Camera controls-richard Flashcards
what is aperture
the amount of light passing through the lens of the camera
what is shutter speed
the amount of time the camera sensor is exposed to this light
what is ISO
the amount of digital or electronic amplification or gain applied to the electronic signal produced by the camera’s sensor.
aperture
the wider the aperture, the more light that can pass through
aperture settings are measured in f-numbers
the smaller the f number, the bigger the aperture and the more light that passes
each increase or decrease is known as ‘a stop’
what is the f number
focal length of lens(mm) / diameter of aperture(mm)
effects of changing aperture
can affect overall quality of an image
wide open lenses may produce images that are slight ‘soft’
as aperture is reduced the lens will produce sharper images
beyond this point the images become less sharp again due to diffraction.
changing aperture affects depth of field
what is depth of field
how much of an image is sharp and in focus
what is high DOF
object focussed on is pin sharp but also some or all of the foreground and background
what is shallow DOF
whilst the object you are focussing on is pin sharp, some or all of the foreground and background are blurred
Shutter speed
ensures camera is only exposed to light for a certain period of time - aim is to correctly expose the sensor
mechanical device which has 2 metal bladed curtains which move across the sensor and exposes it for a user-defined duration
when changes shutter speed, the camera varies the distance between the two curtains
the longer the shutter is open, the more light hits the camera sensor
exposure
correct exposure
underexposure
overexposure
what does ISO stand for
International Organisation of Standardisation
ISO
by increasing ISO, the camera normally applies amplification to the electrical signal from the sensor
problems with ISO
technical quality of an image drops as camera ISO increases
image becomes grainy and loses clarity and definition, often called noise
What is the reciprocal law
relationship between the shutter speed and aperture
doubling the time the shutter remains open or increasing the aperture size by 1 stop will double exposure
halving the time the shutter remains open or decreasing the aperture size by 1 stop will halve the exposure
