Nikon D40 Guide User Manual page 117

The Low-Pass Filter
The image sensor that acts as the camera's picture element is fitted with a low pass filter to
prevent moir6. If you suspect that dirt or dust on the filter is appearing in photographs, you
can clean the filter as described below. Note, however, that tile filter is extremely delicate
and easily damaged. Nikon recommends that the filter be cleaned only by Nikon authorized
service personnel. To prevent the camera from powering offwhile the mirF)r is raised, use a
full charged battery or an optional EH 5 AC adapter and EP5 AC adapter connector (_ 103).
1 %move tile lens and turn tile camera on.
2 Select Mirror lock-up flora the setup menu (note that this option is not available at
battery levels of Q or below).
Highlight On and press OK. Tile message shown at right will
be displayed. To restore normal operation without inspecting
tile low pass filter; turn tile camera off.
4
Press:he shutter release button all tile waydown. Tile mirror
will be raised and tile shutter curtain will open, revealing tile
low pass filter.
S Holding the camera so that light falls on tile low pass filter,
examine tile filter for dust or lint. If no foreign objects are
present, proceed to Step 7.
Remove any dust and lint from tile filter with a blower. Do not
use a blower brush, as tile bristles could damage tile filter:
Dirt that can not be removed with a blower can only be
removed by Nikon authorized service personnel. Under no
circumstances should you touch or wipe tile filter.
7
Turn tile camera off. Tile mirror will be lowered and tile shutter curtain will close.
Replace tile lens or body cap.
Usea ReliablePewerSource
The shutter curtain is delicate and easily damaged, if the camera turns off with the mirror raised, the
curtain will dose automatically. To prevent damage to the curtain, observe the following precautions:
o Do not turn the camera off until cleaning or inspection is complete. Do not remove or disconnect
the power source while the mirror is raised,
. if the battery runs low while the mirror is raised,a beep will sound and the AF-assistilluminator will
blink to warn that the shutter curtain will close and the mirror will be lowered after about two mira
utes. Endcleaning or inspection immediately.
TechnicalNotes/Caring for the Camera 105