High Definition Videocassette Recorder of The Sony Company

By Eldar Kalmikov

Review contents:

Professional video recording: Its perspectives in Russia Video Cassette Recorders New videocassette recorders ProfessionalDV of The JVC Company Videocassette recorders of D-9 format of The JVC Company Digital videocassette recorder from Panasonic Tape videocassette recorders of DVCAM format High Definition Videocassette Recorder of The Sony Company Sony Videocassette Recorders of D-10 Format (MPEG IMX)

Today one of the leaders in production of VCR, working with material of high resolution is The Sony Company. Its equipment line of HDCAM format includes rather many models, different in functional and price parameters. And their amount is growing.

The top model for a few years already stays HDW-F500 videocassette recorder, which supports an opportunity of recording in few formats with progressive and line interlacing, including 24p and 60i. This is the most expensive and most universal facility without which the full workflow of high-definition television production, usually oriented for several markets with different standards (cinematograph and television) is hardly possible.

HDW-F500

HDW-250 portable VTR

Other models are more special and cost more less. Portable HDW-250 VCR allows working with video of 60i and 30p formats, but it doesn’t support 24p. On the basis of precursor HDW-F500 of HDW-500 model (only 60i) was created also “economy” series of high-definition television videocassette recorders. It include HDCAM HDW-2000 (25p, 50i, 60i) models, and also many format HDW-M2000 and HDW-M2100 (player), which additionally operate with all Betacam formats of standard resolution, including their analogous and digital versions.

None of named models has function of recording in formats of standard resolution. This is due to the aspiration for not to increase already high cost of the HDCAM equipment. However M2000 and M2100 models are equipped with build-in signal converter from standard resolution to high-definition television signal. Maximum recording time in HDCAM standard to corresponding cassette varies depending on scanning and is about 124 min when 60i or 155 min when 24p.

There are also some restrictions by recording of high-definition signal with progressive scanning. Full freedom in this area is represented only by HDW-F500. It can record five variants of high-definition television signals with progressive scanning (1080/23.98; 1080/24; 1080/25; 1080/29.97; 1080/30) and three variants with interlacing (1080/59.94; 1080/60; 1080/50). Special advantages are created by presence of 1080/24 mode (or 1080/23.98), as, according to ITU, it became the universal international format for material exchange (and information recorded in 1080/23.98 mode can be easily converted in 720p). In the nearest future HDCAM VCR of “economy” 2000 series have to be enriched by additional board for operation with 720p/480p signal.

Each one of named formats has its advantages and disadvantages, however it is rather useless to argue about them. Usually such arguments are provoked by the ones, who are not familiar with real production and face the problem theoretically or have some mercenary interest in promotion of one format at the expense of another. On the practice expediency of choice of format and scanning is determined only by material assignment: where and in which standard it is going to be “delivered” to the viewer: tape cinematograph, electric movie theater, one of world high-definition television or medium-definition television systems.

HDW-F500 differs by that it offers an opportunity of recording in one of existing formats and use of material for cinema production and broadcast in any system without any limitations. Interlace modes, of course, have television character. Progressive ones are appropriate for full cinema production. For example, 23.98p mode is used when the frame-accurate material correspondence to the tape is required, but also it is necessary to provide its exit as video signal of standard resolution (for TV broadcast). 24p mode is useful when frame-accurate correspondence of material to the tape is required and exit of video signal of standard resolution is not needed (i. e. it is not planned to use production on the TV). But in this case opportunity to get 60i signal (with the 3:2 pulldown) stays when using HKDV-507 board. If the end result of work has to be “master” to TV broadcast in countries when record standard is PAL (625/50), then it is necessary to work in 50i mode.

HDW-M2000

HDW-M2100

For getting signal of standard resolution directly from HDCAM VCR are used lowering transformers. For HDW-F500 these are additional boards, for HDW-2000, M2000, M2100 devices this is a part of standard integration. Transformation is done through different algorithms (by user’s choice).

As to the sound, all HDCAM devices have an opportunity to record four separate audio channels, and HDW-F500, HDW-M2000, HDW-M2100, HDW-2000 models support Dolby-E and Dolby AC-3 systems.

Dolby AC-3 correspond to the Dolby Digital 5.1 system and imply use of six sound channels, among which five programmed and one special effect channel, one which low frequency signal for sub buffer is usually written. However this system has some limitations for professional use. The problem is that this sound recording format doesn’t allow doing more than one cycle of coding/decoding. In this case editing can lead to short sound “failures”. Dolby E coding system allows avoiding this, as “shots” of sound information in it are coordinated with video shots, representing an opportunity to perform few editing cycles. Also one advantage of Dolby E is an opportunity to create “master” with eight audio channels. Physically for 5.1 tracks there is used one couple of AES/EBU audio channels. The second couple of these channels can be used for traditional sound tracks. So, in Dolby E is created a “master”, which can be edited and additionally to 5.1 there are also saved two program channels for other purposes, for example, for recording of translation or stereo track.

In conclusion, there are some more details about operation with HDCAM VCR.

For information coping from one cassette to another and chop of material to NLE station it is reasonable to use SDTI interface. This is the compressed stream, but during coping it provides saving of 100% quality of initial material and copy is absolutely identical to original. If more difficult tasks than copying and simple editing are meant (mixing, fade-in, color correction, titles superposition, etc) compressed SDTI stream has to be decoded into HD-SDI signal and given, for example, to video mixer with further reverse compression of already finished program in VCR during recording.

For editing of programs in 24p and 25p modes it is possible to use Sony BVE-9100 editing controller with corresponding option. One more BVE-700 editing controller operates in 59,94i mode, but it is assigned for Japanese high-definition television market.

High-definition television videocassette recorders of 2000 series are capable to reproduce programs recorded in 24p mode with speed change +4% (but when 24-shot temporary code). HDW-F500 and videocassette recorders of 2000 series forma an editing couple, which supports 25p mode. For editing in 24P mode two HDW-F500 are needed. However on practice such configurations are met rarely. Usually, editing and processing due to economy reasons and comfort are done on NLE stations.

To get image of standard 625/50 resolution with smallest expenses for viewing and draft editing, HDW-F500 has to be converted into mode of reproduction of 25p and turn on the mode of transfer of temporary code from 24 to 25 shots/sec. In this case 24p record can be watched using SDI output.

“D&K Corporation” represented the material