lelgin | c u r i o

Stereoscopy Digitized

May 21, 2015 by lelgin | 1 Comment

Last fall, the Brown University Library acquired a set of 100 stereographs made of Palestine in 1901. Stereographs are made using stereoscopy: a technique that involves creating the illusion of three-dimensional space using two-dimensional imagery. In photography, this means making two images that are just slightly offset from each other, and using a special viewer (a stereopticon) to look at both images at once. The illusion of depth between different spatial elements emerges as our brains attempt to reconcile these two different images into one, creating a (seemingly) three-dimensional scene.

One of the stereographs of Palestine, showing the two offset images that will eventually form the single three-dimensional image.

As is the case with most stereographs of this kind, these photographs are albumen prints that have been mounted onto thick card stock. Over time, many of these cards develop a curvature towards the mounted-print side. This makes it very difficult to digitize the images using a flatbed scanner; you can’t get even focus or lighting on a non-flat object, and it’s easy to rip the images or crack the emulsion of the photographs if any attempt is made to flatten the cards. This set of stereographs was no exception, and many of the cards had a distinct curve to them. To account for this, I digitized them using our reprographic camera so I could light them effectively and avoid the need to flatten the object altogether.

3dslidermaker

The next step was to create a three-dimensional image from each stereograph. There are a number of software applications that enable the user to merge two images from a stereograph into a single image that can be viewed as three dimensional using 3d glasses. I chose 3d Slide Maker, a freeware Macintosh application made by Mike Cook. This software lets the user upload the left and right sides of the stereograph, and then adjust the level of offset on the horizontal and vertical axes. It’s easy to view changes are you make them, so if you have a set of 3-D glasses you can check your work as you edit. This software also allows for additional imaging adjustments to correct any problems that creating the final 3-D image, or anaglyph, has caused in the image quality.

Once each new image was complete and exported, it was added to the collection of images. Each stereograph has three images associated with it: the front of the card; the back of the card (many of these have writing about the scene pictured on the front); and the 3-D anaglyph. If you have 3-D glasses, you can view the image below as a representation of what viewing the stereograph using a stereopticon might be like. You can also click here for an animated gif that shows the offset of the images.

Palestine033_03d

This collection will be displayed at Brown through 100 stereoscopic viewers in Fall 2016, curated by Ariella Azoulay and Issam Nassar, under the title Time Travelers in Palestine – Stereoscopic Journey.

Portrait un-retouching

April 21, 2015 by lelgin | 1 Comment

A few weeks ago, I was given a photograph to digitize – a pretty standard request in DPS. The photograph is a portrait of Alexander Nesbitt, co-founder (with his wife Ilse Buchert Nesbitt) of the Third & Elm Press; the Brown University Library has a sizeable archive that includes “art and design work from the Third & Elm Press; in part, joint art and design work of Alexander Nesbitt and Ilse Buchert Nesbitt for other than Third & Elm; and in part the papers of Alexander Nesbitt, including correspondence, writings, miscellaneous papers, academic papers, non-academic lectures, biographical/personal materials, and museum objects” (from Brown University Library catalog record).

before It’s a lovely portrait, and one of the only portraits of him from that time period. The only problem? At some point, the image was retouched to mask out a large area around Mr. Nesbitt’s face – giving this unusual halo effect that proved very distracting. Normally, our archival digitization workflows aim only to capture the originals as accurately as possible, but this was a special case for this particular collection, so we decided that we would keep two copies of the scan that I’d made. We kept one version that included the original retouching, and a new version where I eliminated the halo, and attempted to recreate as best as possible the image underneath. We would add both versions to the Brown Digital Repository, and also wanted to be able to make new prints of the image – printed using archival processes and fine art papers – that we could use for display to protect the original from damage.

The photograph itself was also showing some aging and use problems: there were some minor color shifts in the photograph (the sepia-ish light brown tone was turning to yellow-orange in the highlights), and there were some bends and tears in the paper. I was able to correct those relatively easily using straightforward image processing techniques. I also removed some dust and scratches from the original printing. Then, I moved on to the main job: removing the while halo, and recreating all the areas underneath the white mask. This was relatively easy to do when it came to the background, but when it came to Mr. Nesbitt’s neck, suit, shirt, and tie, it was far more challenging to recreate an accurate and convincing image.

I was able to determine how to recreate the tie relatively easily – I did basic image searches for men’s ties and tried to find some good matches to work from. The shirt and coat lapels were trickier, because they’re a specific style. The coat lapels in particular required a little more investigation, especially to get the notch correct and to make sure the angles and spread looked right. Here, my research led me to Hollywood:

I used these images from Indiana Jones and the Temple of Doom (1984) and The King’s Speech (2010) as guides in recreating the suit jacket for Mr. Nesbitt. I did not use the images to add to the file I was working on; rather, I used them as reference as I recreated the lines, textures, and shadows of the jacket through various processing techniques. When retouching was complete, we had prints made of both images: the original with basic color adjustments and tear repairs, and the fully retouched version with the halo removed. Here’s the before and after, from raw scan to completed file:
before-after

The Unicorn of the Sea Comes to Brown

March 10, 2015 by lelgin | 2 Comments

I often write about techniques to photograph unusual objects, or situations that involved photographing objects on site. This past Friday, however, we had the unique pleasure of photographing a very rare and unusual object while it was being installed for exhibition. My colleague and I photographed a narwhal tusk from the Paul C. Nicholson Whaling Collection of the Providence Public Library, on loan to Brown for the exhibit Unicorn Found: Science, Literature and the Arts. The exhibit, as well as a special Unicorn Colloquium the afternoon of March 11, are part of the larger, multi-institution Unicorns in Residence: Providence event this spring.

tusk01

The Narwhal tusk is remarkable to view in person; I was surprised at its size (56″ long), and its hollow, spiral structure. In a previous discussion about photographing this object, it was decided that the safest and most efficient time for photography was during installation of the tusk, so it would be handled as little as possible and by the folks who specialize in handling these materials. (While my colleagues and I are familiar with many special handling techniques for rare and fragile objects, the narwhal tusk requires multiple people to handle, and while its age is unknown it is a decidedly delicate object.) All object handling was done under the direction of Jordan Goffin, Special Collections Librarian at the Providence Public Library, with the assistance of Rachel Lapkin, Materials Conservator at Brown (who also made the stands that support the tusk), and Sarah Dylla, a Public Humanities graduate student at Brown working on a fellowship in Special Collections.

The tusk in its display case at the Hay, prepared for photography with gray backdrop and studio lights. The camera, tethered to an out-of-frame laptop, is mounted on a tripod on a table to obtain a suitable height and distance from the object.

The tusk is housed in a display case that can be viewed either from the main lobby or the Grand Reading Room at the Hay. After looking at the space prior to photography, we decided to photograph the tusk in its display case, with a neutral gray backdrop set up temporarily for photography. We set up the backdrop, two lights to illuminate the tusk, and then the tusk was moved into place. We had decided to photograph it from several angles – straight on, and from multiple side and front views – so we made several images from one vantage point, and then moved on to additional angles and views.

Alternate views and detail of the narwhal tusk.

The tusk, and a number of other curious unicorn-related materials, will be on display in the John Hay Library in the renovated lobby cases and Willis Reading Room cases from March 11 – July 31, 2015.

Capturing the Transit of Venus

March 2, 2015 by lelgin | 1 Comment

Recently, as part of Brown’s 250th celebration, my colleague and I were asked to photograph a selection of the many historical objects at Brown. Among these was the Transit of Venus telescope, a Gregorian reflecting telescope made by Watkins and Smith of London, and donated to the University by Joseph Brown. The telescope is named for the event it was purchased to observe: the movement of Venus across the sun. The transit of Venus was observed by Brown, Benjamin West, and others on June 3, 1769 – and more recently on June 5, 2012.

The final version of the Transit of Venus telescope, photographed on site in the Lownes Room.

Thankfully, my colleague and I did not need to address any planetary movements to photograph this object; however, we did need to photograph it on-site in the Lownes room at the John Hay Library. We brought our backdrop, lights, and camera, and it was a relatively simple setup. We were careful to set up the camera so that the lens and angle of view did not distort the telescope in any way; our main challenge was actually positioning the lights. The telescope is incredibly reflective, and while changes in tone help show the shape of the telescope, and some highlights are useful for showing surface texture, initially we were getting long streaks of blown-out highlights, causing a visual distraction within the overall image.

Our straightforward lighting setup gets the job mostly done – all we have to deal with is the large highlight streak in the center of the telescope.

After trying multiple approaches – from changing the position and distance of the lighting, to a system of reflectors – we decided that our best option was to make two captures to merge together. To keep image distortion to a minimum, we decided to keep the setup largely the same, but to reposition the angle of one of the lights for each shot. Once finished, we had one image that was properly exposed except for a blown-out streak on the right side; and another with the lighting problem on the left. Layered in Photoshop, it was easy to merge the images to create a single image that accurately captures the telescope without the distracting highlight.

The two vies of the telescope – the only differences are the positions of the highlights, created by repositioning and changing the angle of our lighting equipment to reduce the glare.

Photographing the Edwards Cane

January 23, 2015 by lelgin | Comments Off on Photographing the Edwards Cane

Shortly before we left for our holiday break, I had another opportunity to photograph historical materials and objects from the Brown University Archives. We’ve had a number of interesting objects come through lately as part of Brown’s 250th celebrations, and since we often are photographing books and documents, three-dimensional objects can be a treat to have in the studio.

One of the more challenging objects that I got to work with is known as the “Edwards Cane,” a cane that belonged to Morgan Edwards, an important figure in the founding of Brown University. The bottom of the cane is rounded and does not stand on its own; it also has an ivory head with a small silver plate bearing an inscription. It was important to shoot both the cane overall as an object, but also focus in on the inscription.

Edwards Cane; full shot (L) and detail of inscription (R). The hole in the cane visible in the detail shot, just below the ivory handle.

Usually, when we are given more complicated objects to photograph, it’s the nature of the surface materials that presents the greatest challenge: oil paintings, for instance, that are prone to glare; or objects made of silver or glass, which require the construction of light tents in order to capture the details of the object without also capturing our own reflections. The Edwards Cane, however, posed a new challenge: how to adequately support the object while keeping the intrusion of the support elements into the image at a minimum. The best way to photograph it would be to build a support that gently but firmly clamps onto the cane and holds it at a precise position, so we could have the exact angle we wanted without damaging the cane. However, despite multiple attempts, I was unable to find any support mechanism that would support the cane well, not allow any movement, not cause any damage to the cane, and not be incredibly difficult to digitally remove from the final image.

The cane with packaging tape support.

And then I found the trick. The cane actually has a hole running through it a few inches below the top, visible in the detail of the inscription. The hole runs through the width of the cane and is lined in metal; it’s sturdy, and at just the right spot as a center of gravity of sorts. It was perfect – I just had to find the right material to run through this hole to keep the cane supported and at the correct angle. After trying multiple types of rope, twine – even extra strong fishing line – the material that worked best was regular clear packing tape. When folded over itself, the packing tape leaves no residue behind on the object, and it’s possible to fold it in odd shapes as you go. This was important, because I was able to create small bumps on either side of the cane, which did not cover any of the object when photographed but did keep the cane perfectly in place. The cane is very light, so this turned out to be the perfect option for keeping it in place. I ended up using two additional, much more powerful tapes to attach the packaging tape support to the wall and desk of the studio, to keep the cane in the correct position (this technique actually allowed me to change positions easily, so I could angle the cane and capture the inscription without having to reposition the entire setup).

Once the support was in place, the rest of the setup was straightforward. I positioned two lights with umbrellas as well as a simple grey backdrop, and was even able to shoot tethered with our high-resolution digital back (very important in checking the focus, especially on the inscription). I was able to capture the front, back, and a few details relatively easily, only needing to move the lights and slightly adjust the angle of the cane. Adjusting the cane was not a problem, but I waited approximately two minutes after I made any adjustments for any movement I created to cease. The final images did require some minor retouching – mainly just removing the evidence of tape from the grey background. The result was a set of high-resolution, clean final images that show all the important elements of the cane, and further proof that no photography studio can have too much tape on hand.

The final setup for photographing the cane, showing the packaging tape support attached to the studio wall and desk, the camera tethered to our capture computer, and a basic lighting setup.

Digitizing the “mirror with a memory”

October 7, 2014 by lelgin | Comments Off on Digitizing the “mirror with a memory”

As we celebrate Brown’s 250th anniversary, Digital Production Services has been asked to digitize many historical university materials. Some of the earliest photographs in the university’s extensive collection are daguerreotypes made of graduating classes, and I was recently asked to digitize two these: the class of 1847; and the class of 1852.

The common reflective characteristics of a daguerreotype.

Daguerreotypes present several challenges in digitization, mainly due to their inherent physical characteristics. Above all else, daguerreotypes are by their very nature incredibly reflective. In this nineteenth century process, the actual photographic image is formed on a silver-coated copper plate that is polished to a mirror-like sheen. Depending on the lighting and viewing angle, even just hand-holding the daguerreotype may provide you with a clear image of the subject, or you may just be staring back at yourself. Additionally, daguerreotypes are often encased behind glass to protect the fragile image resting on the surface of the silver – helpful in maintaining image integrity, but adding another layer of reflection. In order to view the daguerreotypes (as well as digitize them) with any degree of success, you must control the lighting that strikes the object, and completely block out any object that would cause a reflection. Because lighter objects are always more visible in this type of reflective image, photographing a daguerreotype of any size requires surrounding the object with black foam, paper, or cloth that will help offset its reflective properties.

I approached photographing these daguerreotypes the same way I would approach any reflective material: by building what amounts to a tent around the object. Whereas with many objects (highly reflective silver with no printing, for instance) work best surrounded by white paper or foam core (or even semi-translucent vellum), daguerreotypes work best surrounded by all black. Black eliminates reflections, as well as helps make the image on the surface of the silver as clear and readable as possible. The most obvious reflection is often that or the camera itself; since I was photographing the daguerreotype reprographically, the camera was positioned directly above that polished silver surface. The best way to avoid seeing the camera’s reflection in the lens is to take a large sheet of black foam core, cut a small hole just for the lens of the camera, and cover the entire camera rig with the foam core.

Daguerreotype, Brown University, class of 1852: The image on the left shows the camera (with its various wires to the computer and strobes) directly reflected in the daguerreotype; the image on the right shows the same daguerreotype with the camera covered by black foam core.

Although it’s possible to just use a sheet of black foam core to reduce reflection, I built a small rig to hold the foam core up (hand holding it myself could potentially add camera shake) and reduce any reflections from the walls behind the camera (painted a light neutral grey, but still reflective). These photographs show the supports for the foam core and the hole I made for the lens, and then the final setup for shooting.

behind-the-scenes

Additionally, although proper focus is always important, it is particularly important when it comes to daguerreotypes. Daguerreotypes were developed in 1839, and these older processes required much longer exposure times than what we are used to: a typical exposure could last up to a minute or more. Because of this, at the time it was challenging to keep people in focus because it was difficult to keep them still; as a result, it can be tricky to make out faces due to the motion blur. Thus, when digitizing, keeping the focus as sharp as possibly is necessary to producing a readable image. For this daguerreotype, I actually placed the object on several blocks of foam core to focus into the encasement and reach the image on the plate beneath.

Finally, both daguerreotypes are suffering from degradation and corrosion, common problems for this sensitive and fragile type of photograph. They will soon be sent to the Northeast Document Conservation Center for conservation and repair.

Streamlining Broadsides

September 5, 2014 by lelgin | Comments Off on Streamlining Broadsides

Over the past year, Digital Production Services has been working on the digitization of one of the Brown University Library’s extensive collections of broadsides. The Rider Broadsides Collection (named for Sidney S. Rider, the Providence bookseller, publisher, and antiquarian from whom the collection was purchased and then subsequently donated to the university) is the largest privately owned collection of materials related to history of Rhode Island. It’s been a great opportunity to see firsthand such historic materials, and the broadsides themselves have been largely straightforward to digitize.

Just one of many historical documents that DPS has digitized as part of the Rider Broadsides collection.

And the ability to digitize these materials efficiently is important when undertaking such a large project; were the materials all fragile, oversize books with foldouts, digitization could easily take years. But the Rider Broadsides have two important qualities that allow for high quality and high speed digitization: they are mostly flat materials, and many of the broadsides are approximately the same size. Books, for instance, with most setups require constant focus adjustments since the distance from the camera to the page changes as one moves through the books. Likewise, materials with size differences require the camera to be raised or lowered (and then refocused) to accommodate these variations and provide the best quality image. The Rider Broadsides, though, allowed us to set the camera height and focus at the beginning of a session, and then digitize a full day’s worth of work without requiring substantive changes in our setup (spot checks for focus and exposure are always made).

However, once the regular size materials had all been digitized, we moved onto the oversize materials, which present more of a challenge. There are just shy of 400 1-Size broadsides, which vary in size from 12″ x 16 ” to 18″ x 24″ (give or take 1/4″). While this may not seem like such a wide range, going from the smaller size to the larger requires us to either reset everything for each shot (including special compensation for vignetting on the larger materials), or to shoot everything as if it were the largest size. The problem with shooting for the largest size object is that we’d be compromising resolution: as the camera moves further from the object, resolution decreases. We had shot all the regular materials at 600 ppi (at full size), so one of our goals is to maintain as much resolution as possible. So we had to devise an approach to digitizing these materials that would maintain the efficiency as well as the quality that we had achieved with the regular-sized broadsides.

Each of the four groups of broadsides, separated and labeled by size and camera settings.

The answer was to separate out the broadsides by size, and create a specific and easy-to-replicate camera setup for each size range. After going through every broadside, I came up with four size categories: 12 x 16, 14 x 19, 16 x 21, and 18 x 24 (all in inches). All the broadsides fit into one of these size ranges, which allow us to maximize resolution for each size. With a fixed set of size ranges, I went about determining the camera setups. Using just a tape measure and camera target, I plotted where on the camera platform a specific size would fall. I them focused the camera on the target, to see precisely where the camera needed to be to cover the entire image area while in focus. I noted the maximum size of an object for that image area, the resolution that could be achieved, and the height that the camera required (this number is taken from the mounted rail on the camera platform). I made labels for each set of broadsides, which I had separated onto different book trucks.

I also made tape labels for each size range that I affixed to the camera rail. This way, regardless of the person working in the camera room that day, and regardless of which group of broadsides they were working on, all the photographer needs to do is check the label on the stack of broadsides to determine the image size, find the corresponding label on the camera rail, move the camera to level with the label, focus, and shoot. We have digitized hundreds of broadsides so far, and this has turned out to be useful not just for effective digitization, but also for easier retrieval of paged materials.

Details of signage and camera rail markings.

c u r i o

Imaging rare, unusual, and intriguing objects at the Brown University Library

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