The Nikon D1 is a digital single-lens reflex camera (DSLR) made by Nikon Corporation introduced on June 15, 1999. It featured a 2.7-megapixel image sensor, 4.5-frames-per-second continuous shooting, and accepted the full range of Nikon F-mount lenses. The camera body strongly resembled the F5 and had the same general layout of controls, allowing users of Nikon film SLR cameras to quickly become proficient in using the camera. Autofocus speed on the D1 series bodies is extremely fast, even with "screw-driven" AF lenses. Although Nikon and other manufacturers had produced digital SLR cameras for several years prior, the D1 was the first professional digital SLR that displaced Kodak's then-undisputed reign over the professional market. Unusual for a DSLR, the D1 uses the NTSC color space instead of the conventional sRGB or Adobe RGB color spaces. The resulting color on the D1 can be a bit unorthodox, but methods of correcting and/or compensating for the color problem are readily available. D1H and D1X The D1 was replaced by the D1H and D1X on February 5, 2001. The D1X offered higher resolution with a 4,024 x 1,324 - 5.3 effective megapixels sensor (3,008 x 1,960 interpolated image output), and continuous shooting of 3 frames per second for up to 21 consecutive shots. The D1H was oriented towards fast-action photography, keeping the same 2.7 megapixels image sensor as the D1, but pushing the frame rate to 5 frame/s for up to 40 consecutive shots. Both the D1H and D1X use the sRGB/AdobeRGB color spaces, which is an improvement over the original D1. Development and sensor design Development began on the D1 in 1996, when digital imaging was in its infancy in the consumer market. At that time the major market leader for DSLR cameras was Kodak, who produced their own image sensors and assembled digital cameras under the brand Kodak DCS. The DCS cameras were based upon 35 mm SLR cameras, replacing the film back with one incorporating a CCD sensor. This in turn was connected to a power supply and image processing and storage unit that was either carried separately or attached to the base of the camera body. While these cameras offered the convenience of digital imaging to normal photographers, their appeal was limited by huge price-tags and issues with sensor size, resolution, and performance in comparison to film. Nikon therefore stood to gain a significant market advantage if they could manage