Just picked up the hobby(photography), can some explain these terms and how the affect each other?
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A camera captures an image by recording light that passes through the lens onto the sensor.
ISO: the sensitivity of the sensor to that light. Higher ISO turns up the gain and makes the sensor more sensitive to the light.
Aperture: the size of the opening in the lens that the light passes through. A smaller number is a bigger opening. A bigger number is a smaller opening.
Shutter speed: the amount of time that the shutter is open, allowing light to pass through the opening in the lens onto the sensor.
You control exposure by adjusting these variables.
1/100 shutter speed and f/8 aperture gets you the same exposure as 1/200 shutter speed and f/4 aperture. You’ve halved the amount to time that light is allowed to flow onto the sensor, but you’ve doubled the size of the opening in the lens so twice as much light can flow through.
1/100 shutter speed at f/8 aperture and ISO 100 gets you the same exposure as 1/200 shutter speed at f/8 aperture and ISO 200. You’ve left the lens opening at the same size, so the same amount of light is flowing through. You’ve cut the amount of time that the light can flow onto the sensor in half, but you’ve doubled how sensitive the sensor is to that light.
There are lots of other things going on when you make adjustments to these variables, but this is how they relate to exposure.
Buy the book Understanding Exposure by Bryan Peterson. It’s been one of the most common reads for new photographers for the past 20 years.
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