Pro video blog…Produced by Philip Johnston DoP/Editor

This was written by me for the IOV Focus magazine during September 1996.

There has never been a time when our industry has had so many formats from which to choose. Aside from the
analogue systems, there are now six new digital formats which have muddled the water that bit further. Philip
Johnston gives his views on the new range from Sony which echoes the feelings of many within our industry…

Sony have dropped the ‘C’ from ‘DVC’, so that’s why I will now refer to it as DV. I recently attended a Sony seminar on all of their digital formats and for those of you with money here is the line up.

1 . Digital Betacam

Top of the tree and mainly used for broadcast dramas and commercials. It has a no compromise on quality, 10 bit recording and can be switched for the 16:9 wide screen format. It also boasts four channels of uncompressed 20-bit digital audio.
Cost approx. £50K upwards and that‘s only for 1 camcorder

2. Betacam SX

This seems to be pitched at the news boys and documentary makers of the broadcast industry. Using SDDI, you can send your material two times normal speed saving time on satellite links and it records to 8 bit 4:2:2

There is a neat field editor, the DNE 50, which is an IBM notebook and a Sony SX docking station. With your DNW 7P camcorder you can download your shoot and assemble 40 minutes of compressed video and audio on a 3.5 inch magneto-optical disk. A separate 3.5 floppy disk can store your edit list and a script. It is a compact nonlinear edit system with basic cuts, very useful for a breaking news report.
Cost approx. £30K upwards, again this will only buy 1 camcorder.

3. DV Cam

Sony’s professional version of DV consumer. This is pitched at the corporate boys and educational establishments, running on 4:2:0 (as you may be aware by now, the less numbers after the 4: the less picture information.) The main features of the Pro format are higher quality than DV (Note 1), four times real time transfer to disc for editing, and a super CIipLink system (on the higher specified camcorders) which puts a thumb nail picture of all your start/stop frames onto a 16K chip in the tape. When you transfer the final production onto Sony’s E57
nonlinear edit station you have a stream of thumb nails that you can View. Better still, to save the editors time, if your presenter has four takes, you can via the camera mark NG (no good) or OK onto the thumb nail. There are four channels of 12-bit 32kHz audio or two channels of 16-bit 48kHz digital audio. Finally, DV and DVCam are compatible both ways.
Cost approx. £16K for pro camcorder.

Note 1. A regular reader David Heath wrote “One big error in that. There is absolutely NO difference in quality between DV and DVCAM. They were both 25Mbs, same raster, same compression, and same chroma subsampling (4:2:0 – not 422:0). Exactly the same bitstream. True, DVCAM usually came with a higher quality camera front end, but that should be seen as separate from the recording format.

What IS different between DV and DVCAM is that the latter has a guard band between the tracks, which allows for reliable insert tape-tape editing. If the tape is purely used for acquiring, with the data then transferred to an NLE, DVCAM offers no advantage.”

The DHB1000 DV Edit Deck

Now I have taken on through the Sony digital range of video equipment, what about the performance of the DHR 1000 digital component DV video recorder? My only complaint to date is the extortionate price of the 3 hour tapes at £50 each (When will we see the 90 minute tape, Sony?). And what can the DHR 1000 do ?…these are my seven favourite findings, not quotes from the manual.

1 Copy to 10 generations or more with NO LOSS in QUALITY. digital to digital.

2 Two stereo 12-bit PCM sound tracks or one stereo 16-bit track (CD Quality). Please note. As the VIDEO and AUDIO are sent down the same Digital lead, you cannot add mustc or a voice over at the same time. Therefore you need to use the 12bit option to give you a free sound track to edit onto. You can balance the sound when making a copy onto VHS.

3 Re-use DV tape stock. There are 60 minute and 180 minute large tapes for the edit recorder, although the edit
recorder can also take the smaller tapes without an adapter. I have gone 6 passes already with only one artefact showing up. If the tape head does not record properly is. a bit of dust etc., you get a two-frame pixilation effect across the entire picture. You must edit this out during the edit but, 4 frames per 80 minutes with no drop out iS
pretty dammed good in my books.

4 Spool through your 60 minute camcorder tape and, using the edit window, you mark ten ‘ins’ and ten ‘outs’. This shows you a colour thumb nail picture of the first and last frames chosen. The edit window is available in ASSEMBLE mode only. Press START and go and make a cup of tea as the recorder assembles your wedding for
you! Please note. You must make sure your editor and source machine are both switched to TIME CODE before pressing the ASSEMBLE button which activates the edit window.

5 The client wants to see the first cut and make changes. Fine, press the DISPLAY button and it burns in your TIME CODE numbers, allowing the client to identity the correct footage. Then you can cut or add footage by doing another DIGITAL copy and adding or Subtracting footage. Remember NO LOSS IN QUALITY as long as
you stick to DV mode.
You can add effects with a Panasonic MX50 or mix live CD’s and effects by choosing L2 which is a YC (S terminal). But remember, this footage is YC quality not 4:1:1 digital and will not look as good by the 5th generation.

6 Remember those tedious end sequences – record the music on SVHS and oops! – I can hear a bit of audio drop out half way through. I can hear a bit of ‘audio drop out’ half way through the recording. You then have to set up the insert shot, with the 7 second pre-roll, every time you mix to a new shot — TIME CONSUMING or WHAT! A thing of the past with DV. Run in your 12-bit or 16-bit digital sound track then back to insert pictures. Press VIDEO button and it goes into pause mode. If you want to bring in a precise shot from the camera or other DV deck, press the START button. With no pre-roll time, I just un-pause and pause in between choosing new !
video stills and get the end sequence done in a third of the time.

7 The end result on DV tape is stunning and your VHS copy is fantastic. I now use Fuji SRG VHS tape for all wedding and corporate copies to squeeze in as much of the quality of the DV system as I can. PS. When will Fuji be producing DV tape ?

Unless you win the lottery, or can afford a £40K+ nonlinear edit system – DV or DVCAM is for you. It has the advantages of almost limitless generation, no drop out, no chroma bleeding, CD quality audio and less stress during editing. As I have already said, my only complaint is the VERY OVERPRICED £50 DV180 ME Sony tape.

I am assured this will rectify itself when we can buy the pro PDV184ME tape for £35.

author

Having been working in the video business since 1988 I have amassed a great amount of knowledge of both the kit and production values over the last 30 years.

One thought on “Back to 1996 IOV Focus Magazine talking about the Digital Dilema

  1. One big error in that. There is absolutely *NO* difference in quality between DV and DVCAM. They were both 25Mbs, same raster, same compression, and same chroma subsampling (4:2:0 – not 422:0). Exactly the same bitstream. True, DVCAM usually came with a higher quality camera front end, but that should be seen as separate from the recording format.

    What IS different between DV and DVCAM is that the latter has a guard band between the tracks, which allows for reliable insert tape-tape editing. If the tape is purely used for acquiring, with the data then transferred to an NLE, DVCAM offers no advantage.

    It’s also interesting to compare with DVCPRO, the professional equivalent from Panasonic. Same data rate, same compression, and same no of chroma samples per frame – but organised differently. For DVCPRO, there are chroma samples for every line – at the expense of only one for every 4 luminance horizontally.

    The reasoning was that Panasonic saw DVCPRO as digital “islands” in an analogue NTSC world. And with interlace, 4:1:1 was seen much better to cope with repeated analogue-digital conversion than 4:2:0. All that changed with the increased use of end to end digital techniques, and especially when the end product was a 4:2:0 DVD. (For the PAL world DV was always 4:2:0, for NTSC it was 4:1:1. Another example of the US being first, but then suffering a long term disadvantage. )

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