shutter speed, aperture, depth of field

Shutter speed

The shutter speed is the amount of time in which the shutter opens and closes. The shutter speeds is measured in fractions of a second e.g. ¼, ⅕ or 1/30 of a second. The slower the shutter speed the more light will enter the camera, the quicker the shutter speed, less light enters the camera. You can change the shutter speed to a slower or faster speed depending on what you are going to take a photo of. you normally require faster shutter speeds when taking a picture of fastest action or certain sports sport in bright lighting.  Slow shutter speed letting more light get into the picture, but has the potential risk of ‘camera shake’.  Camera shake is when the shutter slow shutter speed records fractional movements of the camera making the image blurred, or as if the whole image is moving.  Fast shutter speed captures fast-moving objects before it goes away.

Depth of field 

The smaller the aperture (hole) or ‘f stop’ the greater the depth of field which means more of the picture is in focus.  The depth of field is a measure shown on camera lenses of distances that will be in focus in front and behind the item you focus upon.   The larger the aperture the shallower the depth of field. This means things in front or behind the subject will be out of focus.  You can change the depth of field so you can get the background in focus plus the subject and the foreground out of focus.

 

shallow depth of field.

Deep depth of field

ISO – IInternational Standards Organisation

The ISO number is refers back to emulsion film photography and how light sensitive the film is.  Higher the ISO number the more the camera is sensitive to light, in other words it can take pictures at much lower light levels.  This is useful when taking either photographs where the light is poor or you are taking fast action shots and need to use very fast shutter speeds to freeze the action.

The lower the ISO the less sensitive the camera is to light.  This is useful when photographing images in very bright light such as snow scene or bright sunny days and there is a lot of light reflected.

The ISO numbers go up from 64, 100, 200, 400, 800, 1600, Each increase doubles the light sensitivity.  The numbers are still used in digital photography and relate to the cameras adjustments and sensitivity to light.

A connected fact about the ISO speed is the quality of the image recorded by the camera.  A high ISO speed will result in a lower picture quality with noise or elements of the image are incomplete giving a grainy image. Slower speeds the image saturates and gives very high quality definition images.

The altering of the ISO settings especially to the fast ISO speeds can give interesting grainy effects, similar to water colours because the image is not fully saturated with colour image.

White balance 

We measure white balance in Kelvin which in other terms is known as the Kelvin scale.  If there are two conflicting colours then that is called a colour cast which will appear in the picture . white balance is when you get un natural light mixed with natural light and disturbs the picture and makes the colour balance un even in the picture. you can create white balance  if you put all of the primary colours with the scam amount of colour and brightness to create a white colour this is used in the camera flash. white balance is also telling the camera what is wight so the camera can function round the different colours.

If you are photographing under artificial light, different types of lighting give different colour effects.  Flourescent tube lighting makes images appear with a cold green hue.  Tungsten light bulbs give an over warm orange hue to images.  If a white balance is performed before you take the shot the camera can compensate for these colour changes.

if you don’t have enough of a certain colour then you can change the colour of the photo causing the picture to look out of place and unnatural.