Digitising Bibles

Eumaeus - The Noble Swineherd: "The two books are a Wycliff Bible, an early English translation dating from approximately AD 1410, and the famous St. Chad’s Gospel,"

"For the work, we will use an old-fashioned bellows camera with a medum-format digital back. The digital sensor is monochromatic, and 38 megapixels. The resolution is a good thing, and the lack of color is also a good thing. In a normal, color, digital camera of, say, 24 megapixels, there is a color filter laid over the sensor. Of the 24 million pixels, 8 will be filtered through red, 8 will be filtered through green, and 8 will be filtered through blue. So each full color "pixel" will consume three pixels of resolution. The software in the camera will merge the three pixels into one, full-color pixel, at the cost of some softness to the image.

Our black-and-white camera has no color filter in front of the sensor. This does not mean that we won’t have lovely color images of these Bibles, however.

The lights for this photography consist of banks of LED lights, with each bank bank of LEDs emitting a specific frequency of light. There are thirteen banks, ranging from ultraviolet, through the visible spectrum (blues, greens, oranges, reds) down to several levels of infrared. The camera and lights are controlled by a computer, which will automatically cycle through the spectra of light, taking a picture for each one.

The result is thirteen monochromatic images, each showing particular features of the page, as different kinds of ink and different kinds of stains or damage reflect differently.

At the end, the thirteen images can be merged to create full-color images that take advantage of the full resolution of the sensor. Other “false color” images can be generated to suit particular kinds of analysis.

In addition to this digital photography, the team is capturing structured light data, which involves projecting a series of patterns on the page, and photographing each one. From this data, we can generate a 3-dimensional model of the page."