Technical Information

Digitizing the Collection

During 2002-2003, JJT, Inc., of Austin, Texas, scanned the Civil War negatives. They used an overhead MARC II digital camera to scan the 7,592 glass negatives (measuring in sizes ranging between 2-1/4 x 3-1/2" and 8 x 10 inches). The images were captured in grayscale at a spatial resolution of approximately 10,000 pixels on the long side and a tonal resolution of 16 bits per pixel. The negatives were scanned with the emulsion side up to protect the fragile surface. The negatives display online as they would have been printed. Words sometimes appear in mirror image because they were notes written on the emulsion side for identification purposes, not necessarily to be printed with the image--the words were often cropped out.

With today's resources, these very high-resolution images require significantly increased costs, particularly in time spent capturing, inspecting, and loading the files. For most collections in the Prints and Photographs Division, online digital images, even at lower resolutions, play an important preservation role as surrogates that reduce handling of the original pictures. Digital images of each negative display in each bibliographic record. Two (or more) digital images display separated or variant views of items in stereograph records to facilitate re-creation of original stereoscopic views.

Specifications for the Negatives

Uncompressed Archival TIFF Images

Spatial Resolution:

7,500 pixels on the long side with the short side scaled in proportion for file names ending in u.tif (17-20 megabytes). Prior to 2023, this version had been scaled down to 5,000 pixels on the long side.

Tonal (pixel depth) resolution:

8 bits per pixel (grayscale)

Image enhancement:

None.

File format:

Tagged Image File Format (TIFF) ver. 6.0

Compression:

None

Highest Resolution TIFF Images

Spatial Resolution:

7,500 pixels on the long side with the short side scaled in proportion (up to 100 megabytes)

Tonal (pixel depth) resolution:

16 bits per pixel (grayscale). Note: Some older versions of image viewers and editing software cannot handle 16 bit images.

Image enhancement:

None

File format:

Tagged Image File Format (TIFF) ver. 6.0

Compression:

None

Compressed Service Images

Spatial resolution:

640 pixels on the long side with the short side scaled in proportion for file names ending r.jpg (25-190 kilobytes); 1024 pixels on the long side with the short side scaled in proportion for file names ending v.jpg (80-460 kilobytes)

Tonal (pixel depth) resolution:

8 bits per pixel (grayscale)

Image enhancement:

Mild sharpening

File format:

JPEG

Compression:

Compressed to yield an average compression ratio of 10:1

Thumbnail Images

Spatial Resolution:

150 pixels on the long side with the short side scaled in proportion for file names ending in t.gif (approximately 20 kilobytes)

Tonal (pixel depth) resolution:

8 bits per pixel (grayscale)

Image enhancement:

Mild sharpening

File format:

Archived copy: TIFF - Tagged Image File Format
Online copy: GIF - Graphics Interchange Format

Compression:

Archived copy: Uncompressed
Online copy: Compression native to the GIF format

Describing the Collection

Most of the Prints and Photographs Division's cataloging is considered "minimal level," because information is often limited to what is provided with the picture rather than what could be learned by fully researching the image. The following comments explain the general cataloging guidelines. They also point out which catalog record information is most useful for citing pictorial materials in research notes or publications. Since the original information accompanying a picture can be inaccurate, the Division is always glad to hear from researchers who have additional or better information.

The records for a single collection might not use each of the fields or have all of the indexing features described here. For more information about cataloging pictorial materials, see the cataloging bibliography.

CALL NUMBER. This string of letters and numbers is used to locate the original material at the Library of Congress. The original work may be requested in order to see details not captured in digital reproduction or to create a new type of copy photograph. A code might display at the end of the call number to identify the custodial division, for example, [P&P] means the item is from the Prints and Photographs Division. Although P&P has a unique system of call number locations (and the patterns vary from filing series to filing series), the call number is still a useful reference citation.

CARD #. The control number, or card number, for each catalog record is a unique identification number. It can be used to do a quick number search when you want to see a specific record without repeating a long keyword or subject search. However, only some online catalogs provide an index by this number.

COLLECTION. The title of the collection associates each item with its source and is useful to include in bibliographic citations. Some items are in more than one collection, because they are associated with both a format-based collection (e.g., Daguerreotype Collection) and a donor-based collection (e.g., Frances Benjamin Johnston Collection). Other items lack a formal collection title heading because they are in collections that have not yet been fully cataloged. Such informal collection names often appear in the NOTES field.

CREATOR. When the name of the photographer, architect, printmaker, or other image creator is known, only one form of the name is used, so that it is possible to retrieve all works by one creator under a single spelling or form of the name. Birth and death dates are included only when such information is readily available. If the Library of Congress form of the name was established while the creator was still alive, a death date is not usually added when the creator dies. It is expensive to update such information, and the name is already uniquely identified in the catalog.

The absence of a creator's name indicates that the creator is anonymous, unidentified, or unknown.

After the name, a term appears to identify the relationship(s) between the name and the work being cataloged. For example, architect, copyright claimant, photographer, or publisher.

DATE. The date refers to the year(s) when the image being cataloged was created, not the time period depicted in the picture.

The date is transcribed when such information appears with the picture. It is difficult to assign a specific year to undated prints and photographs. The catalogers look for clues such as: styles of fashion shown in the image, photographer's life dates, or type of physical media. Often, only a span of years or decades can be estimated, and such dates are shown in brackets, for example, [between 1900 and 1930].

When the single letter "c" appears before a date, it indicates the year in which an image was deposited for copyright.

The abbreviation "ca."means "circa" and indicates a date that is approximate within several years.

DIGITAL ID (or VIDEO FRAME ID). The identification number for the digital file begins with a word or phrase that explains the source used to create the digital image, for example, the "original" work or a "b&w copy film neg." The Library's digital images are often created by scanning one or more of the copy photographs listed in the Reproduction Number field.

FORMATS. The genre and physical characteristics of the original work are listed as plural index terms. Examples include: Broadsides, Engravings, Group portraits, Lithographs--Color, Paintings--Reproductions, Political posters, Portrait photographs, Stereographs, and Woodcuts.

These headings are sometimes subdivided by the nationality, place, or decade in which the work was created. Other subdivisions indicate if the work is in color or is a reproduction of another medium. The terms come from the Thesaurus for Graphic Materials II: Genre and Physical Characteristic Terms.

MEDIUM. The physical properties of the original work are described by listing a readily recognized broad category, such as photograph, drawing, or print, followed by a more specific designation, such as daguerreotype, charcoal, or aquatint. This is determined by examining the work. The description is also a reminder that the physical characteristics of the original work are quite different from a digital reproduction on a computer screen.

The quantity of material is also stated, although most records usually describe only a single item. Some records, however, describe tens or hundreds of items, and it is helpful to know the size of each work to understand the specificity of the information in the catalog record.

The dimensions of a work are rarely provided in minimal-level cataloging. Panoramic photographs, however, include dimensions, which are rounded off to the nearest half inch and measure the image area exclusive of borders and mounts.

NOTES. Many types of notes are written to explain reproduction restrictions, sources of devised dates and titles, the name of the collection to which the work belongs, citations to published versions, and other aspects of the work. A subject description is sometimes written if a title is not self-explanatory. With minimal-level cataloging, some types of notes are omitted, for example, acquisition source is rarely provided.

OTHER TITLE. Additional titles by which the work is known.

RELATED NAMES. When multiple people or corporate bodies contribute to a work, their names can be listed as related, or added, entries. When the nature of the contribution can be specified, a relator term, such as client, copyright claimant, interior designer, or sculptor, is added after the name.

REPOSITORY. The name of the institution and division that have custody of the original work. This information can help you locate or cite the original.

REPRODUCTION NUMBER. This alpha-numeric code identifies existing black-and-white and color photographs from which prints, transparencies, and other photographic reproductions can be ordered. This number is also the most useful (and shortest) reference citation to include with any subsequent publication of the image.

A qualifying phrase identifies the type of reproduction (e.g., color transparency) and points out which reproductions are only details or cropped versions of the original works. This information can help you decide which of the copy photographs you want to reproduce.

The abbreviation "b&w" stands for black-and-white.

SUBJECTS. Catalogers assign index terms that describe what the image shows as well as what the image is about. For example, a political cartoon depicting a basketball game in which the players are dribbling a globe is "of" basketball and "about" international relations. Most of the topical terms come from the Thesaurus for Graphic Materials I: Subject Terms. The proper noun headings come from the Library of Congress Name Authority File and from the Library of Congress Subject Headings. Examples include: Baseball players; Document signings; Dogs; Flags--American; Ford's Theatre (Washington, D.C.); Log cabins; Pan-American Exposition (1901: Buffalo, N.Y.); Presidential inaugurations; Tippecanoe, Battle of, 1811; United States. Declaration of Independence; World War, 1939-1945.

Some collections have only preliminary index headings, and do not use standard vocabulary sources like the Thesaurus for Graphic Materials. For example, the Historic American Buildings Survey/Historic American Engineering Record uses an uncontrolled indexing vocabulary where different terms, such as "Car dealership" and "Auto dealership," are sometimes used for the same subject, because the material being cataloged used those different terms. The Gottscho-Schleisner Collection headings focus on terms for types of structures, for example, "Automobile dealerships" and use few proper names for subjects such as buildings. (The title includes an informal building or project name taken from the photographer's logbook.)

Terms are sometimes subdivided by place and date of depiction. In other cases, the place names are expressed as hierarchical geographic "strings" to allow keyword access to names of countries and states as well as counties and cities. For example, "Canada--British Columbia--Vancouver" or "United States--Maryland- -Baltimore."

TITLE. A title is transcribed from the original picture, or from a photographer's logbook or negative jacket. If the picture carries no caption a title is devised from another source and displayed in brackets. Devised titles are written by Library staff, or they might come from a published book illustration or a former owner.

The abbreviations "[sic]" and "[i.e.]" indicate erroneous spellings or information in transcribed titles. The correct information is provided as needed in the title or a note.

Cataloging Bibliography

General Works

• Besser, Howard, and Jennifer Trant. Introduction to Imaging: Issues in Constructing an Imaging Database. Santa Monica, Calif.: Getty Art History Information Program, 1995.
• Cawkell, A. E. A Guide to Image Processing and Picture Management. Brookfield, Vt.: Gower, 1994.
• Evans, Linda J., and Maureen O. Will, comp. MARC for Archival Visual Materials: A Compendium of Practice. Chicago: Chicago Historical Society, 1988.
• Flynn, Marcy, and Helena Zinkham. "The MARC Format and Electronic Reference Images: Experiences from the Library of Congress Prints and Photographs Division." Visual Resources 11 (Summer 1995): 47-70.
• Hagler, Ronald. The Bibliographic Record and Information Technology. 2d ed. Chicago: American Library Association, 1991.
• Malan, Nancy. "Organizing Photo Collections: An Introspective Approach." PictureScope (Spring 1981): 4-6. (Reprinted in: A Modern Archives Reader, ed. by Maygene Daniels and Timothy Walch, Washington, D.C: National Archives and Records Service, 1984.)
• Muller, Karen, ed. Authority Control Symposium: Papers Presented During the 14th Annual ARLIS/NA Conference ... 1986. Tucson, AZ: Art Libraries Society of North America, 1987.
• Orbach, Barbara. "So That Others May See: Tools for Cataloging Still Images." Cataloging & Classification Quarterly 11, no. 3/4 (1990): 163-191.
• Ritzenthaler, Mary L., Gerald J. Munoff, and Margery S. Long. Administration of Photographic Collections. Chicago, IL: Society of American Archivists, 1984.
• Robl, Ernest H. Organizing Your Photographs. New York: Amphoto, 1986.
• Schultz, John and Barbara. Picture Research: A Practical Guide. New York: Van Nostrand Reinhold, 1991.
• Shatford, Sara. "Analyzing the Subject of a Picture: A Theoretical Approach." Cataloging & Classification Quarterly 6 (Spring 1986): 39-62.
• Zinkham, Helena, Patricia D. Cloud, and Hope Mayo. "Providing Access by Form of Material, Genre, and Physical Characteristics: Benefits and Techniques." American Archivist 52 (Summer 1989): 300-319.

Tools

• Anglo-American Cataloguing Rules. 2nd ed., 1988 rev. Chicago: American Library Association, 1988.
• Art & Architecture Thesaurus. 2nd ed. NY: Oxford University Press, on behalf of The Getty Art History Information Program, 1994. 5 vol.
• Library of Congress. Library of Congress Rule Interpretations. 2nd ed. 1991- . 2 vol. **
• Library of Congress. Library of Congress Subject Headings. 18th ed. 1995. 4 vol. **
• Library of Congress. "Name Authority File" (available online through internet //lcweb.loc.gov)
• Library of Congress. Subject Cataloging Manual: Subject Headings. 4th ed. 1991- . **
• Library of Congress. USMARC Format for Bibliographic Data. 1994. 2 vol. **
• Library of Congress. USMARC Format for Authority Data. 1993. **
• Library of Congress. Prints and Photographs Division. Thesaurus for Graphic Materials. 2nd ed. 1995. 2 vol. TGM I: Subject Headings and TGM II: Genre and Physical Characteristic Terms. (Also available on the Web.) **
• Parker, Elisabeth Betz, comp. Graphic Materials: Rules for Describing Original Items and Historical Collections. 1982. Updated in August 1996 on the Cataloger's Desktop. **
• ** : available from LC Cataloging Distribution Service, Washington, D.C. 20541-5017

Arrangement and Online Access

Search Tip

The online catalog records have variable content. Try general searches, particularly when searching for people. Consult lists prepared by staff for some frequently requested subjects.

• Information in the catalog record that accompanies each scanned negative was taken from the paper sleeve which housed the negative, or the Civil War caption books kept in the Prints and Photographs Division.
• No attempt was made to standardize names, spell out abbreviations, or to research the image.
• If you are searching for portraits, you will retrieve the most hits by entering only the last name of the person being sought.
  For example, a search for "Lee" will yield many more images of General Robert E. Lee than more specific searches for "Robert E. Lee" or "R. E. Lee."
• The original captions do not systematically include words for subjects such as "women" or "African Americans," so searching using such words does not yield very much. P&P staff have compiled lists (available via the P&P Reading Room site) of images from the collection that include:
  • African Americans
  • Women
  • Enlisted Men

In cataloging Civil War photographs, Prints & Photographs Division staff generally work from the original caption material that was received with the negative or print. Sometimes this information is incorrect or outdated. An online form is available to suggest corrections to the catalog records.

Glass Negative Series

In organizing the glass negatives, the Library grouped them by source (Anthony-Taylor-Rand-Ordway-Eaton Collection or Brady Handy Collection), size, and broad subject areas. In 2002 the Library scanned those groups that consist primarily of original glass plate negatives. The groups that consist primarily of duplicate and copy negatives were not scanned. Online catalog records were made for negatives that were scanned.

LC-B811

2,926 original individual wet plate stereo pairs negatives and some copy negatives, 4 x5" and smaller, 1861-1869 (1,063 unique images). These stereo negatives are sequenced so that the images can be viewed as three-dimensional ("3-D") images when seen through a viewer. (For information on resources for viewing digitized stereographs in 3-D, see "Viewing Online Stereographs in 3-D," in the "About the Stereographs" section of the online catalog.) Negatives by George Barnard, Samuel A. Cooley, James Gibson, Timothy O'Sullivan, and Alexander Gardner. Many of these negatives were listed in Alexander Gardner's 1863 Catalogue of Photographic Incidents of the War. Mainly war views, including:

• fortifications in Yorktown and Petersburg
• dead soldiers on the battlefield at Gettysburg and Antietam
• portraits of officers and their staff
• ambulance corp on the battlefield
• city views of Atlanta, St. Augustine, and Savannah
• Libby Prison, Richmond, and a slave pen in Alexandria
• Grand Review of the Army marching in Washington, D.C., May 1865.

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LC-B813

3,028 original wet plate negatives and some copy negatives made for the production of cartes de visite, cut from larger plates, primarily 2-1/4 x 3-1/2", 1860s. Some negatives are uncut and contain two portraits.

• Studio portraits of Union and Confederate soldiers, including Gens. G. T. Beauregard, Burnside, Grant, E. A. Hitchcock, Hooker, Robert E. Lee, Sickles, and Sherman.
• Also includes a few group portraits, such as the Sanitary Commission and a group of sailors.

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LC-B814

308 original wet plate negatives made for the production of cartes de visite, three exposures per negatives, 4 x 10," 1860s.

• Primarily studio portraits of Union soldiers, including Generals Belknap, Abner Doubleday, Hunter, and Montgomery C. Meigs.
• The series also includes a few portraits of military wives with their husbands and a man holding a satchel of newspapers.
• Some images show sitters posed in front of various painted backdrops. The Brady studio was not known to use such backdrops. Brady may have purchased these negatives from other studios.

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LC-B815

670 original wet plate stereo negatives in pairs, 4 x 10"; made between 1862-1869. These images will not display in three dimensions unless the left and right halves are transposed. (For information on resources for viewing digitized stereographs in 3-D, see "Viewing Online Stereographs in 3-D," in the "About the Stereographs" section of the online catalog.) Negatives by Alexander Gardner, Timothy O 'Sullivan, and James Gibson. Many of these negatives were listed in Alexander Gardner's 1863 Catalogue of Photographic Incidents of the War. Mainly war views, the negatives document:

• Burnside Bridge, Antietam, Maryland
• contrabands; fortifications at Petersburg, Virginia
• Richmond in ruins
• soldiers in camp, near Yorktown, Virginia
• the Grand Review of the Army, Washington, D.C., 1865

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LC- B817

758 original wet plate negatives, 8 x 10", 1862-1865. Negatives by Timothy O'Sullivan, Alexander Gardner, and others. Includes:

• group portraits of soldiers
• camps and forts, especially Brandy Station and Petersburg, Virginia
• numerous views of military personnel and government buildings in Washington, D.C.
• portraits of the Lincoln conspirators and their execution

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LC-B8155

4 original wet plate glass negatives, approximately 5 x 7", 1860s.
Includes a portrait of General Robert E. Lee by Julian Vannerson and portraits of Maj. Gen. W. S. Harney and Gen. W. H. French.
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LC-B8156

44 original and copy negatives, 4-3/4 x 7-1/2", 1863.
Union soldiers at Folly and Morris islands during the siege of Charleston, South Carolina, photographed by Haas & Peale.
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LC-B8175

3 original glass plate negatives, 8 x 10" or smaller, 1864-1865.
Portraits of Robert E. Lee, Abraham Lincoln, and Ulysses S. Grant.
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LC-BH822

25 original wet plate stereo pair negatives. These stereo negatives are sequenced so that the images can be viewed as three-dimensional ("3-D") images when seen through a viewer. (For information on resources for viewing digitized stereographs in 3-D, see "Viewing Online Stereographs in 3-D," in the "About the Stereographs" section of the online catalog.) Negatives by Samuel A. Cooley and others.
Civil War views:

• Union officer groups
• camp fortifications
• naval operations, etc.

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LC-BH831

168 original wet plate glass negatives, 8 x 10", 1860-1865.
Civil War military and naval officers, with several portraits of General Robert E. Lee. Included in this series are Union generals C. C. Augur, Wm. F. Barry, Samuel S. Carroll, George Custer, Francis Blair and staff, Gordon Granger, Judson Kilpatrick, Ed. McCook, Alfred Pleasonton, Phil Sheridan and staff, and Admiral D. D. Porter.
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LC-BH84

10 wet plate negatives, 8 x 10" or smaller, 1860-1865.
Civil War views in:

• Alexandria and Petersburg, Virginia
• Charleston, South Carolina
• Washington Navy Yard

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Film Copy Negatives and Transparencies Made by the Library of Congress

LC-B8171

8 x 10 film copy negatives made by the Library from low contrast black & white prints from negatives in series B811, B815, and B817.
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LC-B8172

8 x 10 film copy negatives made by the Library from low contrast black & white copy prints made from original negatives in series LC-B813 and LC-B814.
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LC-B8184

8 x 10 film copy negatives made by the Library from prints from various sources.
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LC-USZ61

5 x 7 film copy negatives made by the Library from file prints.
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LC-USZ62

8 x 10 film copy negatives made by the Library from file prints.
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LC-USZC2

2 x 2 color slides made by the Library from file prints.
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LC-USZC4

4 x 5 color film transparencies made by the Library from file prints.
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LC-USZC6

8 x 10 color film transparencies made by the Library from file prints.
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