Saturday, April 11, 2009

Short Glossary of Camera Settings and Techniques

This glossary is in alphabetical not in logical order,
You might want to use it before you buy a new camera or lenses or to come to terms with some of the important settings on your camera.

The aperture in your camera is an opening of variable size where the light enters the camera (like the iris in your eye, only made of metal blades).
The size controls the amount of light coming in at a set time (shutter speed).
Now- the confusing part is the numbers on the standard scale, the f-stops:
f/1 f/2.8 f/3.5 f/5.6 f/8 f/11 f/16 f/22 f/16 f/22 f/32 f/45 and f/64
The higher the number - the smaller your aperture gets,
f/1 would let in the full amount of light and f/64 the least.
Aperture determines the sharpness of a picture:
the smaller the aperture (number becoming bigger) –
the more of a picture is in sharp focus.

Compact camera:
Camera (mostly digital now) with fixed lens, often zoom.
Single Lens Reflex camera using film.
Digital Single Lens Reflex camera using a sensor.
Both SLR and DSLR have interchangeable lens systems
that allow a wide range of different focal length lenses to be used with the camera.

Depth of field
This is the amount of sharpness throughout your picture.
It is controlled by your aperture settings only;
A small aperture (big number) brings more of the subject into sharp focus.
Depth of field is a creative tool to put more or less emphasis on parts of the subject.
If you only want part of your subject to be in sharp focus, use a bigger aperture (smaller number).

The amount of light a picture receives controlled by lens aperture and shutter speed.
A picture gets the same exposure e.g. with
f/5.6 (aperture) and 1/125sec (shutter speed) as it would get with
f/8 (smaller aperture) and 1/60sec (slower shutter speed).
The ISO setting on your camera (digital) or on the film plays a roll too, a higher setting allows you to take pictures in darker environments but they will look more “grainy”.

Focal length of a lens
A lens focuses light at a specific distance.
It is normally marked on the lens barrel in millimeters:
lenses marked up to 35mm are a wide angle lenses (used to include large areas of a scene such as landscapes)
40-55mm are “normal” lenses (because they see about the same as the human eye)
above 75mm you have telephoto lenses (they allow you to isolate areas of a scene because the viewing angle gets smaller or take in distant subjects).

Lenses with fixed focal length:
Cover just that distance
(achieve better quality but you need more than one lens for
your camera depending on what kind of picture you want to take-
remember you cannot change lenses on compact cameras).

Zoom lenses: cover a range of focal length, e.g. 70-210mm
(but the bigger the range of a zoom lens the harder to keep image quality-
the quality of an image taken with a fixed lens of 135mm is better than with a zoom lens
set at 135mm)

States a films sensivity to light and has been adopted to digital photography to represent the response of a digital sensor to light.
With ISO 400 you get 4 times the light sensitivity of an ISO 100 setting,
so the lower an actual light level the higher ISO you might want to use.

Raw or Jpeg
Shoot RAW and you get a file with all the data captured by the image sensor
but you need more capacity on your memory card and you need to process the RAW file before you can print it.
JPEG images can be used and printed immediately, they need less capacity, so more will fit on your card.

Shutter speed
The length of time light is allowed to fall on the sensor inside the camera, represented in seconds and fractions of seconds.
1/8000sec is the shortest possible time and 30 seconds the longest in preset. If you want longer times in dark conditions press B(bulb).
Be careful to avoid camera shake, with longer times you might want to use a tripod.
Shutter speed is used to control the overall exposure (together with aperture).
It can also be applied to get special effects, e.g. with a slow shutter speed subjects which are moving begin to blur, like flowing water or moving car lights -
On the other hand you can freeze an action in sports with a fast shutter speed.

White balance
Allows to adjust the way in which a camera records the colours in a scene.
There are usually preset settings for sunshine, overcast, day light or tungsten, which is artifical light, etc.