GoPro HERO 4 Black User Manual page 67

Protune for Photo ISO Limit
Setting
800 (default)
400
200
100
SHARPNESS
Sharpness controls the sharpness of your video footage or photos.
Sharpness Setting
High (default)
Medium
Low
Lighting Condition/Resulting Quality
Darker photo in very low light, increased
image noise
Darker photo in low light, moderate image noise
Bright photo in indoor lighting, marginal
image noise
Bright photo in outdoor daylight, minimal
image noise
Resulting Quality
Ultra-sharp video or photo
Moderately sharp video or photo
Softer video or photo
/ Protune
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