February, 2001. Nikon unveiled their 2nd generation Professional Digital Still SLR camera – the Nikon D1x, which incorporated a 5.47 million effective pixels. The image resolution was greatly improved from the original 2.74 mega pixels D1, which was first introduced back in 1999. One of the many interesting fact was, along with the official debut of D1x, Nikon also took the opportunity to introduced a sister model that has a slight different configuration which labeled it as Nikon D1H. As the name suggested, basically, the primary model, D1x was designed for resolution/image sharpness while the D1H was optimized more for fast workflow.

The Nikon D1x also has an enhanced model (upgrading firmware) introduced in late 2002 , which contains a far greater memory buffer and offers at least 200% improvement in 3 fps continuous-drive image handling. The immediate benefit is, 21 JPEG images or 14 Raw images can also be shot at the moderately fast 3 fps shooting rate. A D1X cameras with the buffer upgrade will show the firmware setting as Version. 5.01