Infrared Photography

Jonathan Jackson, The International Dunhuang Project
  1. Infrared and IDP
  2. What is Infrared?
  3. Sources of Infrared
  4. Light Control and Filtration
  5. Focus and Exposure
  6. Infrared in Practice
    1. Example 1: IOL Tib J 76 Tibetan booklet cover
    2. Example 2: IOL Tib J 738 Tibetan paper fragment
    3. Example 3: Or.8210/S.3454 Manuscript repairs and recycling
    4. Example 4: Or.8211/1682 Kharoshti 'Propeller' woodslip
    5. Example 5: Or.8210/S.5556 Damaged Chinese booklet
  8. Case Study 1
  9. Case Study 2

Infrared in Practice

The equipment used by IDP for infrared imaging can be found in many institutions where digital imaging of documents is undertaken. At the heart of the system is a PhaseOne Powerphase FX+ digital scanning back. This type of camera back utilises a tri-linear sensor that scans the document in minute sections, building up the image to produce high resolution digital files.

FXPowerphase FXbase FXsensor

The camera backs are mounted on DeVere 480 Vertical copy cameras. The camera is in turn secured to the wall and floor to prevent any movement during exposures.

Lighting is provided by Elinchrom tungsten modelling lights. The lighting needs to be constant with a scanning back and flash, although a preferred choice of light source cannot be used.

Infrared filtering is by 'cutout' or narrow band filters in the range 750nm to 1000nm, which sit over the rear element of the camera lens, within the camera bellows. With the filters mounted inside the camera no unfiltered light can reach the scanning back.

 Infrared Camera
Examples
< 5. Focus and Exposure | 6a. Example 1: IOL Tib J 76 Tibetan booklet cover >