Sunday, October 6, 2024

CAT-A-THON: Collective Cataloging Day

On Sunday, T.A.P.E.'s Collections Working group organized a collective cataloging day in an effort to bring together the catalogs that T.A.P.E. volunteers have been working on for the past year. So on Sunday we compiled separtate catalogs into a giant spreadsheet, labeled each tape with a barcode, and affixed a status label so we'd be able to track the status of our work. 

In two short hours, we affixed barcodes, transcribed existing barcode numbers, and affixed status stickers for 218 tapes.

Earlier this month, the T.A.P.E. Collections Working Group met to establish a plan. One of the biggest needs we identified was to organize a collective day to get tapes in our collection barcoded & ready for access. Internally, we have spreadsheets with rich metadata about our collection, and we needed to refine and combine them into something that we can easily import into our circulation library interface, Tiny Cat. The goal is for our collection to be of great artistic and entertainment use, and to extend access to rare and important material on VHS through physical and digital circulation. We have an archive in use, a collection in motion.

The first step in our collections access project was combining all of the disparate spreadsheets into one unified page. Done by T.A.P.E. volunteer and Collections lead Russell, the unified spreadsheet is a springboard for concatenating all of our collections. The reason we have separate spreadsheets is because the provenance (origin) of the tapes is different - some come from the Echo Park Film Center, the Iota Center via the Museum of Jurassic Technology, others from private collectors such as Viva Video (major video distributor in the Philippines) or even fished from the trash!

Summary powerpoint ft. cats by Franny, review of cataloging efforts led by Franny and Alohie

The next step was to assign each tape a unique identifier (UID), *usually* a string of numbers that corresponds directly to a singular physical or digital item. If you have two VHS copies of Meshes of the Afternoon (1943), one would have a UID of 00012, while the other may have been brought into the collection later and is 00300. The UID helps us distinguish between the two copies that may be similar or even identical. A UID also assists in digitization, as we can understand the intellectual link between a physical VHS tape and its digital file in the form of an MKV preservation file or an MP4 access copy. Lastly, as we gear up to rent the physical tapes in our collection, we will use the UID as a tracking system for checking items out and returning them. 

Our UIDs come as a barcode from TinyCat, our library system. A barcode is a UPC (Universal Product Code) that turns numbers into a scannable symbol. That way, we can read the UID with our eyes, but it can also be read by our extremely adorable cat-shaped barcode scanner, providing multiple modes of access into the catalog. Barcodes are not infallible - because they are on paper, the barcode is subject to damage, so multiple checks of barcodes and cataloging is critical. In fact, there are profound parallels between digital videotape (like MiniDV) and barcodes as they are both digital information encoded on physical mediums vulnerable to damage and decay.

In the collections committee, we wanted to make the collective cataloging process easier and more accessible to new volunteers. A large part of that was creating a physical label that would indicate the status of the individual tape - whether it had been cataloged, digitized, its digital record imported into TinyCat, or if the tape was good for circulation. Collections Committee Admin Lee created stickers which allow us to easily visually identify the status of each tape. The new sticker allows for greater unity in our cataloging work across many people and long periods of time. 

We also performed metadata cleanup. For tapes not cataloged, we quickly added them to the spreadsheet. Using Open Refine, we identified duplicate entries in our cataloging to remedy errors. We will continue this work of metadata clean up so ensure the best and most consistent records for internal and circulation use!  

Past volunteers have diligently worked to catalog tapes in the T.A.P.E. Collection for the past eight months. This has included manually transcribing the written descriptions on the tape and its case, which often includes rich descriptive text. Much of this work we've done in other languages, including Russian, German, Spanish, Tagalog, and more. Volunteers have also identified the format, brand, and recording mode - technical metadata that is critical for digitization. And we have also initiated a robust collections assessment to identify items in our collection that are neither circulating on physical media nor online. For tapes that are highly rare, we are beginning a process of duplication, so a non-circulating preservation tape can live with T.A.P.E., and patrons can still watch the content on a physical or digital access copy. We have also begun a process of de-accessioning, a term that means taking things that do not apply to our collection scope out of our collection. We've de-accessioned tapes for content that is freely available online to make room for future collections in urgent need of preservation. This collective effort has occurred at desk shifts at T.A.P.E. through the passion, knowledge, and skill of dozens and dozens of T.A.P.E. volunteers. 

Collective cataloging days are a remarkable process that we aim to continue. It allows us to create and refine our standards collectively, in conversation with each other. We also get to prevent the problems associated with backlogs, particularly loss of institutional memory about the collections. Our first cataloging day in March, 2024 allowed us to get a massive jump start on cataloging hundreds of tapes in our collection. 

The idea is a springboard from Sydney Kysar, whose work with collective cataloging has served as an empowering model. Syd organized a collective cataloging day with the Bob Baker Marionette Theater where they also volunteer, and led the cataloging of 500 books in their library in one day. Further, they've organized collective cataloging days with Access Books, who collaborate with school librarians to vital services that enliven school libraries, including refreshed book donations and murals (Syd is the lead mural program coordinator). After learning that school librarians work for 2-3 years to catalog their entire library, Syd organized collective cataloging days where volunteers cataloged those same books in 2-3 days. It's radical work and we are delighted to have Syd contributing to our efforts!


Our next steps in our project include

  • Drafting a collection policy on what we do & do not collection
  • Writing a collection overview document which outlines the source of our collection
  • Creating genre labels for easier identification for library circulation
  • Performing a digital audit of our hard drives
  • Uploading catalog records to TinyCat
  • Creating a preservation plan & catalog for T.A.P.E. produced items
  • Improving workflows & documentation
All of these projects are collectively driven, for ourselves, by ourselves. Our goal is to create a sustained collection that can circulate and provide artistic, entertainment, or research use. Rich metadata, no backlog!

We are SO EXCITED to keep launching additions to the Tiny Cat library for you all to explore, including renting physical tapes & viewing our digitized files. Check out our Tiny Cat Library and explore our collection here!

T.A.P.E. is a 501(c) 3 non-profit dedicated to facilitating access to analog media making, preservation, and exhibition. To support our work and access great benefits, join our patreon at just $5/month. You'll get access to exclusive rates for our rental equipment library, access to our digital and physical videotape library, and other member benefits like free workshops. 

We've launched a $6,000 goal for GoFundMe to buy essential digitization equipment to provide more archival transfer services for more tape formats. A donation will advance the work of people-oriented digitization services!

info@tapeanalog.org

Blog is written by Jackie Forsyte, T.A.P.E.'s Technical Director, and an audio-visual archivist.

Wednesday, October 2, 2024

TBC 101!

Donate today to T.A.P.E. and you'll help us dramatically expand access to digitization equipment. Preservation for the people is within reach! 

When I first entered the preservation world, one of the most intimidating yet magical words thrown around was "TBC." And it's taken me a minute to figure out what it is, what it does, and how to explain it to people. That's because explanations are often brief & technical, originating from a television broadcast world where information must move quickly. But understanding a TBC and its role as an essential building block of digitization is within reach! And by understanding this device, we can better advocate for videotape and the magic of its content.

T ime 

B ase

C orrector

TBCs are also used in glitch art!

When you are connecting more than one device in analog video playback (lets say VCR to CRT or VCR to analog / digital converter) these devices rely on synchronization to correctly display the picture and audio. And that synchronization is based on pulses sent out at regular intervals that time each device together. 

Sync Pulses & Blanking Intervals 

Think of these pulses as the machines setting their watches at the same time, with each tick of the second hand across the watches moving in sync. 

     

Encoded on a videotape are these pulses known as horizontal and vertical sync pulses that communicate the limits of the video frame. Video is made up of lines that run horizontally to construct the image. You know how a digital photo is made up of square pixels, well an analog video is made up of lines, with each line replicating how bright or dark that part of the image is. A horizontal sync pulse is a pulse that says "this line has ended, time to start the next one!" Without the horizontal sync pulse, the line would continue on forever and forever, never starting over again.

CRT Refreshing Rate

Video is also made up of two fields, a left and right one that interlace together to form one frame. A vertical sync pulse sends pulses saying "this field is ended, time to start the next one!" Without a vertical sync pulse, the frame would just keep building and never restart. 

Field Order for Analog Video

After the horizontal pulse at the end of the line, there is something called a horizontal blanking interval. The electron beam which creates the scan line from left to right must temporarily turn off so it can get back to the other side of the screen. Without the blanking interval, you'd see the beam retracing its steps from right to left. At the end of the field & frame, there is a vertical blanking interval which again is a blank image in between two frames. Without the vertical blanking interval, you'd see the beam go from the bottom to the top of the screen.
Blanking and sync pulses define the limits of the active picture, making sure it stays within the frame. These pulses are not visible. They exist at frequencies below the visual image. These synchronizing pulses power the video system, making sure that the receiver is in lockstep with the image. 

However, the devices we play videotape on and the devices we record on are not perfectly timed. And they often have issues in their mechanical functions too that maintain proper tension of the tape path. The tapes which contain the synchronizing pulses can be old, stretched, and warped. Therefore, these synchronizing pulses fall out of sync. To complete our metaphor, our watches are out of sync with each other because the gears inside start to wear down. 

As a result, a time base error occurs, whereby the picture starts to have visual errors and cannot faithfully reproduce the image. Some examples of time base errors include:

Flagging the top of the screen starts to look like a flag blowing in the wind

Skewing the bottom of the screen looks a few lines off from the rest of the image

Tearing the image looks smeared, like someone has pulled on some of the lines from one side of the screen. 

Jittering image flashes or rolls in and out of frame.

Time Base Error

You may also see a chroma noise, which looks like extra color "mist" (red and blue) that exists in the image or luma noise which looks like extra white "mist."

So, what does a TBC do?

A TBC helps support all the different components in synchronization, properly containing the lines and fields within the frame. Here, the image is "jittering" or rolling and flashing in and out of frame. This is corrected by a TBC. 


It also corrects tearing on the line level!

Tearing corrected by TBC

TBCs can powerfully correct chroma noise and clean up noisy signals. 



Light tearing and chroma noise corrected by a TBC.

One of the most important functions of a TBC is that it can prevent dropped frames. Analog to Digital Converters and their capture devices are extremely sensitive to issues in synchronization. This is different than a CRT, which is far more tolerant to these changes. If the tape or playback device falls out of sync, the capture card will drop that frame completely, leading to consistent black images or loss of consistent picture. 

It brings our playback back into synchronization and cleans up noise, providing a clearer, better picture that is a faithful reproduction of the original content. 

Processing Amplifier

TBCs also often have a built-in Processing Amplifier, a device that reprocesses the video signal so as to alter the levels of the video. 

Video is constrained by broadcast standards a set of rules set for television that creates limits for how much light, dark, and color information can be broadcast to your television. Think of it like a set of standards for broadcasts to ensure the consistent images across many, many television sets. Any information broadcast outside of these standards is cut off, meaning information is lost if broadcast outside of the levels. These standards have become a critical part of videotape.

For Luma (Y') or brightness information, we use a scale from 0 to 100 IRE. IRE is a measure of the strength of electricity or the voltage of analog video signal, derived from the Institute of Radio Engineers. Reference Black (true black) is 7.5 IRE and reference white (true white) is 100 IRE. 

Black is 0 IRE or 0% energy exerted. White is 100 IRE or 100% energy exerted. (Reference or "visible" black is technically 7.5 IRE, as signal below 7.5 IRE is for blanking).

A Processing Amplifier (Proc Amp) allows you to contain your information within 100 - 7.5 IRE. The Set Up function lifts/reduces the black point. Ideally, you want this to sit just above 7.5 IRE to faithfully represent "true black."

Here you can see my friend D lifting the set up, watch as the analog waveform monitor shows the black point going up! 

When video information goes below 7.5 IRE, it is crushing. It looks like the image has lost detail in the blacks and can appear noisy. This is what we call “artifacting,” or adding noise that wasn’t there in the original video. Information is lost and cannot be retrieved. Furthermore, your file will incorrectly represent black information. 

The Video function adjusts the spread of brightness. It certainly adjusts the upper limit of white information, but also functions like an accordion, opening and reducing the brightness spread from a flat (closed) to a dynamic/naturalistic (open) image. You want the "true white" information to sit just below 100 IRE. 

Now the video knob! Particularly watch as the very top of the waveform transforms from a very flat line (clipping) to a more nuanced, bouncing shape as they set the brightness of the video signal within broadcast range. 

When video information goes above 100 (analog waveform), it is clipping. It looks like the image is blown out/crunchy in the whites. Think of when you shine a spotlight on someone, adding a second spotlight only washes the person out and reduces fine information. Furthermore, your file will incorrectly represent white information.

Here is clipping on an audio signal. The information is cut off, turned into a flat line, which means it is lost

We also use the proc amp to adjust the chroma and hue of the video. Chroma is the strength or saturation of the color information. There are limits to how much color you can display, similar to brightness/darkness. Any information that is outside of the legal color space, or defined limits of color, will appear dramatically oversaturated and that information will be lost. 

Hue is the "direction" of or calibration to the color standards. We calibrate colors to industry standards, known as color bars. However, for home movies, where there are no color bars on the tape to use as reference, we use our eyes to correctly set hue, ensuring naturalistic skin tones and common reference points (blue sky, green grass, or red sweater) to display natural color. 

We use a a vectorscope as reference for the Chroma (saturation) and Hue (direction) of color, meant to calibrate SMPTE color bars to the correct broadcast standards. The points on the graph should match the squares with the corresponding color. 


SMPTE Standard Color Bars for Analog Video, Allowing you to calibrate color hue and saturation

Each of the points of the star-like shape should align with the points, seen on the little square boxes at the tips of the shape.
A vectorscope displaying the color bars

R = Red

Mg = Magenta
B = Blue
Cy = Cyan
G - Green
Yl = Yellow


All of these parts of the processing amplifier are critical for ensuring high-quality transfers. In terms of the visual image, we want to make sure that home movies look how they should. They are imbued with such potent power and memory, we want them to evoke that sense memory of the event, particularly with skin color. For signal information, we want to preserve all information encoded on the tape. 

Without a processing amplifier, information will be lost at the upper and lower ranges of color and brightness, as it cannot be contained within broadcast standards. While this may not always read to our eyes, this is important for long-term preservation. Digital files made during digitization will be the new items passed on generationally or among people today. Making sure they set up to be the most faithful to the original is key to the valuation of these home movies and their preservation.


TBC Obsolescence 

Many professional decks have built-in TBCs and processing amplifiers. This means you can playback analog tape and perform these vital corrections all in one swoop. 


However, professional decks don't support all recording styles. Of highest concern for us at T.A.P.E. is the lack of support for Extended Play (EP) and LP (Long Play) modes. These recording styles were designed to encode x2, x3, x4 as much information on a regular tape by encoding the information closer together. Improving the affordability of videotape, EP and LP modes often have hours extra of footage in home recordings. 


These tapes will not play back in professional decks, which were not designed to support EP/LP recording or playback. Meaning, we cannot use them to digitize these home videos. Instead, we need an external TBC, or a device that is added to the signal flow of a consumer deck that does support EP/LP to stabilize and improve the quality of the signal. Without a TBC, an EP/LP signal coming out of a consumer deck is too unstable to be digitized, leading to information dropping out completely!


External TBCs are often hundreds, if not in the thousands, of dollars. They contain complex electronic circuitry and often die. They are in high demand and can often go to the person who has sustained commercial or other financial backing. This leaves most people and organizations stuck!


Hardware obsolescence is grim prospect. But by using crowd-funding to purchase our own TBC, we aim to provide wide access to our low-cost digitization services to the Los Angeles public. With the generous donations to our Go Fund Me this past week (!!!!) we are now able to purchase this critical piece of hardware, and dramatically expand our services.


Thank you so much to our donors. What a heartwarming and remarkable contribution. We are honored that you are part of this work.

Let's do more of it!


T.A.P.E. is a 501(c) 3 non-profit dedicated to facilitating access to analog media making, preservation, and exhibition. To support our work and access great benefits, join our patreon at just $5/month. You'll get access to exclusive rates for our rental equipment library, access to our digital and physical videotape library, and other member benefits like free workshops. 

We've launched a $6,000 goal for GoFundMe to buy essential digitization equipment to provide more archival transfer services for more tape formats. A donation will advance the work of people-oriented digitization services!

info@tapeanalog.org

Blog is written by Jackie Forsyte, T.A.P.E.'s Technical Director, and an audio-visual archivist. 

Wednesday, September 25, 2024

Mold Cleaning Before Transferring Nancy Lomeli's VHS

 In the preservation world of magnetic tape media, mold is an enemy. It is a hard stop in the process to digitize one's media. This means, if it is identified, the tape must not be played before being cleaned. For many for-profit digitizing companies, this means handing back the tape to their customers while letting them know there is nothing they can do about it because they don't offer mold cleaning services.

T.A.P.E. has been interested in making sure we never have to have that conversation with our patrons. We are consistently impressed with how intact the media is underneath the mold after a cleaning. In this post we're going to discuss the cleaning process used to digitize Nancy Lomeli's birthday party, documented in 1996 in Jalisco, MX at her grandfather's ranch Santa Martha, that is now a historical landmark.

 
Footage of mold-cleaned VHS, courtesy of Nancy Lomeli

We've recently acquired a cleaner specifically for mold cleaning tapes, donated by our volunteer Jason Flood. But we'll get into how this specific cleaning was done by hand and why. 

3D Printed Tape Cleaner

Why does mold grow on tape-based media? We're working on a more technical post about these questions, but for now let's talk about the basics. Magnetic tape media loves a dry, relatively cool and stable environment. Unlike film, the coldest temperatures are not required for healthy tape storage - a stable neutral temperature that is on the cool side is ideal - and humidity levels might be the more important factor for tape storage. 

In an environment that is both fluctuating in temperature and humidity, not only will the quality of tape playback be affected due to the physicality of the tape being stressed as their materials loosen and tighten their physical structures - materials that make of the tape base and the binding agent potentially become misaligned, shifted and even detached from the other - but this is a perfect scenario for mold to grow on the media. It's kind of gross but just like mushrooms growing out in the woods, if your tapes are exposed to moisture, and a relative humidity level is maintained or fluctuates high and low, that is a perfect scenario for mold to grow. 

How do we know if tapes are moldy? You can physically see it! It can look like a very obvious growth, as in the picture above with the tape on the cleaner where you can easily see the mold present on the tape. It can also be more subtle, sometimes just small dots that you might confuse as dust or dirt. Sometimes the mold is more attached to the spool plastic than the tape itself, but this still would warrant a cleaning, especially if the mold is still active and growing. 

If you play a moldy tape in a player, not only are you putting your tapes at risk of damage, but the player itself. You would need to perform a very thorough cleaning for that player and even after that you can't be totally sure mold was not released into the player, providing the potential for it to latch on to your next tapes and affect playback.

Dried mold on Lomeli's tapes

So these tapes belonging to Nancy looked a little different but we knew immediately that it was a moldy situation. As we attempted to wind Nancy's tapes back and forth on their spools we noticed the tape was sticking to itself. Immediately we noticed the mold seemed more dried and sticky, even brownish, potentially a scenario where dust had interacted with the mold when it was more active and in its moist environment. If we were to put the tape on a cleaner the tape likely would have ripped.
 
Cleaning by hand

We decided to switch modes into a more meticulous and time-consuming method for cleaning - by hand. We used 91% isopropyl alcohol on a small foam swap and saturated the tape underneath its spools enough so that it could begin to unstick itself from the rest of the tape and the sides of the spools. As we cleaned in this way we hand-wound it, making sure the other spool was clean as the tape arrived on it. Once we painstakingly accomplished this hand cleaning and winding, the tape was able to move more easier onto it's spools and looked much cleaner so we assembled it back together and was able to finish the cleaning by using our tape cleaner. 

It was a time-consuming process, but there is no other way this tape could have been rescued from becoming not only "lost" media, but lost precious memories for our Patron Nancy Lomeli and her family. We love being able to provide this service - and it's all the more worth it when we to hear feedback like this:

 "All my cousins who appear in the videos were very grateful for T.A.P.E. saving our VHS" - Nancy Lomeli 



Her mother will be traveling from Mexico for a visit this year - and we're very excited to hear she is bringing us more tapes to transfer! 

T.A.P.E. is a 501(c) 3 non-profit dedicated to faciliating access to analog media making, preservation, and exhibition. To support our work and access great benefits, join our patreon at just $5/month. You'll get access to exclusive rates for our rental equipment library, access to our digital and physical videotape library, and other member benefits like free workshops. 

We've launched a $6,000 goal for GoFundMe to buy essential digitization equipment to provide more archival transfer services for more tape formats. A donation will advance the work of people-oriented digitization services!

info@tapeanalog.org


Blog written by Jessica G.Z., T.A.P.E.'s Founder and Executive Director.


Friday, September 20, 2024

T.A.P.E. Analog Filmmaking Proficiency Series

Join our Patreon at just $5/month to access great classes like this! 
    Celebrating a summer of amazing preservation efforts, including the launch of Home Video Day in August, we were ready to get back to filmmaking workshops. Past participants have asked us for more hands-on time with the cameras and developing tanks, with the goal of developing greater knowledge and fluidity with these tools. And as a rental library for our equipment, we want to prolong the life of our tools by handing them off to confident technicians.
 


Bolex H16 Rex 5 Proficiency Series

Tuesday, August 27 & Tuesday, September 3, 2024 

We are able to offer these classes for free through the generous donations of Jessica G.Z. and Darrell Brett. Jessica, T.A.P.E.'s founder, is passionate about sharing their knowledge gained with over a decade of analog filmmaking and projection experience. Darrell graduated from CalArts where his focus was the photochemical process, cinematography and projection. He is the head projectionist at Brain Dead Studios on Fairfax, where Jessica projects film and video as well.

The first two workshops covered essential skills and knowledge about the Bolex Rex-5 camera, currently available for rental at just $25/day for T.A.P.E. members. Participants learned essential skills such as: 

  • Identify all the parts of the camera
  • Read a light meter
  • Set diopters to their eyesight
  • Focus their image
  • Load 16mm film
  • Understanding shutter speed & shutter angle

They also got to play with some of features that make a Bolex Rex-5 magical such as: 
  • Double exposure with the frame counter and wind key
  • In-camera transitions
With their combined experience, our teachers offered advice on analog and digital workflows, including essential knowledge on accessing affordable developing and scanning lab services. These conversations empowered new filmmakers to be informed so they can talk to these technicians fluidity and with confidence, getting the results they want. 



Before renting the Bolex, we require passing scores for a proficiency test, ensuring that the filmmaker can confidently care for our equipment. Those who attended the workshop were prepped for this proficiency test!

Lomo Tank Proficiency Series

Tuesday, September 10, 2024

The following week, Jessica led a Lomo Tank Proficiency workshop to prepare filmmakers for the essential skills in home developing motion picture film. Home developing can often be intimidating, so these essential skill workshops break down some of the more technical aspects to loading film into these specialty tanks. 


Donated to T.A.P.E. by Mono Non Aware, the Lomo 8mm/16mm tank allows you to wind 2 rolls of small-gauge film into slotted grooves for even distribution of developing liquids.

It's magical to see how filmmakers get excited about home-developing projects, realizing the potential of saving money and experimenting visually.

Join our Patreon at just $5/month to access great classes like this! 

See more workshops and screenings at whammyanalog.com

T.A.P.E. Equipment Rental Rates for Patreon Members

To schedule an equipment rental, email info@tapeanalog.org

BOLEX H16 REX 5 -- $25/day $110/Week
Lomo Tank -- $20/day $75/Week