Videokarma.org TV - Video - Vintage Television & Radio Forums

Videokarma.org TV - Video - Vintage Television & Radio Forums (http://www.videokarma.org/index.php)
-   Recorded Video (http://www.videokarma.org/forumdisplay.php?f=173)
-   -   Dv / dvcpro / dvcam (http://www.videokarma.org/showthread.php?t=276706)

DVtyro 07-05-2024 05:49 PM

Dv / dvcpro / dvcam
 
Does anyone know, is there a cassette identical to one of the DV types that is/was used as a digital tape storage? Like, D8 (Data8) were the same as regular 8-mm video cassettes. I wonder whether any of DV cassettes (small, medium, large) have been used as tape storage, and if yes, have there been internal tape drives for a PC?

On the image below, the middle cassette is Data8, correct?

The cassette in the front is one of the DDS cassettes, but it seems larger than MiniDV and has different proportions.

https://upload.wikimedia.org/wikiped...e_drive_01.jpg

DVtyro 07-05-2024 06:04 PM

Right, in Exabyte's own words:

Quote:

With helical scan's growing popularity in the data storage industry, HP and Sony entered the market by introducing a new helical scan technology, DDS (digital data storage). DDS uses a 4mm metal particle tape and is based on technology originally developed for digital audio recording (DAT). This technology initially provided a capacity of 1.3 GB on a 60-meter tape.

Over the next few years, DDS continued to evolve, eventually increasing its capacity to 12 GB on a 125 meter tape (DDS-3) in 1995. As with QIC technology, DDS is most suitable for desktop backup.
So, Sony & HP took Exabyte's idea and ran with it, creating a new cartridge and leaving Exabyte in the lurch.

And no, DDS is different to a DV cassette.

ARC Tech-109 07-06-2024 03:05 AM

To offer some clarity here the Video-8 & Hi8 helical scan format was offered as a digital backup by Exabyte such as the EX-8200 and EX-8500 while HP, DEC, Silicon Graphics and SUN Microsystems embraced the DDS or Digital Data Storage format based on the established Digital Audio Tape format from the late-80 (some incorrectly assume DAT was derived from DDS). Both formats were SCSI only interface and for the most part have been replaced with optical formats however the third linear based format DLT seems to somehow survive today. There are some larger capacity Exabyte drives, Mammoth for example that were also used.

For a time Silicon Graphics offered a DDS backup drive with DAT audio firmware that would allow recording & playback in the native DAT format for use in their IRIX based MIPS workstations but they're far and few between. None of the formats are capable of direct digital video playback be it Digital-8 despite the ability to use a standard metal Hi8 tape nor can they read/play the Tascam DA88/98 type multi-track digital audio formats.
I left the IT world shortly after the Dot-Com bust so I don't know where things have gone or what tangents have evolved, there were a large number of these tape backup vaults in operation going thru miles of tape a minute but I don't know what ever happened to them. I still use the 4MM DDS format for both backup and Digital Audio Tape as the tapes are cheap and easy to find.

DVtyro 07-06-2024 11:05 AM

Gotcha:
  • DDS has the same cassette and same/similar tape as DAT
  • Data8 has the same cassette and same/similar tape as 8-mm video, but cannot record or play video.
  • No DV cassettes - mini, medium or large - have been used as data storage.
What do you make of this picture. Clearly, this is not a data storage tape transport, this is a PC-based editing suite with a DVCPRO deck integrated into a desktop PC. I've never seen these in the wild. Have Panasonic went through with this idea? I suppose if these became a reality, they potentially could be have been used as data streamers.

https://i.ibb.co/NmBWZ7r/dvcpro-ad-02-sm.jpg

ARC Tech-109 07-06-2024 01:46 PM

Panasonic used to live by the slogan "Slightly Ahead Of Our Time" but clearly they were so far behind with this one they were in another time zone. That DVCPRO drive never made it out of fantasy land, I imagine the price and immaturity of the format kept it on the drawing board in the day. Rather amusing they would show the operator holding both the large and small tapes together as if to say they will both fit, while this may have been true in concept all of the Panasonic DVCPRO decks I've used require an adapter frame for the small tapes to work in the full-size mouth similar to VHS-C. Sony on the other hand had a motor driven adjustable reel table in their DVCAM decks and dedicated gates on the loader to accept both large & small tapes.

DVtyro 07-06-2024 02:09 PM

What do you mean, "far behind"? On the contrary, I think this would be a leap forward, fusing digital video, non-linear editing, digital effects, encoding, storage and, later, uploading to the Internet. These drives could be also used as a digital storage, as a tape streamer. Something we have now with an SD-card slot.

I can see Exabyte drives on eBay, those that take 8-mm cassettes. I also see internal DDS drives. This one would be no different. I have a feeling that Sony pressed Panasonic to not pursue this, because Sony had DDS market to itself.

I don't think the operator holds two cassettes. I think he holds one medium cassette.

Electronic M 07-06-2024 04:57 PM

Yeah the operator holds one cassette....it just looks like two when not zoomed in because of misalignment of the 2 pages of magazine ad when someone scanned it.

ChrisW6ATV 07-06-2024 07:31 PM

Quote:

Originally Posted by DVtyro (Post 3258081)
Does anyone know, is there a cassette identical to one of the DV types that is/was used as a digital tape storage?

I never saw any professional DV-cassette-related data-storage devices, but in the 2001-2004 range, some effort was put in to using Mini DV camcorders as data recorders/players for over-the-air HDTV signals, specifically from the PCI HDTV tuner boards that were available from several companies in the 2000-2005 or later period.

I had (and still have) one of the first fifty of those HDTV tuner/recorder boards, a HiPix DTV-200. At that time, hard disk drives were still expensive enough to make tape-based mass storage a cheaper option potentially, with full ATSC HD stream captures being near 9 gigabytes per hour.

AVS Forum was the big center of all things HD-related in that era, but I do not know if they have archives going back that far. Now you have me curious, maybe I will look this up for nostalgia's sake.

ARC Tech-109 07-06-2024 10:49 PM

I'd be interested as well. I was still with the training dept at this time and much of my work was centered around video productions be it instructional or talking heads in the bored room and DV was gaining ground in this arena. I was entrenched in BetaSP and just starting to make the transition to DigiBeta as it was far more key friendly so we never really embraced the DV be it DVCAM or DVCPRO but there was some Sony DSR field equipment floating around. Vendors would often provide their product promos on DV be it the professional and semi-pro and it all merged well in the final product if everything was kept digital either by SDI or 1394. I can't say the DV format machines were very robust or reliable and none of them had their lids screwed down should a tape need to be retrieved.

I don't know how well something like an internal DVCPRO tape drive would do in the real world, there were some rather crude attempts by Matrox and others to make video capture cards that were rather high priced for the prosumer market, add the price of a feeder deck and this concept starts to look really good especially for the digital desktop user who doesn't do the sheer volume of the big production houses. A simple internal peripheral that could be installed by a layperson under say Windows NT-4 or later 2000 in the day I think would have done quite well especially if it had native small DV tape support built in for the Handycam crowd. I remember some early resistance to digital by the big broadcast boys when it included the word compression but they did after all make DigiBeta one of the most successful digital formats to date and that uses a very mild DCT and 4-2-2 sub-sample, that being said there was some limited use of DVCAM for ENG during the early days and the format has since evolved into the HD world as DVCPRO-HD. I have a Panasonic AJ-HD150 editor deck with the UDC150 conversion board that does 1080i but can't say it's the most reliable but it does an excellent job of upconverting SD to HD in real time, conceptually the internal DVCAM drive could have evolved with the technology but it's unknown how that would have affected the sales of the stand-alone machines. Panasonic has always had some oddball & off-the-wall ideas floating around their world and being a fan of the Matsushita branded products I can't say they all made sense. I look at the MII format and scratch my head.
At this point it's all solid state storage and the tape formats are nothing more than relics for us lunatics who can't seem to let go of the good ol' days. To quote ChrisW6ATV tagline: "Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." I wonder what they would say about tape deck collecting, I have Type-C in my living room.

ChrisW6ATV: If you don't have any luck going back into the AVS forum archives let me know, I'm on the administrative side of OneFora the host of the forum and might be able to dig deeper.

DVtyro 07-07-2024 06:11 PM

Quote:

Originally Posted by ARC Tech-109 (Post 3258102)
I was entrenched in BetaSP and just starting to make the transition to DigiBeta as it was far more key friendly so we never really embraced the DV be it DVCAM or DVCPRO

DVCPRO50 is 4:2:2.

ARC Tech-109 07-07-2024 09:13 PM

Yes and that's at 50Mb/s and that came in around 1997 or so while DVCPRO-100 is 100Mb/s and that followed shortly thereafter. We didn't do much with the DVCPRO or DVCAM formats being already committed to the Betacam based formats and while there was some discussion about a transition it was quietly dropped because we didn't want to get locked into an incompatibility with our existing tape library.

Digital Betacam runs a 90Mb/s 10-bit Y-U-V at 4:2:2 whereas the DVCAM variants are all 8-bit depth across the format. Big difference in the grayscale. The 4:1:1 didn't play well with the chroma key and even the later 4:2:2 still had fringing issues as our suppliers didn't always take this into account when they gave us the raw talent footage to super so oftentimes we had to improvise. Everything on our end was training & promotional oriented so we needed to make everything look as polished as possible, the big-wigs wanted to maintain a top-notch image so we got the top-notch equipment and the transition to DigiBeta included a Sony DVW-970 for me and the other photographer... spending $250k was nothing when it came to selling a new product with a polished video presentation.

DVtyro 07-07-2024 11:47 PM

Quote:

Originally Posted by ARC Tech-109 (Post 3258117)
Digital Betacam runs a 90Mb/s 10-bit Y-U-V at 4:2:2 whereas the DVCAM variants are all 8-bit depth across the format. Big difference in the grayscale. The 4:1:1 didn't play well with the chroma key and even the later 4:2:2 still had fringing issues

BBC has shot several TV series on DVCPRO50, like "Space Race" for example. But they pointed out that they wanted "gritty" looking footage, so I guess 8 bits were ok.

Quote:

Originally Posted by ARC Tech-109 (Post 3258117)
the big-wigs wanted to maintain a top-notch image so we got the top-notch equipment and the transition to DigiBeta included a Sony DVW-970 for me and the other photographer.

24p, multiple knee-points/slopes, skin tone detail, soft focus, 3CCD with global shutter. It probably could do something like this :)

DVtyro 07-08-2024 12:30 AM

Panasonic's idea of an editing station: a Windows NT machine with a couple of Xeon CPUs.

https://i.ibb.co/T0bfWcg/Newsbyte50-sm.jpg

ARC Tech-109 07-08-2024 02:52 AM

I'm going to break this up so you can easily quote me, you do have a talent for this.

DigiBeta was and still is a very good format for artistic creation and that video proves this. It upscales well and retains that "edge" without looking "crusty". I worked with the DVW-970WS which is a dual aspect ratio camera with a mad DSP that can do most anything but wash your socks. I did some creative promos doing fast cuts at odd angles and they turned out great but the marketing people said they were too "urban" (whatever that was) and distracting and nixed them in favor of some stupid talking head over a powerpoint presentation... I'm not sure I can post them on Youtube being they were company property, too many lawyers with no sense of humor.

That Panasonic conceptual workstation would have been a welcome addition over what I was working with at the time, a long length desktop with monitors, decks and other support equipment all stacked and arranged haphazard as they wouldn't spring for proper racks and switchers so everything was kept "accessible" for cable swapping. I'm working for a worldwide communications company with billions in annual profits and the green light to spend half a million on A/V yet they want everything on a desktop?! okay enough of my btichin'

The hear & now. At the moment I do have some DVCAM and DVCPRO in my mix along with Digi & Analog Betacam plus the giant Type-C formats in what is my living room... I give studio apartment a literal meaning. Everything in my racks is from the broadcast professional arena and I live in a balanced 600 ohm world of XLR connectors. The main monitor is a Samsung PN64F8500 Plasma from 2014 and everything else is Sony CRT based BVM monitors. DVCPRO is Panasonic AJ-SD755 and DVCPRO-HD is Panasonic AJ-HD150 editors while my Betacam is a Sony DVW-A500/1 with the BKDW505 composite interface and BKDW515 operator panel. Everything SDI is switched by a Newtek TC550 Tricaster using the SDI inputs and this is output to a Blackmagic SDI to HDMI microconverter. No I'm not the most up-to-date on the cutting edge of the 4K world but frankly I really don't care for 4K to begin with as most everyone seems to make things look so harsh & edgy at this level. What I can give you is an honest opinion on the highs & lows of the DVCAM and DVCPRO, again they're opinions of my own educated and experienced observations looking at them thru various display mediums and they also include a Panasonic TAU series 34" widescreen monitor using the HDMI input along with the Y R-Y B-Y inputs.

At first glance both the Sony and Panasonic DV formats look exactly the same because in reality they are, Sony uses a wider track and faster tape speed but the digital formats share the same roots. On the Plasma they look sharp but somewhat fake with the dithering caused by the 8-bit grayscale, the CRT based looks slightly better and stepping down to the analog inputs makes no difference here. My source for this is a Sony DXC-D55WS docked to a DSR-1 and my scenery was the 2021 Vasaloppet ski event our town hosts. Plenty of colors against a murky snow covered ground on a bright sunny day. The announcer has no idea what he's talking about.
DVCPRO-HD on the other hand has a very clean detail to the picture but again despite this the dithering is still apparent and somewhat annoying. Unfortunately I have to suffer using the downconverted SDI output for this so it's not very objective. My source material comes from a railfan friend who shoots train videos using a Panasonic AJ-HDX900 package. Compared to the standard DVCPRO this is somewhat better in that one can see the blades of grass in the background rather than a green blanket of various shades.

Digital Betacam... my favorite but I will do my best to be objective here. Yes it's SD and right on the edge of the widescreen transition but unlike DVCPRO and its variants it doesn't have the gradients or highlight crushing and it upscales to 1080p mpg4 quite well. My source material is several file drawers of DigiBeta cassettes I've accumulated over my professional career from various post production houses and broadcast friends I've made over the past 35 years I've been doing this. Pound for pound the prime copy of the Austin City Limits presentation "LCD Soundsystem" is about the best DigiBeta tape I have. Real 4-channel audio from the board (not surround mix) that really puts my audio system to the test (2x QSC ISA-300Ti amps) and the video really looks lifelike despite being 2-dimensional. No gradiations in the lighting, background or subjects it really kicks... the posterior. Okay so I'm being politically correct, this is a family-friendly venue after all. I consider this tape to be my benchmark and have tried to insure it. My speakers are a combination of Vega D9's (earthquake on demand) and reworked KLH Model-7s that routinely get the full output of the QSC amps which run on 240V.
My less popular and known DigiBeta subjects are super boring overpaid idiots corporate somehow mislabeled "talent" talking about new products, boredroom meetings (spelling says it all) and various interviews done on site and in the moment. Comparing these with some of the accumulated DVCAM tapes received from others the DigiBeta still looks far better regardless of how ugly some of these suits are. I'm retired now so I can say this with immunity but the lawyers won't let me divulge the company names or trademarks, I will keep the peace... for now.
One thing the DigiBeta deck does well is cross convert analog BetaSP to digital including the AFM audio. I won't get into the specifics here but I will say the analog tapes look really good overall. My source material is three file cabinet drawers of interviews and raw takes I did as a camera for hire for a very well known drug & alcohol rehab that spans 20-some years. I still have my first 3/4 U-Matics. I will say the digital converted BetaSP tapes look the most "lifelike" in terms of color and quality. A word that best describes this is photographic in the sense of an old school print from a 35MM film.

Now I know this thread is about the DVCPRO & DVCAM formats and if they had a parallel with computer storage backup, the reality is they're nothing more than a proprietary digital storage medium that was used for digital audio & video recording. A container really that could have been used as a data backup medium but never was, maybe there wasn't a need for this or the parent corporations didn't want a crossover. There were a number of storage backup formats already in play at the time so it's hard for me to speculate as to why the larger formats were never used. The technology was already there and proven in the case of the Data-8 used by Exabyte and 4MM DDS, these did evolve and expand in capacity over the years with the various compression algorithms. In reality it's so hard to speculate but it sure is fun.

DVtyro 07-09-2024 12:39 AM

Quote:

Originally Posted by ARC Tech-109 (Post 3258123)
DigiBeta was and still is a very good format for artistic creation and that video proves this. ... That Panasonic conceptual workstation would have been a welcome addition over what I was working with at the time

DV, with its lower bitrate and built-in Firewire that did not require re-encoding, pushed videomaking from fussing with tape machines to pressing buttons on a computer keyboard. By the end of the 1990s it finally became possible to ingest a complete 1-hour DV tape and store it on an HDD without recompressing.

Quote:

Originally Posted by ARC Tech-109 (Post 3258123)
At first glance both the Sony and Panasonic DV formats look exactly the same because in reality they are, Sony uses a wider track and faster tape speed but the digital formats share the same roots.

Baseline DV has 10 μm pitch, DVCAM has 15 μm pitch, DVCPRO has 18 μm pitch.

Quote:

Originally Posted by ARC Tech-109 (Post 3258123)
On the Plasma they look sharp but somewhat fake with the dithering caused by the 8-bit grayscale

Depends on the display as well, how well it converts those 8-bit values into 10, 12 or 14 bits. So many tricks were employed to make 8-bit video look better, custom gamma curves, HDR processing, etc.

Quote:

Originally Posted by ARC Tech-109 (Post 3258123)
The technology was already there and proven in the case of the Data-8 used by Exabyte and 4MM DDS, these did evolve and expand in capacity over the years with the various compression algorithms. In reality it's so hard to speculate but it sure is fun.

Yeah, I was wondering whether Sony pressed Panasonic not to turn these internal transports into a data streamer. I guess we'll never know.


All times are GMT -5. The time now is 02:26 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.