Hamilton College Digital Collections

Figure 1: Specifications for Digitizing Three-dimensional Objects

Use

Spatial Resolution

Resolution

Bit
Depth

Color
Space

Editing/
Processing

File Format/Compression

Storage

Archival Master
(AM)

Long-term archive

4,000+ pixels on the LS.1

6+ Megapixels (on digital camera)
(10-15 MP preferred)

24-bit

RGB

Check grayscale and color accuracy

TIFF, with little endian (IBM PC) Byte Order; no compression; with embedded ICC Color Profile

Stored on 2 media: CD, DVD, tape, spinning disk

Working
Master
(WM)

To create derivatives.

Publication printing.

sRGB

-Change file format2

-Saved as sRGB

-Tone & color adjusted

-Sharpened

Same as AM, but may be compressed with LZW compression if saving storage space is essential.3

If kept, same as AM.

Static
Delivery File

Internet delivery for viewing on monitor

600 pix. on LS (no zoom);
600+ pix. on LS (zoom)

150 dpi

-Reduced dimensions
-Sharpened

JPEG, medium quality, 5-7; or high quality, 8-10 (of 10)

Spinning disk and backup tape

[1] - The larger the physical object, the larger the number of pixels on the long side will need to be.

[2] - If you are using Photoshop to edit the Working Master, change the file's TIFF format to PSD, Photoshop's native file format, which allows for more editing functionality.

[3] - To provide zoom and pan functionality for an image, you can upload the Working Master (TIFF) file to a "full resolution" CONTENTdm collection. CONTENTdm will then convert the TIFF format to a JPEG2000 format.

Updated: May 6, 2008, pjm