Exposure is the biggest factor to take in consideration when you take a picture with your digital camera.
This is the amount of light falling on your sensor and it will determine how light or dark an image will appear when it’s been captured by your camera.
The exposure is determined by three camera settings – the aperture, ISO and shutter speed that work in synergy to take a perfect photo.
Mastering their use is an essential part of developing an intuition for photography.
The aperture, AV on most of the digital cameras’ dial and called F-stops, controls the area over which light can enter your camera.
When it is on the lowest numerial, like f3.5 the lens will be wide open and let in a lot of light.
The higher the number, like f22, the less light falls on the sensor.
Aperture affects depth of field and if you want a small portion of your photo in focus and the rest blurred, you will use the setting that has the lens opening at its biggest.
It you want almost everything in focus, you will use the f22 and higher to get a sharp focus on each part of the photograph.
The shutter speed controls the duration of the exposure.
It can be any thing from 1/4000 seconds to keeping open the shutter manually for as long as you want to.
To get enough light on your photograph, you have to get the right speed, usually a high speed for bigger F-stops.
The speed can also freeze fast moving objects when it is used at its highest or blur when used at its lowest property,
The ISO speed controls the sensitivity of your camera’s sensor to a given amount of light.
It affects image “noise”, the distance between the pixels or “dots” a photo is made of.
The higher the ISO, the bigger the “noise”, especially on the lower range cameras.
Digital cameras have price-tags added to those with high ISO values, because the higher the ISO value of a camera, the more you can do with available light.
It also means that you don’t have to use a flash or other external sources of light for your picture in low light situations.
There are many ways to use the combination of aperture, speed and ISO to achieve the same exposure.
The key is knowing which trade-offs to make, since each setting also influences the other exposure methods.
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