USBChoose a USB option for connection to a computer or PictBridgeprinter. Choose [MTP/PTP] (the default setting) when connectingto a PictBridge printer or an optional WT-4 wireless transmitter orwhen using Camera Control Pro 2 (available separately; see page368). See page 225 for information on selecting a USB option foruse with Nikon Transfer.Dust off Ref PhotoAcquire reference data for the Image Dust Off option inCapture NX version 1.3.5 or later or Capture NX 2 version 2.1.0 orlater (available separately; for more information, see the softwaremanual).[Dust off ref photo] is available only when a CPU lens is mountedon the camera. A lens with a focal length of at least 50 mm isrecommended. When using a zoom lens, zoom all the way in.318