Standards for Digital Images

Broad policies and standards utilized by Digital Imaging Services photographers.

Reflective Material

See Best Practices for Reflective Material for more detailed information by material type.

Preservation and Service Files

Two distinct files are created for every image captured, a Preservation File and a Service File. The Preservation File is spec’d for long-term retention and use, whereas the Service File is spec’d for ease of access and digital display.

PPI Range by Material Type

General Practices for Reflective Material

• Color accuracy should be measured against an object-level target, not the original object.
• Objects should be photographed recto/verso (front and back), including blank pages.
• Images should be oriented correctly, generally in a top-down readable fashion based on the first page or capture of the object. Subsequent pages should maintain this orientation.
• If a backing sheet is used, it must extend beyond the edge of the page.
• For oversized materials, PPI should be determined by the item’s fine details, overall size, and the amount of captures that may be required to create a composite. A single capture is preferable in most cases provided that the details are legible.

Transmissive Material

See Best Practices for Transmissive Materials for more detailed information.

Preservation and Service Files

Two distinct files are created for every image captured, a Preservation File and a Service File. The Preservation File is spec’d for long-term retention and use, whereas the Service File is spec’d for ease of access and digital display.

Black and White

Color

PPI Range by Material Dimensions

General Practices for Transmissive Material

• Film should typically be photographed with the emulsion side down. The emulsion side is the more matte surface with a raised texture, while the base side is shiny. Any text on the film should read correctly when viewed with the emulsion side down.