XDCAM Technical Info FAQ


Does 25 Mbps XDCAM HD recording use the same compression as HDV 1080i recording?

Yes. While XDCAM HD recording at 18 and 35 Mbps uses variable bitrate technology, the 25 Mbps alternative uses a fixed bitrate for compatibility with HDV 1080i editors and recorders. Basically the only difference is that HDV editors use Transport Stream (TS) and XDCAM HD uses Elementary Stream (ES). When the PDW-F70 recorder and the PDW-F30 player are fitted with the optional PDBK-102 MPEG Transport Stream (TS) card, these decks can be connected directly to HDV 1080i recorders, camcorders and compatible NLEs, via FireWire.

Why did Sony choose bitrates of 18, 25 and 35 Mbps?

Because MPEG2 includes both interframe and intraframe compression technology, it can offer higher quality at lower bitrates than intraframe compression alone. The XDCAM HD system uses 18 Mbps and 35 Mbps variable bitrates, plus a 25 Mbps constant bitrate. These rates offer decisive advantages in cost, recording time and compatibility. For example, the XDCAM HD system offers the longest recording time currently available in an HD camcorder: over 120 minutes at 18 Mbps. And thanks to the low bitrates, XDCAM HD recording is compatible with just about any NLE that works with 25 Mbps.

What is MPEG long GOP?

Like HDV recording before it, the XDCAM HD system uses the international standard MPEG 2 Main Profile at High Level encoding with a long Group of Pictures (GOP). Because the system combines interframe and intraframe compression technology, it enables us to achieve a higher picture quality at lower bitrates than systems that use intraframe compression alone. As we've just stated, XDCAM HD production is compatible with NLEs that accept HDV signals. MPEG long GOP is the reason why.

What is the operating temperature range for XDCAM systems?

The specified operating temperature for XDCAM camcorders ranges from - 5°C (23°F) to 40°C (104°F) ambient temperature, which is a wider range than current professional tape-based camcorder products. XDCAM products operate as well as (if not better than) current VTRs and tape-based camcorders operate when used in the same environment (ex. typical cold winter weather or hot summer conditions).

What is the Professional Disc cartridge made of?

The cartridge is made of polycarbonate and the storage case is made of polypropylene.

How long does the laser last?

In the decks, Sony's recommended replacement interval for the laser is 6,000 hours of operation (recording and playback combined). This corresponds to three years of use at a constant eight hours a day, five days a week, 50 weeks a year. On the camcorders, the interval is 4,000 hours of operation. These replacement intervals are based upon Sony's simulation of normal usage. Sony optical products constantly monitor the laser's health by checking the current to the laser. As the laser approaches the end of its life, the current will fall out of tolerance, triggering an alarm. In this way, you can replace the laser before failure occurs.

Can I replace the laser myself?

It depends. The replacement item is actually an optical block that includes the laser. Replacing and adjusting the optical block requires no special skill. But the installer would require a special measurement tool called an Autocollimator. However, Sony does not expect that a customer will want to buy an Autocollimator for such infrequent servicing.

Can older XDCAM HD products be upgraded to support dual-layer media?

No. Dual layer disc technology cannot be supported by the PDW-F350 or PDW-F330 camcorders, the PDW-F70 or PDW-F30 decks. However, the PDW-F335, F355, F75 and PDW-U1 all support single-layer discs as well as dual-layer discs. Any single-layer material you record today will remain compatible with the new generation of dual-layer recorders.

I'm receiving an 04-X7 error message on my XDCAM camera. Can you tell me what this means?

The 04-X7 error code is described in the service manual as "Cannot move to disc's innermost or outermost circumference." This could mean something may have fallen into the transport and is preventing the optical block from moving back and forth along its track.