| *Calculate ppi based on image dimensions excluding mounts and borders - e.g. 6000 pixels long edge desired, divided by 5 inch edge (such as with a 4x5) = 1200 so the scanning resolution should be 1200 ppi | |||||
| PHOTOGRAPHS | RECOMMENDED | ALTERNATIVE MINIMUM | |||
| Transmissive originals (Film, Slides, and Negatives) | Bit-Depth (Color Depth) | Pixel Dimensions / Spatial Resolutions | Pixel Dimensions / Spatial Resolutions | File Formats | Recommended derivative formats |
| 35mm up to 4x5 (smaller than 20 sq in) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | *4000 pixels across long dimension of image area; sized to match original, no magnification or reduction | 3000 pixels across long dimension for all rectangular formats and sizes; 2700 pixels by 2700 pixels for square formats regardless of size; approx. 2100 ppi for 35mm originals and ranging down to the appropriate resolution to produce the desired size file from larger originals, approx. 600 ppi for 4”x5” and 300 ppi for 8”x10” originals; Dimension:File dimensions set to 10” across long dimension at 300 ppi for rectangular formats and to 9”x9” at 300 ppi for square formats | TIFF, JPEG2000 | jpgs, gifs, png or as needed |
| Equal to or larger than 4x5 in. and up to 8x10 in. (equal to or larger than 20 in. square and up to 80 in. square) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | **6000 pixels across long dimension of image area; sized to match original, no magnification or reduction | TIFF, JPEG2000 | jpgs, gifs, png or as needed | |
| Equal to or larger than 8x10 in. (Equal to or larger than 80 in. square) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | ***8000 pixels across long dimension of image area; sized to match original, no magnification or reduction | TIFF, JPEG2000 | jpgs, gifs, png or as needed | |
| *Approximately 2800 ppi for 35 mm originals and ranging down to approximately 800 ppi for originals approaching 4x5 in. | |||||
| **Approximately 1200 ppi for 4x5 in. originals and ranging down to approximately 600 ppi for originals approaching 8x10 in. | |||||
| ***Approximately 800 ppi for originals approximately 8x10 in. and ranging down to the appropriate resolution to produce the desired size file from larger originals. | |||||
| Reflective Originals (Prints) | |||||
| 8x10 or smaller (smaller than or equal to 80 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | *4000 pixels across long dimension of image area, excluding mounts and borders; sized to match original, no magnification or reduction | 3000 pixels across long dimension for all rectangular formats and sizes; 2700 pixels by 2700 pixels for square formats regardless of size; approx. 2100 ppi for 35mm originals and ranging down to the appropriate resolution to produce the desired size file from larger originals, approx. 600 ppi for 4”x5” and 300 ppi for 8”x10” originals; Dimension:File dimensions set to 10” across long dimension at 300 ppi for rectangular formats and to 9”x9” at 300 ppi for square formats | TIFF, JPEG2000 | jpgs, gifs, png or as needed |
| Larger than 8x10 up to 11x14 (80-154 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | **6000 pixels across long dimension of image area, excluding mounts and borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | jpgs, gifs, png or as needed | |
| Larger than 11x14 (Equal to or larger than 154 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | ***8000 pixels across long dimension of image area, excluding mounts and borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | jpgs, gifs, png or as needed | |
| *Approximately 400 ppi for 8x10 in. originals and ranging up to the appropriate resolution to produce the desired size file from smaller originals, approximately 570 ppi for 5x7 in. and 800 ppi for 4x5 in. or 3.5x5 in. originals. | |||||
| **Approximately 600 ppi for originals approximately 8x10 in. and ranging down to approximately 430 ppi for 11x14 in.originals. | |||||
| ***Approximately 570 ppi for originals 11x14 in. and ranging down to the appropriate resolution to produce the desired size file from larger originals. | |||||
| UMD Minimal Requirements for Creating Digital Images | |||||
| Rare/damaged printed text, book illustrations, photographic prints, graphic art, or works of art on paper where the longest side is: | |||||
| less than or equal to 1.5" | 2750-4000 ppi | ||||
| 1.6"-5.5" | 800-1200 ppi | ||||
| 5.6"-11.5" | 400-600 ppi | ||||
| 11.6"-18" | 300 ppi | ||||
| greater than 18" | 300 ppi | This assessment presumes that the oversize item will be used at its original size. If only a portion of the item is to be used, following the guidelines for materials at the size of the portion to be used. | |||
| Aerial - Transmissive originals | |||||
| If scans of aerial photography will be used for oversized reproduction, follow the scanning recommendations for the next largest format (e.g., if your original is 70 mm wide, follow the specifications for 127 mm wide roll film to achieve 8,000 pixels across the long dimensions). | |||||
| 70mm wide & medium format roll film (smaller than 10 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | *6000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | 4000 pixels across long dimension of image area; approx. 1800 ppi for 6cm x 6cm originals and ranging down to the appropriate resolution to produce the desired size file from large originals, approx. 800 ppi for 4”x5” and 400 ppi for 8”x10” originals; Dimension: File dimensions set to 10” across long dimension at 400 ppi for all formats | TIFF, JPEG2000 | |
| 127 mm wide roll film, 4x5 up to 5x7 sheet film (10 up to 35 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | **8000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | ||
| Larger than 127mm wide roll film, and larger than 5x7 sheet film (Larger than 35 square inches) | 8-bit grayscale (BW), 24-bit RGB (color & monochrome) | ***10000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | ||
| *Approximately 2700 ppi for 70 mm originalsand ranging down to the appropriate resolution to produce the desired size file from larger originals. | |||||
| **Approximately 1600 ppi for 4x5 in. originals and ranging down to approximately 1100 ppi for 5x7 in. originals. | |||||
| ***Approximately 2000 ppi for 5x5 in. originals and ranging down to the appropriate resolution to produce the desired size filefrom larger originals. | |||||
| Aerial - Reflective originals | |||||
| smaller than 8x10 (smaller than 80 square inches) | 8-bit grayscale (BW), 24-bit RGB (color) | *4000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | 3000 pixels across long dimension of image area; approx. 300 ppi for 8”x10” originals and ranging up to the appropriate resolution to produce the desired size file from smaller originals, approx. 570 ppi for 5”x7” and 800 ppi for 4”x5” or 3.5”x5” originals | TIFF, JPEG2000 | |
| Aerial - Reflection Scanning (8x10-11x14/80-154 sq in) | 8-bit grayscale (BW), 24-bit RGB (color) | **6000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | ||
| Aerial - Reflection Scanning (>11x14/154 sq in) | 8-bit grayscale (BW), 24-bit RGB (color) | ***8000 pixels across long dimension of image area, excluding borders; sized to match original, no magnification or reduction | TIFF, JPEG2000 | ||
| *Approximately 400 ppi for originals approximately 8x10 in. andranging up to the appropriate resolution to produce the desired size file from smaller originals, approximately 570 ppi for5x7 in. and 800 ppi for 4x5 in. originals. | |||||
| **Approximately 600 ppi for 8x10 in. originals and ranging down to approximately 430 ppi for 11x14 in. originals. | |||||
| ***Approximately 570 ppi for 11x14in. originals and ranging down to the appropriate resolution to produce the desired size file from larger originals. | |||||
| Comments | |||||
| Spatial resolution is measured as pixels per inch or PPI; pixels per millimeter or pixels per centimeter are also used. Resolution is often referred to as dots per inch or DPI. In common usage, the terms PPI and DPI are used interchangeably. Since raster image files are composed of pixels, technically PPI is a more accurate term and is used in this document (one example in support of using the PPI term is that Adobe Photoshop software uses the pixels per inch terminology). DPI is the appropriate term for describing printer resolution (actual dots vs. pixels); however, DPI is used often in scanning and image processing software to refer to spatial resolution and this usage is an understandable convention. | |||||
| http://www.digitizationguidelines.gov/guidelines/digitize-technical.html | |||||