You notice the deeper you go, the lower the visibility. The darker the light conditions are, the higher the ISO. This makes your camera more sensitive to light and will serve to compensate for the absorption of light at depth.
Exposure Value (EV) also allows you to increase, or decrease, the camera’s light sensitivity. Increase EV to brighten images, and decrease EV to darken pictures. You may choose to increase the EV setting depending on depth, visibility or ambient light.
Depth | Visibility | Light | EV |
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20+ ft. (6m +) | bright, sunny | ||
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medium, cloudy | |||
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dark, night | 0 | ||
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NOTE: The color of your object will effect the brightness of your subject and the selection of your ISO or EV may be effected. Check you camera instructions for more information about ISO and EV
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