Nikon's D2H is the immediate successor to the D1H which was announced in February 2001 (along with the D1x) and reviewed by us in September of that year. The D1H built on the strengths of the D1 and added several new features including selectable color space, one-button playback, a new LCD monitor and others. However the biggest news about the D1H was the concept that it was a camera aimed specifically at sports and photo journalists who needed high frame rates and a large buffer. The D1H had the same sensor as the D1 (2.72 million effective pixels) but shot at five frames per second for up to 40 frames. The D1H was the class leader in its field and was only challenged by the 4.1 million pixel effective, 8 fps, 21 frame Canon EOS-1D which hit the shelves towards the end of 2001.
The D2H raises the bar even further, it has a brand new Nikon designed 4.1 million pixel 'JFET sensor' and is capable of capturing eight frames per second for up to 40 frames (five seconds of continuous shooting at 8 fps). The D2H also adds a whole lot more including a new eleven area AF module (Multi-Cam 2000), 37 ms shutter lag and just 80 ms viewfinder blackout, a new ambient external WB sensor, an orientation sensor, RAW + JPEG format, a huge 2.5" 211,000 pixel LCD monitor, a new lightweight Lithium-Ion battery (with detailed in-camera readout) and USB 2.0. The other 'big news' about the D2H system is the new WT-1 802.11b wireless transmission add-on which allows you to FTP images back to a server as you shoot them*.
* Buffered off the CF card with automatic reconnection on signal drop.
JFET LBCAST sensor
Nikon's new JFET (Junction Field Effect Transistor) LBCAST (Lateral Buried Charge Accumulator and Sensing Transistor array) sensor appears to be similar to CMOS technology but achieves higher speed data transfer allowing the camera's impressive eight frames per second shooting rate. Nikon claim it has:
- Instant Startup
- Higher Speed
- Higher Resolution
- Lower Power Consumption
- Low Noise (Minimal Dark Noise)
A little digging returned the following facts:
- The sensor was designed and developed solely by Nikon
- Research and development into this type of sensor started ten years ago
- The sensor has a 3-T (three transistor) design compared to Canon's 4-T (four transistor) CMOS sensor
- It is an X-Y Address-type Sensor with noise-cancelling functions
- The sensor uses JFET's instead of MOSFET's (CMOS normal) in the cell amps
- The sensor has microlenses and a low pass filter
- The sensor does not have an electronic shutter (requires a mechanical shutter)
While Nikon are currently keeping this exclusive sensor technology close to their chests they assure us that more detail and output from the LBCAST sensor technology will be made available later.
WT-1 Wireless Transmitter
As you can see from the image above the WT-1 attaches to the bottom of the camera via a tripod screw, there are power connectors on the base of the camera, the WT-1 uses the camera's battery for power. Digital connection is made by a short cable to the camera's USB 2.0 port (I was surprised by this, I would have thought it neater and relatively straightforward to include the USB 2.0 connection with the power connectors on the camera base). On this diagram a standard 'button' aerial is screwed into the WT-1's aerial socket but you can also use an extended range aerial which can be clipped to a backpack or jacket.
The D2H has support for FTP built into its firmware, there is a setup page which allows you to define the FTP server, username, password and folder to be used for upload as well as the image format to upload. For instance you can shoot RAW + JPEG and just transmit the JPEG via the WT-1. Images are written to the CF card first and then transmitted, in play mode the camera indicates images which are queued to be transmitted, which have been transmitted and the image which is currently being transmitted. The camera supports automatic reconnection should the wireless link be temporarily interrupted. In action the system is very impressive, the ability to be completely portable and yet see your images 'popping up' on a remote machine is an eye opener.
UPDATE: We have added our own experience of using the WT-1 on this page.