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  1. Hi folks,

    This is my debut post here, so hello to everybody!

    I have a project which involves digitizing/capturing a good number of 25-year-old Panasonic MII Metal small format (camcorder size) tapes. But we're getting some image quality issues/artifacts on the playback. I need help identifying the problem, hoping to overcome the issues and get a clean capture.

    Here is an example of the problem: https://www.youtube.com/watch?v=WaHoZXbUiWM

    It's best described as random horizontal shifting lines.

    The deck we are using is the same one that was used with these tapes 25 years ago. However, it has recently undergone a basic service in anticipation of this project (belt and servo fix, head-clean, etc.) and appears to work well, although I'm not sure if this issue is deck or tape related.

    Here is the deck we are using:

    Image
    [Attachment 58573 - Click to enlarge]


    We've tried adjusting all the settings on this unit (tracking, etc.) but cannot seem to resolve the issue. The guys who are handling the digitization/transfer have another MII deck they are willing to try which is a much more advanced model (with many more bells, whistles, and knobs). However, this 2nd deck has been hard-modified to accept the large format MII tapes only (our small MII tapes will not go in). So, to test our small tapes on this deck is going to require switching out the spools from the smaller cassettes into larger ones. However, we'd much rather see if we can identify this issue before dismantling over 50 tapes!

    We also tried different tapes. Some are better than others, with some being almost perfect (with no issues). But most have the issue shown in the video example above. This leads me to believe it may be more tape-related? I honestly have no idea.

    I've heard this kind of issue can be related to timing, and perhaps some time base correction tools could help here?

    Anyway, any help/advice you can provide would be greatly appreciated!
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  2. Hehe you could send me a tape so i can verify, i asked some experienced guy and the answer was like "it just looks old and used, problems with the head looked different"
    The problems appear to me like moire and digital artifacts (both at the same time more or less).
    Last edited by emcodem; 28th Apr 2021 at 14:55.
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  3. Oof: that is an ugly problem, which may or may not be easy to solve. We see this with VHS sometimes: usually indicates the tape is permanently messed up, but occasionally indicates the playback deck is way out of alignment. Since your deck just recently had a tuneup, the tuneup might possibly have thrown the deck off from the exact alignment it had when it recorded these tapes 25 years ago. No way to determine if the fault is in the tapes or the deck unless you can try the tapes in an alternate deck. Since your transfer guy has access to another MII unit, it would be well worth swapping one of the problem tapes to the larger shell so it can be tested in their other MII deck. Among this newer decks "bells & whistles" might be timing correction circuits and other features that could perhaps help reduce the distortion. If you're really lucky, the distortion will disappear entirely when the tapes are played on another deck, meaning yours needs to be re-adjusted by whoever serviced it.

    There are other boxes you could try connecting between player deck and capture system to reduce the distortion, but its best to find out for sure whether they're needed. If your player is faulty, you just need to use another player or have yours re-tuned. If the tapes themselves are faulty, more involved restoration measures could be necessary. The first step toward solving this is swapping this mini MII tape into a larger shell so your transfer guy can evaluate it on his own calibrated system.
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  4. First, THANK YOU to those who replied and offered their thoughts and advice. It was certainly helpful in determining the core of the issue.

    I have some excellent news: The problem has been solved!

    We eventually arrived at the solution after quite a few steps, and for posterity I will detail the process here in its entirety in the hopes that it may help somebody else in the future.


    First MII Deck (the original) AU-W35H:

    As detailed in the post above, the first deck we tried was the one used in the original production of the tapes. Unfortunately, even after servicing, the results were abysmal (with the banding you see in the above posted video). Even after trying to make adjustments to the tracking and what we could do with the TBC, nothing worked.


    Second MII Deck - AU-66H:

    This deck had a lot more features than the previous deck, including jog/shuttle playback, head-selection, and more knobs to tweak the image output. But, as stated above, it had been modified to only accept the larger format VHS tapes (and not the small MII tapes we had). So, we took one of our MII tapes and transferred it into a VHS cassette to run it on this machine.

    The results were *better* but only slightly. There was still a lot of horizontal shifting and the image quality overall was unacceptable. So I followed the advice of Colin over at video99.co.uk (who also was kind enough to offer some great advice over email), and opened up the unit and attempted to regulate the temperature of the TBC card inside this unit. This provided another *slight* improvement. But we still were a ways off.

    Then we tried something crazy: Instead of playing back normally, we used the jog wheel to playback the footage in VAR mode (with +1) which is basically real-time playback, only in VAR mode. Amazingly, MOST of the image artifacts went away! I don't know how, but somehow the combination of regulating the temperature of the TBC card and playing back via the job in VAR mode +1 resulted in a much cleaner image.

    But there was a catch: Some shots/scenes would be almost flawless, and others were just a terrible as they were before the fix. For example: We'd have a close up of an actor and it would be super clean, then the director would reframe the shot for the next sequence and it would be a garbled mess! And this was consistent, as we could rewind back to the previous shot and it would come through clean again.

    Then I noticed the playback head switch on the unit, which enabled me to switch payback between the "play" head and the "r/p" head. Switching this one way or another cleaned up the image almost 100% with certain shots. Some scenes needed this switch to be in "play" mode, and others needed it to be in "r/p" mode. It was so odd, but it worked, and if somebody could watch the playback and switch this mode accordingly we would essentially get 100% clean playback. But this was a very complicated solution that required one (maybe two) people constantly monitoring the feed to ensure the best output. Quite unacceptable for 40+ tapes!


    Enter our third unit - The AU-65

    We ended up getting a third unit. This one came from NBC in New York, at the old studios in Rockefeller Plaza. It arrived in excellent condition, but was unfortunately also modified to only accept VHS tapes.

    So, we continued transferring MII tapes into VHS cassettes and gave them a whirl on our 3rd deck. VOILA! The image was perfect, crystal-clear right out of the gate! No switches, no fans and hairdryers, no fiddling with knobs. Perfect images!


    Conclusion: It probably all boiled down to the infamous TBC issues and deteriorating cards inside the units.

    The third deck used an analog based TBC (I believe) which had weathered the test of time much better resulting in crystal-clear playback of the tapes. I am SO glad it was not tape damage, and from what I hear in this case, it rarely is (provided you store them correctly, and we always did).

    I wanted to thank everybody here who provided advice, and hope this insight may serve to help others in the future!


    Some images of our success:

    Image
    [Attachment 58642 - Click to enlarge]


    Image
    [Attachment 58643 - Click to enlarge]
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  5. Wonderful news indeed! Very glad things worked out, and in a reasonable time frame!

    Thanks for following up and posting complete details of your partial successes and eventual solution: there aren't very many posts or threads specific to MII format, so its great you documented your experience here.

    BTW, just doing a cursory search into the MII format brought up this tale from archivists at the New York Public Library, with commentary from an NBC technician. Apparently MII was a rather problematic format when new, hasn't gotten better with age, and is among the most difficult to capture today. Very fortunate you were able to source a perfectly-maintained ex-NBC deck!
    Last edited by orsetto; 29th Apr 2021 at 17:57.
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