Samsung EV-NX1000BFWUS - Manual (Page 87)

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Shooting Functions >
Exposure compensation/lock
After locking the exposure, aim the lens where you desire, and press
[Shutter].
Exposure lock
When you cannot achieve an appropriate exposure because of a strong
color contrast, lock the exposure and then capture a photo.
To lock the exposure, adjust the photo's composition on which you
want to calculate the exposure, and then press the custom button.
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