Nikon D40 - Manual (Page 119)

Technical Notes/Caring for the Camera 107
On cold days, the capacity of batteries tends to decrease. Be sure the battery is fully charged before taking photographs
outside in cold weather. Keep a spare battery in a warm place and exchange the two as necessary. Once warmed, a cold
battery may recover some of its charge.
Continuing to charge the battery after it is fully charged can impair battery performance.
Batteries may leak or explode if improperly handled. Observe the following precautions when handling batteries:
• Turn the product off before replacing the battery.
• The battery may become hot when used for extended periods. Observe due caution when handling the battery.
• Use only batteries approved for use in this equipment.
• Do not expose the battery to flame or excessive heat.
Used batteries are a valuable resource. Please recycle used batteries in accord with local regulations.
Foreign Matter on the Low-Pass Filter
Nikon takes every possible precaution to prevent foreign matter from coming into contact with the
low-pass filter during production and shipping. The D40, however, is designed to be used with inter-
changeable lenses, and foreign matter may enter the camera when lenses are removed or exchanged.
Once inside the camera, this foreign matter may adhere to the low-pass filter, where it may appear in
photographs taken under certain conditions. To protect the camera when no lens is in place, be sure
to replace the body cap provided with the camera, being careful to first remove all dust and other for-
eign matter that may be adhering to the body cap.
Should foreign matter find its way onto the low-pass filter, clean the filter or have it cleaned by autho-
rized Nikon service personnel ( x). Photographs affected by the presence of foreign matter on the
filter can be retouched using Capture NX (available separately; 103) or the clean image options
available in some third-party imaging applications.