Sony's XDCAM HD system

Sony Electronics' XDCAM HD line of products is designed to fill an important marketplace void. The system delivers an affordable mid-range high-definition production solution to professionals who either need more than an entry-level HDV option or can't afford or don't quite need the full functionality and image quality of a higher-end system such as the HDCAM SR.

This is Sony's second generation of the XDCAM Professional Disc system. Broadcast, cable and other organizations have adopted XDCAM for their ENG and operations.

Now with the introduction of an HD version of XDCAM technology, broadcasters as well as cinematographers and video professionals can combine the benefits of an IT-based optical production chain with high-definition resolution, providing a pathway as the demand for HD content increases.

The new XDCAM HD system includes two camcorders and two decks. The same Professional Disc media used in the standard-definition version of the XDCAM system is also used in the new HD version, providing up to two hours of HD MPEG-2 Main Profile Long GOP content.

The system offers a choice of 18Mb/s and 35Mb/s variable bit-rate recording and 25Mb/s constant bit-rate recording, similar to the HDV tape system. Recording times are approximately 120 minutes (18Mb/s), 90 minutes (25Mb/s) and more than 60 minutes (35Mb/s). The system also records four channels of uncompressed, 16-bit/48kHz audio. At these data rates, the XDCAM HD system is able to work within many existing 25Mb/s DVCAM systems.

Both camcorders in the XDCAM HD line-up — the PDW-F350 and PDW-F330 — share several key features, including true 24p recording, interval recording, slow shutter and SD/HD recording. Both camcorders also feature three 1/2in, 1.56 million pixels, as well as Power HAD HD CCDs. In addition, both are capable of recording 1080i video at multiple frame rates. The PDW-F350 and PDW-F330 both shoot at 24p, 25p and 30p in addition to 50i and 60i.

The new camcorders also build upon several features that have been XDCAM staples from the start. Among these are immediate random access to data in the field; the ability to easily browse footage as thumbnails and preview content on the camcorder's LCD screen; and high-speed transfer of proxy A/V and high-resolution data using the MXF file protocol.

Another familiar feature is the use of proxy A/V data. The system records a lower resolution, frame-accurate version of high-res content that can be transmitted or FTPed, allowing editors to begin compiling EDLs without having to wait for the discs to arrive from the field.

Within the new XDCAM HD camcorder, users can perform time-lapse recording without the need for an external intervalometer. For example, shooting 1fps can portray a fast-paced lifestyle, and shooting one frame per day condenses timeframes that in real time stretch out over days or months into mere seconds.

The PDW-F350 adds variable frame rate recording, which allows users to perform slow and quick-motion functions at a range of frame rates from 4fps to 60fps in one-frame increments.

This is similar to overcranking and undercranking with a film camera and allows the shooting frame rate to be different from the playback frame rate. The ability to perform this function directly through the camcorder means that in post, for example, additional steps or external frame-rate conversion is not required. Shooting at 4fps for 24fps playback produces motion six times faster than real time, and shooting at 60fps for 24fps playback produces motion at 40 percent real-time speed.

News or documentary shooters often need to work with pool feeds, where a single clip might run for more than an hour. To make finding a point within a clip easier and faster, the expand function indexes a clip into 12 even time intervals, with 12 instant-access thumbnails showing the first frames of each of these 12 time divisions. These clips can be further indexed into 1,728 evenly spaced time intervals with thumbnail pictures.

News crews have limited or no control over the conditions they're shooting in, and that often translates to low light. To overcome this challenge, the slow shutter feature acts essentially as super gain, accumulating from two to 64 frames at a time and recording the results. By accumulating several frames, it's possible to emphasize motion with added blur; group more frames to create a fantasy or ghost-like effect; and effectively turn night into day and reveal noise-free color and detail in a scene with no visible light.

For commercial program producers who need to match frames, the freeze mix function enables a previously recorded frame of video to be superimposed over a live image in the viewfinder. This way, users can adjust the camera's position to get the same framing for the next shot.

The new camcorders accept an assortment of 1/2in HD lenses available from Canon and Fujinon. The PDW-F350 and PDW-F330 camcorders also accept 2/3in lenses via an optional adaptor.

Bob Ott is vice president, optical and network systems, for Sony Electronics.