The digitisation of the Book of St Albans manuscript by Matthew Paris was quite possibly the most anticipated step within the Medieval manuscript digitisation project currently being conducted within the Library of Trinity College Dublin. This high value manuscript was first photographed as black and white collotype prints for the M.R. James Facsimile edition in 1924 and in the 1980s a selection of images from the manuscript were captured on colour transparency film and scanned. The colour transparency slides show the pastel green hues well. Furthermore, considering a comparison between the resolution of fine grain film and high-resolution digital imaging is still contestable, I do not believe I can immediately say the resolution of the digital surrogate images taken on a medium format digital back camera is well and truly above what can be captured with fine grain film in terms of image resolution. However, the high dynamic range, colour accuracy and ease of use and speed of a medium format digital back camera makes the true hues and gold highlights seen within the miniatures throughout the Book of St Albans manuscript much easier to render correctly.
Digitising a high value manuscript such as the Book of St Albans involves slightly more planning than other medieval manuscripts as multiple people need to be involved throughout the process to ensure the safety and security of the manuscript. My role first off was to calculate how long I anticipated the digitisation to take place and whether there was a possibility to be able to also capture extra images of a selected number of illustrations using raking light to show the texture within the illustrations. Considering multiple expertise needed to be involved throughout the process and the manuscript is permanently stored in high security, I had a limited amount of time to complete all the digitisation. Although, the fact that this manuscript only has 77 folios made the planning slightly easier. Overall, the most difficult part of the digitisation process was creating the correct lighting to accurately show the course gold highlights which are seen within many of the illustrations, whilst not washing out the pastel green colourisation.
Lighting set up for pastel colours and gold
For most of the photography conducted within our Digital Collection studios we use a standard twin lighting set up with one flash head placed on either side of the subject positioned 90 cm above the subject and placed at a 35-degree angle towards the subject plane. The standard lighting set up was used for the lighting set up whilst digitising the Book of St Albans manuscript. In addition, a large silver reflector was placed over the top of the camera and over the top of the two flash heads and directly above the subject plane. The large silver reflector covered the entire diameter of the subject area and lighting circumference. The large reflector was kept in place directly above the subject throughout the entire shoot. Whilst shooting the miniatures with gold illumination an extra light was placed in front of the subject and pointed directly upwards towards the large silver reflector, this light was also set to the lowest setting. The purpose of using the extra light whilst photographing the miniatures with the gold illuminations was to help bring out the gold highlights which are often hard to capture with the standard lighting set up alone. The large reflector was kept in the same position throughout the shoot to avoid image exposure and the white balance changing too much once the extra lighting was temporarily added. The extra light was kept on the lowest setting also for this reason and to avoid flattening the green pastel colourisation seen throughout the manuscript.
The raking light set up
There are some distinct features in the illustrations in the Book of St Albans that are not easily seen by the unaided eye and are not obvious on the collotype facsimile. These hidden features are the modeling of the surface of parts of the uncoloured vellum. This effect can be seen on the folds of draped clothing, the necks, and haunches of the horses (fol. 49r, Figure 3b.3) as well as the brick work of the abbey church (fol. 60r, Figure 3b.4) and on the laths of the boat (fol. 62r). These effects that were created by Matthew Paris can only be seen by casting a raking light across the illustrations. (Wogan-Browne & Fenster, 2010).
From left, raking light image of folio 60r and close-up of the hidden texturing in the brick work, which can only be seen when using raking light.
The idea behind the raking light set up was to show the hidden texture and detailing in the tinted illustrations which have hidden modelling effects that cannot otherwise be seen with standard lighting. When using the raking light set up the raised parts of the parchment and detailing in the illustrations facing the light are illuminated whilst the parts facing away from the light are shadowed. This allows one to see how rough and rigid parts of the illustrations are, which can give researchers a better insight into the techniques used to create parts of the detailing in the illustrations.
At the very end of the shoot where I was using the original lighting set up, I still had a small bit of time with the manuscript to capture a selected number of folios with a raking light set up. Alison Ray, the Archivist/Project Manager on the Carnegie Medieval Manuscript digitisation project created a list of the selected folios with illustrations showing the unique surface modelling, which I referred to. To capture the raking lighting images the manuscript was positioned on the motorised conservation cradle in the exact same way as it was in the previous set up, whilst only one flash head was used with the diffusing soft box removed. The flash head was positioned to one side of the manuscript 15 cm (about 5.91 in) above the surface of the manuscript. The raking light was pointed downwards slightly, for the light to be skimming across the page. To carry out a raking light shoot it is ideally best to have a light set up on either side of the manuscript and take a shot with each light individually. The two shots would then be comparable in what extra detail and texture they show. Unfortunately, we were quite limited in our lighting set-up and extremely limited on time with the manuscript, therefore we did not have the flexibility of using an extra raking light at a different angle. However, in future this would be our raking light set up of choice. In addition to having two flash heads set up on either side of the manuscript with extra time I would like to experiment with capturing raking light images with the flash heads set up at slightly different angles and distances from the subject to determine which set up produces the most ideal results.
By Caroline Harding
Senior Digital Photographer Manuscripts for Medieval Studies Project
The work of the Manuscripts for Medieval Studies project has been supported by a grant from Carnegie Corporation New York.
Virtual Trinity Library is a digitisation initiative of the Library of Trinity College Dublin’s most valued collections. It will conserve, catalogue, curate, digitise and research these unique collections of national importance, making them accessible to a global audience, from schoolchildren to scholars.
Wogan Browne, J., Fenster, T. S., (2010), The Life of St Alban by Matthew Paris, Vol 2.