ISO
ISO represents the sensitivity of your camera’s digital sensor to light. ISO stands for International Standards Organization. The lower the number (ISO 100), the less sensitive the sensor is to light and the higher the ISO number (ISO 3200) the more sensitive the sensor is to light.
•A low ISO produces the most detailed images. Use outdoors, in brightly lit environments or with a tripod.
•Use ISO 400 to 800 for extra sensitivity with little image degradation.
•Use ISO 1600 and above for low light photography without flash or for stopping action (very high image noise).
As shown in the chart below if you double the ISO value you increase the sensitivity of the sensor by +1 f/stop or +1 EV (**Exposure Value). Conversely when you cut the ISO value by one half you will decrease the sensitivity of the sensor by -1 f/stop or -1 EV.
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