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Imaging Standards

The following tables aggregate standards based for digital preservation based on consortial requirements and based on the work of national governance bodies and interest groups.

Printed and handwritten text
Scan Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Black and white print 1-bit 600 Bitonal 1:1 TIFF with Group 4 lossless compression AND PDF/A
Black and white  + illustrations, or handwritten 8-bit 400 Grayscale 1:1 Uncompressed TIFF AND PDF/A
Text with color images, or handwritten 24-bit 400 RGB 1:1 Uncompressed TIFF AND PDF/A

Printed photographs
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Black and white 8-bit 600 Grayscale 1:1 Uncompressed Tiff
Color 24-bit 600 RGB 1:1 Uncompressed TIFF

Large format maps and posters
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Black and white 1-bit 5000 - 10,000 pixels on the longest side Bitonal 1:1 Uncompressed TIFF
Grayscale 8-bit 5000 - 10,000 pixels on the longest side Grayscale 1:1 Uncompressed TIFF
Color 24-bit 5000 - 10,000 pixels on the longest side RGB 1:1 Uncompressed TIFF

Negatives and transparencies
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Black and white 8-bit 5000 pixels on the longest side* Grayscale 1:1 Uncompressed TIFF
Color 24-bit 5000 pixels on the longest side* RGB 1:1 Uncompressed TIFF

*Common film sizes and corresponding resolutions to achieve 5000 pixels on the longest side.

Film Size Scanner Resolution
35 mm 4000 dpi
2x3 in 2400 dpi
6x9 cm 2400 dpi
6x7 cm 2400 dpi
6x6 cm 2400 dpi
7x9 cm 2400 dpi
4x4 cm 4000 dpi
4x5 in 1200 dpi
8x10 in 1200 dpi

Books
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Black and white 1-bit 600 Bitonal 1:1 Uncompressed TIFF
Grayscale 8-bit 400 Grayscale 1:1 Uncompressed Tiff
Color 24-bit 400 RGB 1:1 Uncompressed TIFF

Newspapers
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Original 24-bit 400 RGB 1:1 Uncompressed TIFF

Microfilm
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
16mm 8-bit 400 Grayscale 1:1 Uncompressed TIFF
35mm 8-bit 400 RGB 1:1 Uncompressed TIFF

Microfiche
Type Bit Depth Resolution (ppi/dpi) Color space Scale File format
Microfiche 8-bit 400 Grayscale 1:1 Uncompressed TIFF