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40th Anniversary of Apollo 11 Moonwalk and the loss of data

There has been much discussion over the last few years about finding and saving original tapes of the Apollo 11 Moonwalk videos downlinked from the moon. There is also an exciting project going on to restore and digitize the Lunar Orbiter tapes from more than 40 years ago.

The Lunar Orbiter tape digitization folks have just posted a commentary that bears reading by all archivists who are holding tapes. You may link to it here. The main site is www.moonviews.com

NASA, in their press conference yesterday held at The Newseum, admitted that the original 14-track 1-inch instrumentation (IRIG) tapes that contained the slow-scan video direct from the moon were most likely recycled and reused for later missions. Apparently, over 350,000 reels of instrumentation tape were recycled by NASA over time. No one apparently thought to preserve the 45-odd reels of the original moon walk.

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Kodak Durol triacetate tape with bad vinegar syndrome

I recently received two 7-inch reels of Kodak Type 31A Triacetate tape (1250 feet, Durol Base) that smelled of vinegar even before I got the envelope open.

These tapes were badly warped due, most likely, to the vinegar-syndrome induced differential shrinkage. Other factors may have been poor winding during long-term storage (I had received them after several attempts to play them on another machine).

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Updates posted for “winding tapes for long-term storage”

There was yet another discussion about winding tapes for long term storage. This time it was on the Society of American Archivists list. While it was focused on VHS tapes, where it was decided that it was more important not to leave the tape in the middle with active content exposed, some discussions of the mechanics arose and I have added them as comments to the original post, which is available here.

Dangers of old tape recorders for playback; using the elevator head

We are currently working on some un-published tapes for a major Canadian folk artist. We have a 7.5 in/s 2-track stereo recording that was one of (if not the) first studio recording of this artist from circa 1972.

At some point, this tape was played on a 1/4-track machine that injected hum onto the left channel. Here’s what the magnetic viewer showed:

hum_overwrite_dsc_0571

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Compander-type Noise Reduction Systems

Note: This information has been incorporated into this page which contains a more in-depth discussion.

I received an urgent phone call yesterday from a man who had digitized several reels of 2″ 24-track analog recordings that he wished to re-mix.

The tapes were originally recorded in about 1978-1979 and he said that he needed them to have Dolby C noise-reduction processing applied to the files.

I did a bit of research, as that did not sound correct from an historic point of view.

Here is an approximate chronology of the major noise-reduction systems and their dates of introduction:

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End of the 3.5″ floppy disk

CNET reported yesterday that Sony will be stopping sales of its 3.5-inch floppy disk media in March 2011 in Japan. Apple stopped supplying these as standard equipment in 1998 and Dell ceased that practice in 2003.

While this medium is not widely used for audio or video, there is, I suspect, still a large amount of ancillary data kept in this format. I will look through my collection and see if there is anything else I need to capture to my servers before my drives die.  I would not entrust anything important to this format.

We stopped using these about three or four years ago, with the last holdout being school work brought home. Now, even that is done on USB keys.

Long-term stability of different batches of Ampex 456 – a guest article by Gary Galo

Here’s some info that might be useful concerning which batches of Ampex 456 are good and which have sticky shed problems.

I recently unearthed 26 brand new 10 1/2-inch reels of 456 from 8 different batches. I checked one reel from each batch by playing them back and forth at 15ips (I only played the bad reels in one direction – that was enough!). The following batches were bad:

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IASA TC04 Guidelines on the Production and Preservation of Digital Audio Objects available online.

The International Association of Sound and Audiovisual Archives (IASA) has released their landmark Guidelines on the Production and Preservation of Digital Audio Objects as a free web (HTML) edition, available here.

I provided some information for the listing of tape equalizations, and I find the compiled table (here) most useful.

Thanks to Kevin Bradley and the IASA team for their work in making this available. If you want a PDF copy, join IASA and it’s available.

Cassette equalization redo

There has been much discussion on some web fora about the differences between different brands’ cassette equalization standards.

As I stated here in 2006, there is a 4 dB ambiguity at 16 kHz.

Many things conspire to make this 4 dB ambiguity essentially meaningless in a generally low-fi medium. The only reason I’m mentioning this now is that I’ve been bombarded with email from more than one participant in this discussion and apparently there may be some editorial judgment attached to what is posted.

Jay McKnight has graciously permitted my posting of his comments to me:

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Speed variation with unmatched reels

I received an interesting question from a European tape user with whom I frequently correspond:

“Is there any speed variation when playing a tape with different hubs on the supply reel and take-up reel?”

And I replied:

You raise an interesting question. The easiest answer to this is simple:
There is a risk of speed variations throughout the reel if the tape tension varies throughout the reel.
followed by the corollary:
This effect is made worse if the condition of the capstan / pinch-roller system is degraded.
and
Some capstan / pinch-roller / constant-torque systems handle this better than others.

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Watch those insects!

OK, this is not directly related to audio, but three audio people I know have been bitten by insects this spring and have suffered greatly for it. One was bitten by a spider in California, one almost died from a flea bite in Texas, and another received a suspected spider bite in Pennsylvania…so be careful…you never know where nasty insects might be hiding…maybe even under a tape box!

If you are worried about what to do, a friend, though a staunch vegan, squashes spiders. Of course, certain spiders are good and eat other insects, so this is just another one of those tough decisions in life.

And then there is mold. A good friend’s life was cut short by interaction with mold, though he was a smoker much of his life, so I’m certain that contributed to it.

As my Dad used to say, “you don’t get out of this life alive”, but he made a good run for it, living until age 93!

Playing full-track mono tapes

About ten years ago, when I transferred the oldest tapes in the United States as part of the Mullin-Palmer collection, my good friend Don Ososke pressured me to use a full-track head for the project. I had started transferring these full-track tapes with a Woelke NAB stereo (two 80 mil (2 mm) tracks) head and recording both channels. When I obtained a Nortronics full-track head, the difference was night-and-day. The full-track reproduction sounded fuller, smoother, and quieter. There were no tracking problems to speak of that would cause azimuth wander large enough to create a “flanging” or “phasing” effect of in-and-out high-frequency loss.

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Source for D5 (Decamethylcyclopentasiloxane)

I have recently been looking to replenish my supply of D5 (Decamethylcyclopentasiloxane) and did not have much luck receiving replies to my email. Others have reported difficulty finding this in quantities smaller than a 55-gallon drum.

I found a promising listing for cyclopentasiloxane and when I queried the supplier, he indicated that the analysis was 97.5% decamethylcyclopentasiloxane and the balance being octomethylcyclopentasiloxane. I suspect that is more than good enough for tape work.

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Playing a squealing reel of Sony PR-150 tape using D5 (Decamethylcyclopentasiloxane)

Today I worked on a batch of five Sony PR-150 7-inch reels recorded at 3.75 in/s in one direction, two-track mono. One of the five reels showed marked shedding during fast-wind/rewind (to get the original reel as takeup and to check the tape pack). Four of the five reels played fine. This one squealed horribly. I ran the tape up and back over the dispenser and then fixed it in position for running the tape over it during the playback session. Once again, D5, Decamethylcyclopentasiloxane, CAS Number 541-02-6 comes to the rescue. The lovely thing about D5 is that it evaporates.

APR-5003 with D5 dispenser

Is this better than cold playback? I don’t honestly know. Both work. This is easier if there is no reel machine standing by for cold playback (which there was not today). I keep a Nakamichi MR-1 in the refrigerator so it is ready to go when I need it. The Studer A810 I put in the fridge did not like it. The capstan motor seized up AND the heat output overwhelmed the refrigerator’s capacity to cool. I suspect the APR would also overwhelm the refrigerator’s capacity. Also, it is much easier to lubricate a reel than a cassette.

 

Update (2012-08) Kyread spray-on magnetic viewer fluid

In several articles on magnetic viewers, we have discussed the spray-on Kyread product.

GOOD NEWS! The company is back! I received a phone call from Ryan Blackwell this afternoon and he pointed me to their new website. The company name is now Kyros Technologies LLC.

Note their jump into the 21st century with a real website and great domain name: magneticdeveloper.com — they even have a shopping cart for online ordering. This is apparently the same product I’ve been using for the last eight years.

Agfa PEM-469 success

We had success transferring two reels of one-inch Agfa PEM-469 tape that was shedding and leaving a waxy clear-to-yellow exudate on everything. We were happy to get through these and recover the content. This is discussed in more detail towards the bottom of our Degrading Tapes page—hopefully the most up-to-date resource on the Web about problem tapes. Please let me know if you would like to help me add anything to the page. It is there for everyone struggling with old degrading tapes. If you haven’t looked already, please look at my paper on the subject.

Slide Storage Warning – Airequipt 2 x 2 Slide File

Over the years, I’ve used various methods of storing 35 mm colour transparencies. Until 1992, I used mostly metal slide boxes, but I do have about five Airequipt 2 x 2 Slide Files which are a hard plastic. One of them was sitting on a painted steel shelf and I found some oozing degradation components that were oily/greasy and rust where the paint on the shelf was scratched (probably prior to the box being placed on it).

These boxes have bubbled to the top of the priority list. The interior and slides seem to be fine…for now, and the other boxes are showing little or none of the symptoms of the one (which is probably not the oldest). The slides in this box date from 1983, but the box is almost certainly older. The Logan and Brumberger steel files are, as expected, holding up well, but I am migrating the images to hanging slide sheets from Transparent Office Products. I suspect that I’ll end up with about 2,500 sheets with probably 16 slides/sheet on average…and that will fit in seven file cabinet drawers (2′ deep). These sheets were originally sold by Franklin Distributors until Transparent took them over about half a decade ago. I bought my first sheets from them in 1991 or 1992 and they are still doing fine. Some other alleged to be archival sheets from the same time did not do as well.

We are scanning all of the images as we move them using a Nikon Coolscan 5000ED with SF-210 slide feeder.

Obsolete data formats

This is a reminder that data formats come and go just like audio and video formats. On this, the 48th anniversary of the JFK assassination, this article was posted at the Library of Congress website. It talks about first locating and then converting research data held on IBM 80-column punch cards. I remember working with those my first summer job back in 1967! I guess I have a penchant for obsolete formats, as I learned a good deal about IBM’s unit record equipment, including the amazing 407 (introduced in 1949). That certainly was not as useful as knowing about analog tape now.

The punch cards were found and converted. This is a much happier fate than that suffered by the original IRIG 14-track 1-inch tapes of the Apollo Moon Walk from 1969! In 2011, I digitized 14-track 1-inch seismic tapes surrounding the Mount St. Helens eruption in 1980, and am working on another confidential project in 2018.

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Personal Image Scanning Project

In the 2007-2008 school year, my son Robert asked me why we did not have all our family images in the computer as there were some that he needed for a report. Since this was a project I had desired to undertake for some time (but who has the time), I responded with “I’m very glad you asked, what are you doing for a summer job?”

As of September, 2012, the bulk of the work has been completed and here are the statistics:

scanning stats 2012-09-11

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Introduction

I have made a variety of static pages for my tape restoration Web site, but thought it was time to add a more user-friendly, article-based location to discuss various topics, tools, tricks, and techniques that I have come across in various ways.

What is easier to use than ready-made BLOG software, so I guess Richard is finally Blogging!

I hope you like this and find it of interest. Please let me know of any changes or topics you might like addressed.

Enjoy!

Note: This post has been put in every top-level category because it appears that a post is needed in each top-level category if the sub-categories are to be visible.

Note 2: The Tips  & Notes blog and the  Formats & Resources  static pages of this  sub-site replace the Tips and Resources static pages on the Web site. And, there is integrated searching across both the blog articles and the static pages.

Protecting the container: Heritage Building Fire Safety

While this post does not specifically pertain to audio tape restoration, it does pertain to keeping originals and copies safe, especially in heritage buildings.

This article is prompted by a devastating fire in Aurora, Ontario, Canada, where I have lived for the last 10 years and also from 1981-1983. On Friday, April 11th, there was some roofing work being done on the 135-year-old Aurora United Church. Roofers were using hot tar and allegedly some sort of open flame. Humidity is not high in the winter and we had a cold one. The church roof structure (and much of the ceiling structure of the nave) was wood. Hot tar, flame, low humidity, wind, and very dry old wood do not mix well, and the results, sadly, were predictable. The church is now a ruin. The fire department spent 4-5 hours with up to maybe 7-8 master streams running into the attic and other parts of the structure.

2014-04-12_19.01.24

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Colour repair in Photoshop and Lightroom

I was working on a media and image digitization project this spring and early summer. Some of the slides from 1960 had horrible color shifts. Here are two examples that I helped along in Photoshop and Lightroom. I did not take detailed notes on these but thought that they might provide an indication of what is possible without too much work. Obviously, other defects could have been reduced, like fingerprints, but there was an inadequate budget for this type of cleaning. Clicking on either image will bring up a larger version. I made the scans of the original slides on my Nikon Coolscan 5000ED.