Black-and-white copy negatives, ranging in size from 4x5- to 8x10-inches, have been made for all of the Library's daguerreotypes. In addition, 4x5-inch color transparencies have been made for some (approximately 116) of the daguerreotypes. The daguerreotype cases have not been systematically photographed. Descriptive information about the cases can be found in the catalog records.
The majority of digital images in the online collection presentation were made from the black-and-white copy negatives in 1996 by contractors and Library of Congress staff. In 1998 images were made by a contractor for most of the 4x5 color transparencies. In 2000-01 a contractor made additional images of the remaining 4x5 color transparencies. The specifications for these digital images are noted below. Additional digital images may be made in the future as new acquisitions are added to the collection.
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black-and-white digital images: 4x5 negative - Reproduction Number begins with "LC-USZ6-" |
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| Uncompressed Archival Images ("u.tif") | |
| File size approximately 1.5mb | |
| Spatial resolution: | About 1,400 pixels on the long side with the short side falling where it may. |
|
Tonal resolution (pixel-depth) - Grayscale: |
8 bits per pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| File size approximately 13mb | |
| Spatial resolution: | About 4,000 pixels on the long side with the short side falling where it may. |
|
Tonal resolution (pixel-depth) - Grayscale: |
8 bits per pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| Compressed Service Images ("r.jpg" and "v.jpg") | |
| Medium spatial resolution ("r.jpg"): | 640 pixels on the long side with the short side falling where it may. |
| Higher spatial resolution ("v.jpg"): | 1,024 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits per pixel |
| File format: | JFIF (JPEG File Interchange Format) |
| Thumbnail Images ("t.gif") | |
| Spatial resolution: | About 150 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits-per-pixel; palettes optimized (adaptive palettes) for each image. |
| Online copy: | GIF (Graphics Interchange Format) format |
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black-and-white digital images: 5x7 negative - Reproduction Number begins with "LC-USZ61-" |
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| Uncompressed Archival Images ("u.tif") | |
| File size approximately 11mb | |
| Spatial resolution: | About 4,000 pixels on the long side with the short side falling where it may. |
|
Tonal resolution (pixel-depth) - Grayscale: |
8 bits per pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| Compressed Service Images ("r.jpg" and "v.jpg") | |
| Medium spatial resolution ("r.jpg"): | 640 pixels on the long side with the short side falling where it may. |
| Higher spatial resolution ("v.jpg"): | 1,024 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits per pixel |
| File format: | JFIF (JPEG File Interchange Format) |
| Thumbnail Images ("t.gif") | |
| Spatial resolution: | About 150 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits-per-pixel; palettes optimized (adaptive palettes) for each image. |
| Online copy: | GIF (Graphics Interchange Format) format |
|
black-and-white digital images: 8x10 negative - Reproduction Number begins with "LC-USZ62-" |
|
| Uncompressed Archival Images ("u.tif") | |
| File size approximately 1.5mb | |
| Spatial resolution: | About 1,400 pixels on the long side with the short side falling where it may. |
|
Tonal resolution (pixel-depth) - Grayscale: |
8 bits per pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| File size approximately 13mb | |
| Spatial resolution: | About 4,000 pixels on the long side with the short side falling where it may. |
|
Tonal resolution (pixel-depth) - Grayscale: |
8 bits per pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| Compressed Service Images ("r.jpg" and "v.jpg") | |
| Medium spatial resolution ("r.jpg"): | 640 pixels on the long side with the short side falling where it may. |
| Higher spatial resolution ("v.jpg"): | 1,024 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits per pixel |
| File format: | JFIF (JPEG File Interchange Format) |
| Thumbnail Images ("t.gif") | |
| Spatial resolution: | About 150 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Grayscale: |
8 bits-per-pixel; palettes optimized (adaptive palettes) for each image. |
| Online copy: | GIF (Graphics Interchange Format) format |
|
color digital images: 4x5 color transparency - Reproduction Number begins with "LC-USZC4-" |
|
| Uncompressed Archival Images ("u.tif") | |
| &File size approximately 5mb | |
| Spatial resolution: | About 1,500 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Color: |
24 bits-per-pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| File size approximately 60mb | |
| Spatial resolution: | About 5,000 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Color: |
24 bits-per-pixel |
| File format: | Tagged Image File Format (TIFF) ver. 6.0 |
| Compressed Service Images ("r.jpg" and "v.jpg") | |
| Medium spatial resolution ("r.jpg"): | 640 pixels on the long side with the short side falling where it may. |
| Higher spatial resolution ("v.jpg"): | 1,024 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Color: |
24 bits-per-pixel |
| File format: | JFIF (JPEG File Interchange Format) |
| Thumbnail Images ("t.gif") | |
| Spatial resolution: | About 150 pixels on the long side with the short side falling where it may. |
|
Tonal (pixel-depth) resolution - Color: |
8 bits-per-pixel; palettes optimized (adaptive palettes) for each image. |
|
File format: Online copy: |
GIF (Graphics Interchange Format) format |