Exposure Triangle
The three elements in an exposure triangle are:
1. ISO – the measure of a digital camera sensor’s sensitivity to light
2. Aperture – the size of the opening in the lens when a picture is taken
3. Shutter Speed – the amount of time that the shutter is open
Aperture is a measure of how open or closed the lens’ iris is. A wider aperture (or lower f-number) means more light will be let in by the lens, because the opening is larger. A narrower aperture (or higher f-number) allows less light to reach the sensor.
Shutter speed is a measure of how long the shutter remains open and thus, how long the sensor is exposed to light. Faster shutter speeds give the sensor less time to collect light and thus, result in a lower exposure. Slower shutter speeds allow more time for the sensor to collect light and result in a higher exposure.
The ISO speed determines how sensitive the camera is to incoming light. Common ISO speeds include 100, 200, 400 and 800, although many cameras also permit lower or higher values. With compact cameras, an ISO speed in the range of 50-200 generally produces acceptably low image noise, whereas with digital SLR cameras, a range of 50-800 (or higher) is often acceptable.
The three elements in an exposure triangle are:
1. ISO – the measure of a digital camera sensor’s sensitivity to light
2. Aperture – the size of the opening in the lens when a picture is taken
3. Shutter Speed – the amount of time that the shutter is open
Aperture is a measure of how open or closed the lens’ iris is. A wider aperture (or lower f-number) means more light will be let in by the lens, because the opening is larger. A narrower aperture (or higher f-number) allows less light to reach the sensor.
Shutter speed is a measure of how long the shutter remains open and thus, how long the sensor is exposed to light. Faster shutter speeds give the sensor less time to collect light and thus, result in a lower exposure. Slower shutter speeds allow more time for the sensor to collect light and result in a higher exposure.
The ISO speed determines how sensitive the camera is to incoming light. Common ISO speeds include 100, 200, 400 and 800, although many cameras also permit lower or higher values. With compact cameras, an ISO speed in the range of 50-200 generally produces acceptably low image noise, whereas with digital SLR cameras, a range of 50-800 (or higher) is often acceptable.
How do I know what the correct exposure is?
Once you activate the camera meter by half-pressing the shutter release, the camera will suggest an exposure based on the brightness of the area being metered. This is usually expressed in the order of a shutter speed value at a given aperture and ISO - say 1/60 sec at f/8, ISO 200.
Once you activate the camera meter by half-pressing the shutter release, the camera will suggest an exposure based on the brightness of the area being metered. This is usually expressed in the order of a shutter speed value at a given aperture and ISO - say 1/60 sec at f/8, ISO 200.
Here are some over exposed photos I took:
This picture is bright and white because it is over exposed and it's not the correct exposure.