Nikon D3400 Kit Owner's Manual

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16 First Steps
A
Lenses with Retractable Lens Barrel Buttons
Before using the camera, unlock and extend the lens. Keeping the 
retractable lens barrel button pressed (q), rotate the zoom ring as 
shown (w).
Pictures can not be taken when the lens is 
retracted; if an error message is displayed as 
a result of the camera having been turned 
on with the lens retracted, rotate the zoom 
ring until the message is no longer 
displayed.
A
Detaching the Lens
Be sure the camera is off when removing or 
exchanging lenses. To remove the lens, 
press and hold the lens release button (q) 
while turning the lens clockwise (w). After 
removing the lens, replace the lens caps and 
camera body cap.
Retractable lens barrel button