Image capture standards

The following image capture standards are used by the National Library in digitisation of its collection material. All digital master images are saved as uncompressed TIFF files.

Material type Tonal resolution (pixel depth) Spatial resolution*
Colour reflective formats, including:
  • coloured maps
  • pencil sketches with wash
  • sepia or coloured photographic prints
  • printed music
  • manuscripts
  • objects
RGB 8 bit
(24 bits per pixel)

Larger than A4: 300ppi
A5 to A4: 600ppi
A7 to A6: 1200ppi
Under A7: 2000ppi

Colour transparencies, including 35mm RGB 16 bit
(48 bits per pixel)
2000 ppi
Colour negatives, including 35mm RGB 16 bit
(48 bits per pixel)
2000 ppi
Note: two digital masters are created: colour negative and colour positive; derivatives are created from the colour positive.
B&W reflective formats, including:
  • photographic prints
  • black and white line art
  • black and white map
RGB 8 bit
(24 bits per pixel)
Larger than A4: 300ppi
A5 to A4: 600ppi
A7 to A6: 1200ppi
Under A7: 2000ppi
B&W negatives 35mm Greyscale
16 bits per pixel
3000 ppi (TIFF master and derivatives positive)
B&W negatives larger than 35mm Greyscale
16 bits per pixel
2000 ppi (TIFF master and derivatives positive)
B&W microfilm masters of newspapers (for the Australian Newspapers Digitisation Program) Greyscale and bi-tonal (image optimised for OCR) 400 ppi
Print publications RGB 8 bit
(24 bits per pixel)
400 ppi at 100%
Print publications scanned for Copies Direct orders Bi-tonal (or RGB where the copy would be illegible if scanned as bi-tonal image) 400 ppi at 100%
Multi-page TIFF format

NB* The resolution given is based on the optical capabilities of the scanning device, not interpolated resolution.