Nikon D3100, User Manual, Page: 281 / 318

189
n
Focus does not lock when shutter-release button is pressed halfway
: Use
AE-L/AF-L
button to lock focus
when live view is off and
AF-C
is selected for focus mode or when photographing moving
subjects in
AF-A
mode (
0
60).
Can not select focus point
:
•
e
Auto-area AF selected for AF-area mode > Viewfinder (
0
58), or Face-priority AF
selected for AF-area mode > Live view/movie (
0
38): choose another mode.
• Press shutter-release button halfway to turn monitor off or activate exposure meters (
0
27).
Subject-tracking AF not available
: Select a non-monochrome Picture Control (
0
94).
Can not select AF-area mode
: Manual focus selected (
0
38, 55).
Image size can not be changed
: Image quality set to NEF (RAW) or NEF (RAW) + JPEG fine (
0
65).
Camera is slow to record photos : Turn noise reduction off (
0
134).
Noise (randomly-spaced bright pixels, fog, or lines) appear in photos :
• Choose lower ISO sensitivity or turn noise reduction on (
0
134).
• Shutter speed is slower than 8 s: use noise reduction (
0
134).
Smudges appear in photographs
: Clean front and rear lens elements. If problem persists, perform
image sensor cleaning (
0
180).
Date is not imprinted on photos : Image quality set to NEF (RAW) or NEF (RAW) + JPEG fine (
0
65,
147).
Sound is not recorded with movies
: Off is selected for Movie settings > Sound (
0
47).
Flicker or banding appears during live view or movie recording : Choose an option for Flicker reduction
that matches the frequency of the local AC power supply (
0
139).
Menu item can not be selected
: Some options are not available in all modes.