
thereby taking into consideration the characteristics
of the lense and camera settings. |
