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Differences Between 8mm Tapes

Hello,

I have read with a lot of interrest your pages since i have a sony dcr-trv355e, which is equivalent to model 350 in us.

All the pages dealing with this subject quite always ignore the being of computer data8mm tapes that are really great for computers. After having seen a lot of thing on sony web site, it seems obvious that data8mm are in fact MP tapes. Could they be used inside my camcorder without risks ? Do you have some info about this ? In fact, i have already done some records on such tapes and it works fine. What worries me a little bit is the possible damage done to the camcorder itself, and especially on the heads.

In some forum, people says that those tapes will hurt my camcorder due to the usage of different lubrifiant on the tape, other says that the particules are not the same, and thus are not fitted to the camcorder ... a lot of smoke, but no real clue. I am trying to find someone having used those data8 tapes for long enough in order to be able to state the right things.

This really interrests me since I have plenty of those tapes dropped out of my company since they have switched to another way of doing computers backups. Typically, a data8mm tape of 112M will give you about 1 hour of digital video recording.

Some ideas ? some good advices ? thanks

Phil
Wed, 21 Jul 2004 04:06:15 +0200

While I can't add much to your description of the differences between types of 8 mm tapes, I went through the same kind of reasoning when I bought my Sony DCR-TRV240 camera. Mainly I wanted to be able to play my earlier analog tapes on it (standard, not Hi8) and was wondering if I could re-record them in digital. Since digital recording is quite uneffected by differences in S/N ratio I couldn't understand why Sony recommends Hi8 tapes. I have been using the standard tapes ever since and have yet to notice any deterioration, yet I have this lingering feeling, that perhaps there may be other factors involved that I am ignorant of. Of course I can't find any meaningful information either.

Bob Lantos
Tue Aug 31 18:52:48 PDT 2004

I have used 8mm datatapes from a backupsystem for computers. Before use I erased the tapes with an audiotape bulkeraser. I works perfectly. The tape specifications for databackup are very high in relation to dropouts. Therefore the tapes are very good, also for use in a camera.
Kind regards,
Lex.

Lex Goode
Mon, 14 Nov 2005 04:36:37 -0800

Being a novice in the field, i am still to learn the basics of the game, only the thing that has troubled me till now is the right media for Sony DCR-tvr285E. Concept of 8mm and Hi 8 are quiet confusing, what i am unable to understand is are there three catagories ie 8mm video 8, Hi 8 and Digital 8 or only two ie Video 8 and Hi 8. Morover there is tendency among the dealers to push video 8 when you ask for Digital 8.(This happened with me in Panchkula, Haryana, India)
If anyone can guide, please share which is the right media for this product. Sony should bring all of us out of this vague information.

Rojhe
Tue, 13 Jun 2006 00:35:19 -0700

Hi,

Being a audiophile ( and now a videophile ) and having a electronic
engineering background, I have learned much about magnetic properties especially concerning magnetic tape.

Magnetic tape whether it be audio, video, or digital the same specifications applies, regardless of format.

The specification called Retentivety OR Remanence as it is sometimes called is a measure of how much of an applied magnetic field “remains” after that magnetic field has been removed. This spec is measured in gauss. A gauss is a unit of measuring magnetic flux density or magnetic induction.

There is also another specification called coercivity that you did not mention in your article. It is as importance and retentivety or remanence . Coercivity is a measure of the level of demagnetizing force that would need to be applied to a tape or magnetic particle to reduce the remanent magnetization to zero. In other words erase the tape. This spec is measured in Oersteds. An oersted is a unit of magnetic field strength. Usually the magnetic field produced at the center of a solenoid or coil. A.k.a record and erase heads.

Typically ferric oxide, the very low grade tapes have Coercivity, Retentivety or Remanence specs that are low. High grade tapes or high bias are usually ferric oxide treated or modified with cobalt or pure metal ( not oxide ) particles that alter the original megetic characteristics of the ferric oxide giving it higher magnetic properties and higher Coercivity, Retentivety or Remanence specs. Years ago Chromium Dioxide was the first high bias tape. It was not ferric oxide.

Metal tapes, and there variations have the highest Coercivity, Retentivety or Remanence specs of all magnetic tapes, mainly because the metal particle are pure metal particle, not oxide or a rust. Plus the metal particle are much smaller than their oxide cousins allowing much tighter and greater packing densities thus inceasing Coercivity, Retentivety or Remanence specs even more.
There are variation in this class of tapes as technology has progressed so has the methodology of packing the metal particle on the tape substrate.

Metal particle tapes are jus that metal particles, however the metal particles are encapsulated in a coating to prevent them from oxidizing and therefore “rusting”.
Evaporated metal tapes, are made differently, the start out with metal particle then plasma flash it, it them turns to vapor and sticks to the tape binder. This packs much more metal on the tape per given area thereby increasing density. This is why these type of tapes are the most expensive and have the highest magnetic ratings of any tape available.

Typically high grade or high bias have Retentivety numbers in the 1400 to 1800 gauss range. Metal particle tapes have nearly twice that amount at about 2000 to 3600 gauss.
Evaporated metal tapes have the highest magnetic specifications of all magnetic tapes, usually with Retentivety numbers in the 2800 to 4000 range. All of the above mentioned also will have increasingly higher Coercivity specs as well.

You also have a substrate usually polyester and a binder which holds the oxide or metal particle onto the polyester.

I usually look for the highest Coercivity, Retentivety or Remanence specs per a given tape type. You want the noise specs to be the lowest possible -55 for example and the sensitivity and output to be a positive number and be as high as possible. Its very hard to find specs today, seems like companies are guarding them against there competitors.

The bottom line, you could use regular Hi8 tapes for Digital camcorder recording, however I would think the metal evaporated tapes with their higher density and higher base magnetic properties will deliver better picture quality and longer shelf life.

Keep in mind in the digital world you are not recording analog any longer. And the amount of digital information stored on a tape in a digital camcorder is incredible. So why not spend a few extra bucks and make sure you have the proper media to absorb all that data that’s stored on a digital video tape.

Hope this clarified and helped.

Dave Blaker

Dave blaker
Fri, 30 Jun 2006 12:27:29 -0700

I am a BBC engineer and have a Sony DCR-TRV250E. You are correct that the picture quality of D8 is independent of the tape used or the SP-LP mode used - the bitstream is the same in all cases. All that changes is the robustness of the signal - the ability to recover those bits recorded.

I have been using Video8 (MP) tapes for three years without incident, and recently had video dropout problems, when using Fuji MP tape for the first time. I switched to Sony Hi-8 HMP tape to find the problem persisted. Tests on my usual Sony and TDK video8 MP tapes returned good video, although only in SP mode.

I have cleaned the heads, although they are obviously becoming worn. I was very surprised therefore that with the camera in a marginal state I should be getting BETTER results with video8 tape than with Hi8. I suspect the Fuji video8 tape formulation is closer to Hi8 than the Sony or TDK ones.

Perhaps the tape characteristics of video8 MP are better suited to digital recording - that would seem to tally with the above post stating that 8mm data tapes are MP.

I have found nothing definitive to suggest that Hi8 tape is better suited to D8 recordings - only vague recommendations. I can only wonder that perhaps the margins on Hi8 tapes are better for the manufacturers? I would definitely recommend you make tests with your own camera before committing valuable recordings to any particular tape format.

As an aside I have heard an interesting rumour that DV was originally developed on the 8mm format - other manufacturers objected to the advantage that Sony would have with their existing 8mm formats, and so the miniDV 6mm format was developed. With their less exacting physical tolerances I have found D8 cameras to be generally more robust than miniDV.

H Johnson
Sun, 24 Sep 2006 23:59:18 -0700

I'm new to Digital8, and have the same frustration about deciding on the best value for blank tapes. I found some detail specs on one of the Sony Digital8 tapes here:

SONY 60-MINUTE DIGITAL 8 TAPE

They have a good price, too ($3.38 each).

It would be nice to find this level of data on all the Sony tapes.

John Hime
Tue, 13 Feb 2007 16:06:22 -0800

The best quality tapes i've seen are the Sony Hi8. And all 8mm are the same, but when placed in a Digital camera they actually act as a hard drive, the video is not recorded but saved. Its kinda like the tape drive on the KilikoVision

coricaman
Sun, 18 Feb 2007 19:25:54 -0800

It would seem tape needed depends on camera. If you have a Digital8 camera, you should probably use the tape designed for it, since it is the first DV format. See also Wikipedia regarding 8m formats. Here is a quote: "Hi8
To counter the introduction of the Super-VHS format, Sony introduced Video Hi8 (short for high-band Video8.) Like SVHS, Hi8 used improved recorder electronics and media-formulation to increase picture detail. In both systems, a higher-grade videotape and recording-heads allowed the placement of the luminance-carrier at a higher frequency, thereby increasing luminance bandwidth. Both Hi8 and SVHS were officially rated at a luminance resolution of 420 horizontal TV/lines (566x480 in today's digital terms), a vast improvement from their respective base-formats of 240 lines and roughly equal to laserdisc quality. Chroma resolution for both remained unchanged at approximately 50 TV/lines. All Hi8 equipment supported recording and playback of both Hi8 and legacy Video8 recordings. Video8 equipment cannot play Hi8 recordings.

By this stage, Betamax's share of both home and camcorder markets had declined seriously. As a result, the next-generation version known as ED-Beta ("Extended Definition") failed to take off despite its technical superiority.

The analog audio systems remained as before; HiFi Stereo outperformed Video8/Hi8 AFM in theory, if not practice, but remained restricted to high-end machines.

In the late 1980s, digital (PCM) audio was introduced into some higher grade models of Hi8 (and SVHS) equipment. Hi8 PCM audio used 12-bit samples with a sampling rate of roughly 32 kHz, which was far short of CD quality. PCM-capable Hi8 and SVHS recorders could simultaneously record PCM stereo in addition to the legacy (analog AFM) stereo audiotracks.

The final upgrade to the Video8 format came in 1998, when Sony introduced XR capability (extended resolution). Video8-XR and Hi8-XR offered a modest 10% improvement in luminance detail. XR recordings were fully playable on older non-XR equipment, though without the benefits of XR.

[edit] Digital8
See also the complete article at Digital8
Introduced in 1999, Digital8 is digital video recorded on Hi8 media using the industry standard DV codec. In engineering terms, Digital8 and miniDV are indistinguishable at the logical format level. Digital8 uses the same cassettes as Video8, but otherwise bears no resemblance to the Video8 analog video system. Some Digital8 equipment can play (not record) Hi8/Video8 recordings, but this is not a standard feature of Digital8 technology. To store the digitally-encoded audio/video on a standard Video8 cassette, the tape must be run at double the Hi8 speed. Thus a 120 minute Hi8 tape yields 60 minutes of Digital8 video. Most Digital8 units offer an 'LP' mode, which increases recording time on a T-120 tape to 120/2 * 1.5 == 90 minutes.

Sony has licensed Digital8 technology to at least 1 other firm (Hitachi) who marketed a few models for a while, but presently, only Sony sells Digital8 consumer equipment.

Hitachi Digital8 CamcorderDigital8's main rival is the consumer miniDV format, which uses narrower tape and a correspondingly smaller cassette shell. Since both technologies share the same logical audio/video format, Digital8 can theoretically equal miniDV in A/V performance. But as of 2005, Digital8 has been relegated to the entry-level camcorder market, where price and not performance is the driving factor. Meanwhile, miniDV is the de facto standard of the digital camcorder market, with DVD recordable camcorders also increasing in popularity due to the ability to take the media from the camcorder straight to a standard DVD player."

If nothing else, capacity of Hi8 will be 1/2 listed capacity. You alway get better signal on slowest play possible, not extended or LP. or so it would seem. Why take chances? What value do you put on your recorded memories? A few bucks seems worth it.

bob miller
Mon, 20 Aug 2007 17:48:32 +0000

A few points:

1. Mini DV & Digital 8 are essentially the same format. The video & audio specifications are identical. Video quality is the same for SP and LP recording, but audio quality will reduce (but not noticeably). Overall, the quality is pretty damn good, and many TV programmes and several movies have been filmed using this. Newer machines featuring MPEG compression to squeeze the data are not as good. Remember that there are 10+ GB of data on a dv tape, (more than 2 DVDs worth).

2. You may be aware of the Sony image sensor problem which affects many other brands (JVC, Nikon, etc). These brands had all been claiming their sensor thechnology was better than the competition when in fact they were the same. This is also true for tapes. Bulk produced tape (by Ridata?) is packaged & sold by Sony, Fuji, etc. I am not sure how many real 'grades' of tape there are. The cheapest I could get here in the UK were branded as Dysan. These have worked well for me in a variety of machines.

3. All tapes 'work'. It seems to me that in real life use there are too many variables (humidity, temperature, dust, static charges etc) when using and storing the tapes to be able to blame glitches specifically on the brand / grade of tape. Humidity & moving from inside to outside shooting has certainly caused me most tape problems.

4. Given that all tapes 'work', we should also consider head wear etc. This is also hard to quantify because of the same variables as above, and almost impossible to find information about. I remember well the premature VHS head falures until they got the right replacement for Whale oil lubricant in tapes. Does anyone have data for this aspect of DV tape?

Terry Gee
Sun, 16 Sep 2007 12:27:06 +0000

I've always used Video8 tapes( as cheap as $1.20 for Sony) for Digital8 recording, with no problems with dropout. Sony do say, however, that the tracking has to be spot-on for this, and that if you try to play back on a different Digital8 camcorder you are more likely to get dropout than if you were using a Hi8/Digital8 tape.
You can use Video8 tapes to record at the Hi8 format, on an analogue Hi8 camcorder, by drilling out the middle hole above the 'save' tab. With the metal Video8 tapes I can see loss of quality.

Dave Williamson
Thu, 01 Nov 2007 22:32:16 +0000

EDIT: Should read " no loss of quality"!

Dave Williamson
Thu, 01 Nov 2007 22:34:24 +0000

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