Fun with PhotoDoc: New and Improved UV Setup

You may recall back in September of 2018 when we shared an article I had written in our UC Libraries’ newsletter about photographic documentation in the Lab and a recent workshop I had attended through FAIC: http://libapps.libraries.uc.edu/source/photo-documentation-in-the-preservation-lab/  If you missed it, basically the workshop focused on a standardized and replicable UV/visible fluorescence documentation workflow, and was taught by Conservator Jennifer McGlinchey Sexton at Duke University.  It was a fantastic workshop and I came back from it with a plan for a new UV workflow and a list of equipment for an improved UV setup.  However, conservation photography equipment can be pricey, especially when you are embarking on improving a very specialized setup, like UV.  On top of that we had just included a Near Infrared workflow into our photography repertoire and our budget was feeling the strain.  So we took the smart approach and slowly bought equipment, here and there, when the budget allowed.  Finally, we now have all the equipment we need for the new setup.  Check out the results from today’s session:

Left: normal illumination, Right: UV radiation

Lucky for me, when it came to refreshing myself on the actual workflow I had learned at Duke the binder that Jennifer had put together for each workshop participant was incredibly thorough and all I needed to replicate the workflow in the Lab.  Before we dive into the aspects of the new workflow and why it is “improved”, let’s discuss our previous workflow for a second.  Like most conservation labs, we refer to The AIC Guide to Digital Photography and Conservation Documentation (currently on sale for $20!) for almost anything PhotoDoc-related.  For UV, the book details the different types of ultraviolet radiation, various types of UV lamps, safety (both for the object and yourself), setup, filters, and workflow.  In this volume the basic workflow describes using the camera’s “shade” white balance setting and then adjusting the temperature to 10000K and the tint to +35 in CameraRaw.  Exposure is determined by the photographer using visual cues alone, as there is no way to white balance using a standard color checker; the Neutral 8 (N8) patch will no longer be neutral grey under UV fluorescence. 

While this workflow produces very usable images that illustrate the fluorescence of materials, inks, pigments, adhesive and staining, it is subjective and makes replication of results more difficult. While our prior workflow for UV photography could use improvement, the workflow itself was not the main issue, in fact, this is the workflow used in many other labs.  The problem child of our setup was the equipment, and I’m sure any lab trying to piece together a completely brand new PhotoDoc studio (which happened six years ago for us) on a budget can relate.  Behold our previous “UV” lamps, which I affectionately referred to as the “Home Depot setup”:

Good ole black lights!  Though, unfortunately, we did not have a velvet Elvis black light poster hanging in the studio to really take full advantage of these babies.

If we’re being honest, these low-pressure fluorescent lamps were super cheap and served their purpose for 6 years.  Shooting with them was a bear; since the intensity was very weak, I would have to shoot with both lamps and we did not have any clamps to hold them in place. I had to either get someone to assist me or, once I got a wireless mouse, I got even more creative (ask me about it sometime – it’s pretty funny).  The downside of these inexpensive lamps is the significant and noticeable visible light leakage.  Since the fluorescent tubes are not properly filtered, the image you are left with has a blueish-purple cast to it:

  • Notice the blue cast to the background in this image.
  • In this image the blue cast is more apparent on the parchment page and the color checker.

Now onto the new setup!  The main components include:

  • 1 – REL C4 Magnum-GO lamp* – this is an LED lamp with a peak output of 368nm.  It comes with a filter over the radiation source, therefore eliminating visible light leakage from the lamp.
  • Taget UV and UV Gray Card – this color checker and gray card are specially designed for UVA fluorescence photography and allow you to white balance prior to imaging (gray card) and identify the RGB values (target). 
  • Impact Super Clamp – to hold lamp for hands-free tethered imaging
  • Filters (which you should have regardless of your setup, but we did not have them previously) –
    •  2E – cuts UV and blue
    • PECA 918 (or equivalent, we have a Hoya IR Cut filter) – cuts IR even more
    • We also purchased an adapter in order to fit both filters on our smaller 50mm lens
  • UV Glasses (always part of our setup but worth mentioning) – safety is very important and we purchased these goggles because they easily fit over eyeglasses.
Right to left, top to bottom: filters, SuperClamp, UV Glasses, Target UV, UV Gray Card, REL lamp

Fun facts about the REL lamp: The intensity of the lamp and the handle make it great for quick examination.  It has a normal LED built in as well and you can have both functions on at the same time, making it easier to see if you’ve turned your studio lights off or if you want to do a quick comparison of normal illumination vs UV radiation.  As with any UV radiation source you want to keep it away from your object until you are ready to image.  When using a radiation source you also want to let the lamp warm up for at least one minute before imaging (away from the object or with the object covered).  This is because when a lamp is initially turned on it can emit up to eight times more UV radiation, and allowing the lamp to warm up gives the output levels a chance to even out, making it much safer for the object.

Fun facts about the Target UV & UV Gray Card: I know the target and gray card are extremely expensive and not feasible for everyone, but there are definitely advantages to them if you have the budget to invest in the pair.  Not only do the target and gray card allow for white balancing, thus giving you a more accurate color temperature and color representation, but the target is also double-sided and has 4 separate intensity levels: low, medium, high and ultra.  This basically means that you can image a wider variety of fluorescence intensities without sacrificing exposure or color representation.  For example, if you have an object with a layer of varnish on it that only mildly fluoresces, you would probably use the “low” intensity patch to white balance, whereas if you have an object with optical brighteners (extreme fluorescence), you would likely use the “ultra” intensity scale.  This makes it very handy if you have one object that has multiple materials/inscriptions/staining that are fluorescing at very different intensities.

  • Normal Illumination
  • Low-low intensity
  • Low intensity
  • Medium intensity
  • High intensity

Overall, I am very happy with the new setup and workflow, and I am looking forward to using it more and more in the future.

*In the workshop we used by the REL C4 Magnum LED lamps and these UV Systems SuperBright 3 LW370 lamps.  Both worked beautifully but it seemed as though two of the UV Systems lamps would be needed while I could get away with just purchasing one of the REL LED lamps.  The UV Systems lamps would have also required a much more robust mounting system beyond the SuperClamp because of their weight and orientation.

Jessica Ebert [UCL] – Conservation Tech/Photographic Documentation Tech

A Discovery During Treatment

In July of this year, I had the pleasure of assisting on a photograph treatment of Ronald Reagan, which came to us as part of a collection of items belonging to UC alumnus Benjamin Gettler.  It came with a small handful of very old jelly beans from President Reagan’s desk that Mr. Gettler had taken as a souvenir during his visit. While the image itself was in very good condition, it was mounted to an old backing board, which required removal and cleaning so that the image could be digitized and rehoused.

Photograph of Ronald Reagan, with backing

We started by carefully peeling away the old board. This had to be done very slowly, in order to prevent creasing of the high-gloss surface of the image. The adhesive was rather old, and quite a bit of backing was left behind that would require manual work to get at any information that might have been hiding underneath.
Next, Ashleigh and I set about the finer cleanup. With cotton swabs, very thin spatulas, and generous amounts of methyl cellulose, we removed the remainder of the board and adhesive. This had to be done in stages:

  1. Part one was a very general and simple cleaning of the unmarked portion of the back of the photograph. This portion was mostly yellowed water soluble adhesive that was removed with poultices.

    After backing removal. Look at all that yellowed adhesive!

  2. Part two was much more methodical and time-consuming to clean the center area, as it contained ink and graphite that were vulnerable and also water soluble – which we did not want to loose! The smallest working areas around the ink were very lightly mechanically scraped with a scalpel to remove adhesive and small paper fragments.

    After cleaning was largely completed. The newspaper ID stamp is completely visible.

When the work was complete, we revealed what appeared to be a handwritten graphite inscription, and an identifying stamp belonging to the late Bernie Boston (1933-2008), a photojournalist who was the director of photography for the now-defunct Washington Star at the time the photograph was taken. Mr. Boston was a finalist for the Pulitzer Prize in 1987, and his best-known photograph is known as “Flower Power,” a Pulitzer-nominated 1967 photograph depicting a Vietnam War protester placing a carnation into the barrel of a soldier’s rifle during a protest march in Washington, D.C.  Discovering the stamp was a truly unexpected discovery that provided a new layer of importance!
For long term preservation, the newly unmounted photograph was humidified and flattened and stored in a polyester L-sleeve.

Sleeve photograph after treatment.

The sleeve image was stored in an unbuffered rag mat board package that passes the Photographic Activity Test (PAT), mounted with pressure sensitive photo corners.  A surrogate of the image was created and housed with the jelly beans for context.

Sleeve photograph mounted with photocorners.

Photograph is stored long-term in a mat board package with a window and cover.

For more information about Benjamin Gettler and the jelly beans, check out Alex Temple’s blog posts for the University of Cincinnati Libraries blog series: Jelly Beans and Politics & The Benjamin Gettler Papers Processing Project Now Complete

 

Hyacinth Tucker (UCL) – Conservation Technician
Ashleigh Ferguson Schieszer (PLCH) – Book and Paper Conservator

Closures – that's one secure book

The Preservation Lab is gearing up to co-teach a Book Arts Course with Gary Weissman in the English Department, Spring 2020.  Jessica Ebert and I prepped for the closure session by securing these two books.  The idea of creating this sampler was borrowed, with permission, from our friend and fellow bookbinder Fran Kovac.
Book secured with multiple closure types
That’s a lot of security! From top to bottom – bone clasp, two hole tie, O ring wrap, toggle, and 6th century wrap (wrapped two directions so as to see the design).
Holly Prochaska (UCL) — Preservation Librarian

A Monster of a Treatment

When this mid-19th century Treatise on Operative Surgery came to The Preservation Lab, little did we imagine the twists and turns the treatment would take. We certainly did not expect the treatment to turn into a Frankenstein’s monster, pulling inspiration from three different types of binding structures, although this monster found more successful results than Victor Frankenstein’s.

This 1844 full leather tight-back binding came to us from The Henry R. Winkler Center. The binding was in disarray with both the front and back boards having become fully detached, with only the back board remaining. Very few spine fragments remained, but there was clear evidence of false raised bands. The leather that remained on the spine and back board was severely red rotted. The textblock was sewn on recessed cords and remained beautifully intact. The textblock consists of 360 pages containing descriptions of surgical procedures, as well as 80 illustrated plates depicting some of these techniques.
Prior to any rebinding, the placement of the false raised bands was measured and recorded; the book’s spine was cleaned; the front and back flyleaves were mended and hinged; the back cover was housed in a polyester four-flap; new endsheets were sewn onto the textblock; and the spine was lined. Several of the linings attached will bring us to the first bookbinding structure that inspiration was pulled from…

The Split Board Binding: Because of the large size of the book, a split board binding attachment was chosen to add strength to the board attachment. After the spine of the textblock was lined with Japanese tissue and wheat starch paste, creating a reversible layer, a secondary spine lining with flanges was created out of linen and attached with Jade 403 PVA. This linen is an integral part of the split board structure, as it, along with the first endsheet and sewing supports, will create the “laminated flange” that will be pasted in between the two boards (hence, split board). This flange and split board structure can be seen in the uppermost book model in the stack pictured above.
Now that the book has the structure and stability of a split board binding, we can pull from another binding structure to attach the raised supports…

The “Baggy Back” Binding: A “baggy back” structure, also referred to as a conservation case, is what will allow the spine of the binding to be formed to the spine of the textblock, without being adhered directly to it. Another way to think about it is an alternative to a hollow tube structure. Sized linen was non-adhesively shaped over the spine of the textblock, and was pasted in between the split boards on top of the laminated flanges. The open book model in the image on the left shows what a typical “baggy back” structure looks prior to casing the textblock. Comparing that to how the linen can be integrated into the split board structure, we start to see our Frankenstein’s monster take shape.
To prep for the final stages of rebinding, some elements were added to stay true to the original structure of the book. False raised bands were cut and shaped out of 4-ply mat board to mimic the shape and location of the original false raised bands. Hollow tube segments were also attached in between the false raised bands.

These spine elements will finally be covered up using inspiration from one final book structure…
The Quarter Linen Binding: The book was decided to be finished as a quarter linen binding, instead of a more historical full leather or quarter leather binding for conservation purposes. The third model referenced, shown above, depicts the end result of this style of binding. In this structure the linen is stretched over the spine of the book to add the definition of the raised bands, or in the case of this treatment, false raised bands. The linen also allows for a strong attachment between the textblock and the boards. The hollow tubes laid between the bands allow for a better opening once the linen is in place.
During this treatment the linen was stretched over the spine of the book and onto the front and back boards, making sure the linen is securely and evenly applied around all of the spine elements. The book was then secured in a tying press to ensure definition of the bands.

Turn-ins were properly secured, and the linen was trimmed to the proper length on the boards. A brown book cloth was used to cover the remainder of the boards, the color chosen to mimic the color of the original leather used in the binding. The internal flanges from the split board binding structure (as seen in the right image above), along with the pastedowns, were applied to the inner boards. And no book is complete without a stamped title and a matching cloth covered clamshell.

Using three different book structures to plan this treatment does seem like a Frankenstein’s monster of a project, but the success of the treatment pays homage to the integration of bookbinding techniques we find in book structures throughout history.  And this book will certainly look like no monster when it is on display for tours at The Winkler Center.

Kasie Janssen (PLCH) – Senior Conservation Technician
Photographic Documentation by Kasie Janssen & Jessica Ebert

Protectors of the Book: A One-Page Wonder

The Preservation Lab has the opportunity to help host a Book Arts class for UC’s Copyediting & Publishing (CEP) certificate program here in the Lab. We all get to take part in presenting aspects of the history of the book, book arts, preservation and conservation. I LOVE to create enclosures! The engineering that is involved in the creation of unique, custom fitted enclosures gives me great satisfaction and allows me to problem solve. As we were discussing the roles each one of us would play in this course I was happy to find out that I have the opportunity to contribute some information about enclosures. So as little Easter egg to offer as a gift at the presentation I created a one page wonder to give to each student.  Here is the comic in page order:

If you want to print out your own one-page wonder, here is a jpeg in the correct order:
Chris Voynovich (PLCH) – Senior Conservation Technician

Toolkit Time Capsule

Each of our student workers is given a cubby, a general collections lab manual and a basic toolkit that is theirs to use and maintain throughout their time in the lab.  Before a new student starts working and when a current student leaves or graduates I will take the toolkit and evaluate all the contents to make sure they are all there and in good working order.  Usually when a students graduates and moves on this includes cleaning out years of scrap paper and debris.  And often a complete scrubbing down is in order.  
Over the summer I had several students graduate and leave us, so I had several kits to go through.  When I was washing one of the older toolboxes I noticed some folded paper that was attached to the underside of a tray with masking tape.  I immediately removed it, though it was already partially soaked with water.
Upon further inspection it appeared to be a collection of thoughts, quotations, poems, and a short story written on a piece of paper and a fragment of cloth.  Some were written in ink, others in pen.  I immediately texted the prior owner of the toolbox to see if they belonged to her, but she had no idea what I was talking about.  My best guess is that these are several years old (the toolbox was in dire need of a good scrubbing), possibly dating back to before I was student supervisor and possibly before I even worked in the lab (i.e. 12 years or more).

What a fun mystery to stumble across!  Especially when the most exciting things I usually find when I clean out student toolkits are bent microspatulas, collections of abandoned endbands or ALL the pencils!
Jessica Ebert [UCL] – Student Supervisor | Conservation Tech | Conservation Photography Specialist

Exhibition Prep for Upcoming Show: Real Art for Young Artists

Join us September 15th, 2019 at 2pm as the Public Library of Cincinnati and Hamilton County unveils the newly acquired pen and India ink illustrations from Rosemary Well’s Noisy Nora in the beloved nook in the Children’s Library.  The illustrations are richly hand colored in watercolor, colored pencils, acrylic ink and gauche pigments.  With so much detail, they are a treat to see in person!
Acclaimed author and illustrator, Rosemary Wells, has written many endearing children’s books, including Noisy Nora (a story about a mischievous young mouse) and an entire series about the bunnies Max and Ruby.  As part of Ms. Well’s initiative, Real Art for Young Artists, Rosemary Wells has generously offered the Public Library of Cincinnati and Hamilton County the opportunity to exhibit more than a dozen original drawings for long-term display in the Children’s Library located in the Main building downtown.

Since the spring of 2018, the Preservation Lab has been collaborating with colleagues in the Public Library’s Programming, Digital Services, Cataloging, and Facilities departments, as well as the artist herself, on an exhibition of Wells’ Noisy Nora illustrations.  To prepare the materials for long-term exhibition each department lent their expertise to ensure a balance between preservation standards, viewer’s needs, and the artist’s vision.   This blog post highlights some behind the scenes activities leading up to the exhibition.

Above is an image of the nook in the Children’s Library selected as the exhibition space for the illustrations.  The nook is a perfect spot where the light can be controlled, preventing the artwork from fading overtime and it’s a great place to showcase the art at a height children can easily interact.  Facilities updated the nook with new paint and wall decals where the artwork will be hung.  In addition, to inspire young generations to create their own artwork, seating and tables for crafts will replace the current audio visual shelving and television.

At the Lab, approximately 16 pen and ink drawings and one booklet were received directly from the artist as a group within a folder. Many drawings were attached to illustration boards with translucent overlays wrapped around from behind, taped into place, giving the feeling as though they were just recently mocked up for production.    Graphite notes to publishers were written on the transparent papers to inform the size the images should be enlarged or reduced for printing.  While not exhibition ready, seeing the artwork in this preproduction state is a rare glimpse into the creative process of the artist!

After the drawings were carefully removed from the illustration boards, using conservation tape removal techniques, some unique features were discovered on the verso of two illustrations.  The drawings were digitized to document their condition prior to exhibition.  Digitized images of the backs of two illustrations are shown below.

Left: Verso of “And then she dropped her sister’s marbles on the floor” showing an impression of a Windsor and Newton watermark. Right: verso of “No Nora in the Mailbox, No Nora in the Shrub” with a prior sketch crossed out on the back.


To visualize how the illustrations would look in their frames, mock up window mats were created to experiment with how the drawings and captions should be arranged.  Below, the frame on the left centers both the artwork and the caption with a small margin around the art; whereas the frame on the right centers mostly the artwork with a much larger margin around the art.  Ultimately, our aesthetic preference was the extra margin around the art since the artwork itself was not square.  We also decided that no matter what option we chose, we wanted the bottom of the caption to line up throughout all of the frames, whether there was a single or double line of text.

Next, the artwork was measured to estimate material costs for matting and framing.  Following exhibition preservation standards, Rising rag museum mat board, UV filtered glazing, and wood frames were selected by the Preservation Lab.  We choose using glass over Plexiglas glazing so there would be less concern of harming the glazing surface with cleaners.  Because the artwork will be displayed a children’s height level, we also took into account how the artwork will be hung.  With the aid of security locking devices, the frames are not removable from the wall by the public, therefore there will be no danger of the frames falling.
To mimic how the artwork was mounted on the original presentation boards (preserving the artist’s intent), the work was matted with captions from the children’s book added below the art.  The artwork was mounted with Kozo (mulberry) tissue v-hinges that were pasted to the back of the artwork and then adhered to the back mat with with Zen Shofu wheat starch paste.  To maintain a 45% relative humidity environment, the matted artwork was housed within a sealed archival framing package.

Kozo hinges were adhered to the verso of the drawings with Zen Shofu wheat starch paste.


The hand colored drawings were then attached to the back mat using the kozo v-hinges, also adhered with wheat starch paste. The hinges were lightly pressed under weight to dry using pressing stacks.


Landscape window mats were hinged along the top edge with P90 Filmoplast tape.


View of the v-hinges after they are dry.


Drawings are float mounted so the rough cut edges of the drawings are visible.


Recto of sealed framing package.


Verso of sealed framing package.


The framing package contains:

  1. UV filtered Tru View Museum glass (purchased from our local art supply framing store).
  2. Float mounted artwork with two Usu gami hinges applied with wheat starch paste inside matting system. Window mat hinged to the left edge of back mat with P90 filmoplast tape.
  3. Blue corrugated cardboard used as a backing board to the matting package.
  4. Conservation note loosely set into place for future reference on the back of the corrugated backing board.
  5. Sheet of Polyester film added behind the corrugated board as a moisture proof barrier.
  6. To fully seal the entire package, the edges of all the materials were first sealed with pressure sensitive P90 filmoplast tape. A second foil backed framing tape from University Products (part of the Perma/Seal label line) was applied as a barrier to prevent moisture and gas exchange.
  7. A Dove Gray dust cover was attached to the back of the frames with 3M 415 double stick tape. Barcode labels and an additional conservation note were added to the dust cover.
  8. Lastly, Three security hangers were attached to the back of the frames; two at the top and one at the bottom.

With the exception of one frame, the original metal prongs were reused to secure the matting packages within the frame.  The one exception includes the booklet mounted with a sink mat, this thicker package required nailing brads secured to the inside of the frame rabbet to hold the matting package in place.

Booklet was mounted within a sink mat to account for the thickness of the object.


Before exhibit prep:During exhibition preparation:

After installation (the art is hung at children’s height!):

During Will Hillenbrand and Rosemary Wells visit on Sept. 15th, they discussed inspiration for books such and Max and Ruby (who are modeled after Ms. Well’s own children!) and delved into the subject of creating a “noisy” book. Mrs. Wells explained her process of conveying sound through illustrations – which by nature are a silent, quiet experience.

You can view the treatment report and treatment documentation for this original artwork on the Preservation Lab’s Digital Resource Commons site here.
Ashleigh Ferguson Schieszer (PLCH) – Book and Paper Conservator
Photographic Documentation by Ashleigh Ferguson Schieszer, Jessica Ebert & Sidney Gao

Navigating to the Preservation Lab's digital collections

Today UC Libraries unveiled our new website design at https://libraries.uc.edu/.  It is streamlined, meets accessibility standards, and is quite lovely.
However, this website refresh has altered the path users previously followed to access the Lab’s treatment reports. The new path is as follows —-  From the main page top navigation bar choose Research and Teaching Support, then pull down to select Repositories.  UC Libraries homepage with pull down revealing Repository link.From the Repositories page choose UC Digital Resource Commons (DRC).  You’ll then be directed to the main DRC search page.  Here you can limit your search to the Preservation Lab’s collection.
Accessing the Preservation Lab collection from the DRC search page.Or, for those power users, simply bookmark our digital content landing page – http://digital.libraries.uc.edu/collections/preservation/
Preservation Lab DRC landing page
Access to individual treatment reports remain linked within the library catalog’s item record level holdings as well.
Thanks for your patience during this time of change and transition.
Holly Prochaska (UCL) —- Preservation Librarian
 

Book Arts – 3 simple structures

variation on a blizzard book

Crown book completed during workshop


Occasionally the lab is asked to teach simple book structures to students in other academic departments, usually to assist with the physical presentation of their final projects.  Here is the slideshow presentation that accompanied our on-site training for a photography class for the College of Design, Architecture, Art, and Planning on 7/15 and 7/16/2019.
Structures included an accordion book and crown book, with bonus instructions on a one-page wonder that can be made outside of class.  Click the link below to access the slideshow and Enjoy!
https://mailuc-my.sharepoint.com/:b:/g/personal/prochah_ucmail_uc_edu/EXm-2wHSzLtGqERd9T2UaSYBfDnS6ArPWSJdX-Ei4cQxCw?e=lhE9Rz
 
 

The Protective Power of Interleaving

You might know the importance of a protective enclosure, but how often to you consider the quality of storage materials?  In fact, the composition of storage materials plays a significant role in the preservation of archival collections.  But how?
Since storage plays a passive role, the positive and negative interactions of storage materials may not be readily apparent.  Chemical reactions that occur between library and storage materials are often a slow process, spanning over a number of months or years before a visual change occurs.  Without the gratification of seeing immediate effects, many may not realize how some storage materials can be problematic, let alone the ramifications for using non-archival materials.

 
To illustrate some of the effects, I thought I’d share a vivid example of protection from acidic materials during storage. The following photograph shows the positive effects of archival buffering paper (also known as interleaving), as well as the danger of using non-archival boards and tapes – even when they are not in direct contact with the object!
The protected object is a 17th century printed broadside.  It’s a single sheet of paper with printed black text on the front.  The broadside was stored for many years in a green cloth-covered portfolio.

Within the portfolio, the broadside was secured beneath with folded sheets of plastic film with a blank sheet of paper.  You can see the plastic film is attached to the portfolio around the edges with green tape.


This image shows the front of the blank sheet of paper stored side the plastic film, below the broadside. The plastic has yellowed overtime.


Here, the blank sheet is removed, revealing yellowish-brown discoloration around the top and right edge. This discoloration aligns perfectly with the green tape that is adhered on top of the plastic –located on the top and right side of the plastic.


When you flip the paper over, the back of the blank sheet shows even more discoloration. In fact, the discoloration is a mirror image of the materials below the plastic! This has occurred because the plastic is “breathable.” The materials below are all acidic, except for the white fragments of paper, which protected a portion of the paper from turning brown.


The interleaving paper served two purposes here:

  1. Acts as a support for the broadside when handled.
  2. The interleaving served as a sacrificial barrier that absorbed the bulk of acidic off-gassing from the non-archival paper and tape.

In summary, this enclosure is an excellent example of how different materials can interact with one another in nuanced ways, and how plastic is actually a permeable barrier to gasses overtime!
General storage tips:

Ashleigh Ferguson Schieszer (PLCH) —- Book and Paper Conservator