As mentioned in a previous blog post, Andrew and Naomi from Case Western Reserve came to the lab in late February to demo the MISHA portable multispectral imaging system, made possible by a National Endowment for the Humanities (NEH) Research Grant awarded to the Rochester Institute of Technology. In total, Naomi and Andrew imaged five objects from the Public Library, UC Libraries, and one of our third-party institutional clients. Imaged books included, one Otto Ege item, two Book of Hours, one undated Latin music manuscript, and a Pentateuch volume from Hebrew Union College. In all, thirteen separate capture sessions were carried out for the five objects. Afterwards, the raw data from the capture sessions was shared with the Lab via OSF (Open Science Framework) so that I could process the data in the NEH grant supported open access RCHIVE (Rochester Cultural Heritage Image processing and Visualization Environment) software.
The image gallery above shows the recto of leaf 32 from the Public Library’s copy of Fifty Original Leaves from Medieval Manuscripts, Western Europe, XII-XVI century, by Otto Ege.
While each of the capture sessions took only two minutes to complete, I found that processing the raw data took me a bit longer to figure out. Processing the data felt very similar to using CHI’s RTI Builder and Viewer software. However, in this situation I did not have a week-long training opportunity to learn the ins and outs of the software and its functions. For the Spectral Analysis App, I had only a couple of brief documents to refer to, so the learning curve was a little steeper. I also experienced some issues with the software while processing the data with the flatfield files provided from the capture session. But in the end, the processed files seemed fine without the flatfield data, so it all worked out.
The above image gallery depicts a leaf from Hebrew Union College’s Pentateuch Ms. 1 with adhesive staining, tape, and prior repairs.
What I discovered through processing all the MISHA data and then comparing it to the existing specialized imaging done in the Lab was that the suite of imaging we do in the Lab is very well rounded and, in general, suits our needs and our clientele quite well. In many cases, our results were at least comparable, if not better (specifically within the UV wavelengths) than the results accomplished using the MISHA. And, especially with our UV workflow, though our current capture time might be slightly longer than that of MISHA, the data processing time is significantly shorter and, in the case of UV especially, the side-by-side results of the accurate normal illumination next to the full color UV image(s) is ideal for our purposes.
The images above show an example of scraped text on parchment from UC Libraries Hours of the Virgin from 1475, currently in the Lab for treatment. Compare these MISHA generated images to the documentation performed by Catarina Figueirinhas and myself using the Lab’s equipment and processes below.
That said, I am fully aware that not everyone has access to the equipment/training that I have been fortunate to curate/experience over the last five plus years. Also, not everyone uses their finished data exactly how we do. For instance, the needs and expectations of a conservation lab and cultural heritage institutions can be very different. Even within the conservation field, how we use the data provided by specialized imaging in our hybrid book and paper lab is quite different from the kind of data needed by a fine arts conservation lab. Ultimately, I think the core audience for a system like the MISHA system is an organization looking to expand their suite of imaging services, or an institution with no multispectral imaging infrastructure interested in imaging collections in a quick and easy manner. Though for the latter, I would say that there is a big learning curve in manipulating and processing the data, but if greater focus is put into making the software and processing steps user-friendly, especially to novice users, it is completely manageable. And if this step is taken, I think the system could help a lot of institutions dive deeper into the materiality and history of their collections.
The images above depict another example of faded, scraped text. This flyleaf is from an undated Latin music manuscript that is part of the Public Library’s collection. The images below represent imaging done by the Lab, both normal illumination and UV radiation, with the goal to increase the legibility of the inscription.
In the end, multispectral imaging is just plain FUN! So, the idea of making it more accessible to a wider audience is extremely exciting and I think the work that NEH, RIT, and colleagues like Andrew and Naomi are doing to share the power and wonder of multispectral imaging is amazing. The idea of a portable multispectral imaging system with free processing software that does not take a PhD to use is boundary-breaking, and it gives us a glimpse into a future of accessible and exciting imaging, which thus allows us to see and understand more of the past. I will always be an advocate for that kind of imaging!
Jessica Ebert [UCL] – Sr. Conservation & Photographic Documentation Specialist
