Image File Specifications For Patron Requests

Prepared: 5/20/2013

All image files created by the Digital Imaging Lab at Columbia University Libraries become digital assets to be archived and repurposed as needs arise.

Because of this we strive to create files that adhere to best practices in the Cultural Heritage Imaging field but no larger.  Below are the default file format specifications used for digitizing Columbia University Libraries holdings. If for any reason a patron needs a digital file that surpasses these specifications they should to contact the manager of the Digital Imaging Lab, Dave Ortiz at 212-854-5515


All digital files conform to the TIFF 6.0 specification.

All digital files are captured as RGB files and have the Adobe RGB (1998) color profile embedded.


Bit Depth:

All image files are captured at 48 bits but for delivery purposes are downsized to 24 bits.  This reduces the file size significantly while maintaining the same reproduction size. If for any reason a patron desires the 48-bit version of the file they should request it at the time of placing the order.



As per NARA standards, the Digital Imaging Lab has a sliding scale of resolutions for flat copy work as follows:


Smaller than 8” x 10”                                               600 ppi

8” x 10” – 11” x 14”                                                  400 ppi

Larger than 11’ x 14” up to 18” x 23”                          300 ppi



Upon request at the time of placing the order JPEG files will be generated. It is assumed that the purpose of these derivative files will be for viewing on computer monitors. The file format specifications are:


Resolution: 100 ppi

Pixel Dimensions: 1500 pixels on the longest side

Color Profile: sRGB

Compression: 10 (in Photoshop)