Image Digitization Standards

Staff digitizing images

Master Image

• Tonal depth: 24-bit colour
• Format: TIFF
• Compression: Uncompressed
• Spatial Resolution: 1200 dpi
• Represents as closely as possible the information contained in the original
• Serves as long term source for derivative files
• Can serve as surrogate for the original
• High quality
• Used for creating high quality print reproductions
• Remains in a controlled environment, with limited use

Web Access Image

• Tonal depth: 24-bit colour
• Format: JPEG
• Compression: Compressed for speed of access
• Spatial Resolution:
  • Resize images to 640 pixels in their longest dimension (either width or height)
  • 96 dpi
• Used in place of master image for general web access
• Generally fits within viewing area of average monitor
• Reasonable file size for fast download time; does not require a fast network connection
• Acceptable quality for general research

Thumbnail Image

• Format: JPEG
• Compression: Compressed for speed of access
• Spatial Resolution:
  • Resize originals to 150 pixels in their longest dimension (either width or height)
  • 72 dpi
• Designed to display quickly online; allows users to determine whether they want to view Access Image
• Serves as a long term source for derivative files 

Equipment Used for PreVIEW

• Scannx Book Scanner 6167  [Book Scanner and Document Capture]
• Epson Perfection V750 Pro [Flatbed Scanner]
• Kodak Perfect Page [Document Scanner]
• Plustek Optic Film 120 [Film Scanner – 35mm negatives, mounted slides, & 120mm medium format film]
• Colortrac Smart tlf Gxt T42 [Large Format Map Scanner]
• Digital Asset Management System – Canto Cumulus 8 Web Publisher Pro
• Storage Array Network (SAN): Dell EMC RAID storage System with Fibre
• Channel host interfaces and Fibre Channel disk drives
• Dell Graphic Workstations with 20” LCD Monitor